Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sat Jul 19 2025 Valid 192000Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE MIDWEST...AND PARTS OF VIRGINIA INTO NORTH CAROLINA... ...SUMMARY... Scattered strong storms with a severe wind/hail threat are likely this evening across the northern High Plains into the Midwest, with a couple of tornadoes possible over western Nebraska. A few damaging gusts also remain possible with storms over Virginia into North Carolina. ...20Z Update... Substantial changes have been made to the 20Z Day 1 Convective Outlook update. First, Slight risk probabilities have been dropped across portions of the Great Lakes into the OH Valley region. Storms ongoing over this part of the CONUS have not shown robust severe potential thus far. Ongoing storms are also overturning the troposphere during peak heating, casting doubts on adequate airmass modification/destabilization for a renewed organized severe threat. Nonetheless, an isolated damaging gust or brief tornado could occur with a stronger storm that can become sustained, hence the maintenance of a Category 1/Marginal Risk. Wind-driven Slight risk probabilities have been added over portions of the MO River Valley, joining the Slight risk across the High Plains and Midwest areas. From eastern NE into northern IL, thunderstorms are expected to develop along the warm-frontal low-level boundary this evening given enhanced convergence driven by a low-level jet. Furthermore, there is some concern that supercells could congeal into an MCS across central NE and potentially propagate eastward along this boundary early tonight, fostering a damaging gust threat. Otherwise, ongoing multicells over VA into NC will continue through the afternoon with a damaging gust threat. Supercells and small bowing segments are also still expected across the central/northern High Plains this afternoon and evening, accompanied by severe wind and hail. A couple of tornadoes may accompany any more robust, sustained supercells over western into central NE with the onset of low-level jet development this evening. ..Squitieri.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jul 19 2025/ ...Midwest/Great Lakes... An ongoing sub-severe MCS continues east-southeast across IL with an attendant warm advection cluster of thunderstorms downstream over the lower Wabash Valley. Considerable convective overturning coupled with convective cloud debris have acted to limit destabilization thus far across IL into western IN and northward into the southwest Great Lakes. Have reduced severe probabilities this outlook update for northern IL into WI due to limited destabilization, and models converging on limited storm coverage through the remainder of the day and their depiction of primary thunderstorm activity tonight occurring farther south/southwest over IA into central IL towards daybreak. However, downstream of the ongoing thunderstorm clusters over IL/IN, gradual heating will probably support some intensification of storms into the afternoon. Isolated to perhaps scattered damaging winds in small clusters appear to be the primary severe hazard. Other thunderstorm development is possible over Lower MI where a wind-damage threat may materialize with the stronger storms that develop this afternoon. Later this afternoon but more likely into tonight, additional storms are forecast to develop on the trailing outflow with an attendant risk for mainly hail/wind. ...Virginia/North Carolina... A west-east draped frontal zone resides over southern PA to the north of this region. However, a very moist low-level airmass featuring lower to mid 70s dewpoints will continue to heat/destabilize through mid-late afternoon and promote the development of moderate buoyancy. Despite weak mid-level lapse rates, high PW (around 2 inches) will promote water-loaded downdrafts capable of strong to severe gusts and scattered wind damage with the more organized cluster(s). Around 15-25 kt of mid-level westerly flow will favor eastward-moving storm activity. The severe risk is expected to concentrate during the 20-01 UTC period as storms move towards central VA and into eastern VA by this evening. ...Northern/Central Plains... Water-vapor imagery shows a mid-level impulse moving eastward across the northwest quarter of MT this morning. This will continue eastward towards eastern MT and the western Dakotas by early evening. Weaker mid-level westerly flow will remain farther south into the central High Plains. At the surface, a lee trough will extend southward from eastern MT to eastern CO. Generally low to mid 60s surface dewpoints should exist this afternoon along/east of the lee trough, with upper 60s to lower 70s F dewpoints present near a remnant front/boundary in NE. Scattered thunderstorms will likely develop initially over the higher terrain of the northern/central Rockies this afternoon, with additional development farther east along the lee trough. As this convection spreads eastward into a moderately to strongly unstable airmass across the northern/central High Plains, it should strengthen. Weak low-level winds are forecast to veer and increase with height through mid/upper levels, supporting strong deep-layer shear and the potential for supercells. Scattered large hail will be possible with any supercells that can persist, with most guidance indicating a greater concentration of severe thunderstorms across eastern MT into western ND, and separately across western/central NE. Given the presence of steep mid-level lapse rates and 40-50+ kt of deep-layer shear, isolated very large hail appears possible. Recent model guidance indicates a few supercells may develop across west-central NE late this afternoon into the evening. Some enlargement of the hodograph during the evening combined with moist low levels may support a couple hour window for a locally higher tornado risk compared to within this broader region. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Jul 19 2025 Valid 201200Z - 211200Z The primary change with this forecast update was to expand the Elevated fire weather area farther east into portions of eastern/central Wyoming, where the latest high-resolution ensemble guidance suggests several hours of dry and gusty westerly winds during the afternoon/evening. Locally critical fire weather conditions are most likely across the Snake River Plain in Idaho, along the Nevada/Idaho border, and across the Wyoming basin, where sustained surface winds near 25 mph are possible. Continued dry and breezy conditions across the northern Great Basin may also lead to the emergence of lightning holdovers from several recent days of wet/dry thunderstorms - especially along the periphery of heavier thunderstorm cores. Locally elevated fire weather conditions are also possible farther south across portions of central/southern Nevada. At this time, it appears mid-level cloud cover (central Nevada) and recent heavier rainfall (southern Nevada) should limit widespread concerns in these areas. Please see the previous discussion below for more information on tomorrow's fire weather forecast. ..Elliott.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1240 AM CDT Sat Jul 19 2025/ ...Synopsis... The upper-level pattern on Sunday will be similar to Saturday. However, stronger mid-level flow may nudge southward as the upper trough amplifies through the period in the Northwest. Surface troughing will develop in the northern High Plains. ...Northern Great Basin... Another day of elevated fire weather can be expected. With the stronger mid-level winds extending more to the south, greater spatial coverage of at least briefly 20+ mph winds may occur. Overall, however, 15-20 mph winds will be most common. RH of 10-20% will be possible in Nevada while Idaho will more likely see 15-20% by the afternoon. Model guidance does show some potential for high cloud cover which could also limit the duration of critical conditions. Ensemble guidance shows low probability of sustained critical conditions likely on account of those uncertainties. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Jul 19 2025 Valid 201200Z - 211200Z The primary change with this forecast update was to expand the Elevated fire weather area farther east into portions of eastern/central Wyoming, where the latest high-resolution ensemble guidance suggests several hours of dry and gusty westerly winds during the afternoon/evening. Locally critical fire weather conditions are most likely across the Snake River Plain in Idaho, along the Nevada/Idaho border, and across the Wyoming basin, where sustained surface winds near 25 mph are possible. Continued dry and breezy conditions across the northern Great Basin may also lead to the emergence of lightning holdovers from several recent days of wet/dry thunderstorms - especially along the periphery of heavier thunderstorm cores. Locally elevated fire weather conditions are also possible farther south across portions of central/southern Nevada. At this time, it appears mid-level cloud cover (central Nevada) and recent heavier rainfall (southern Nevada) should limit widespread concerns in these areas. Please see the previous discussion below for more information on tomorrow's fire weather forecast. ..Elliott.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1240 AM CDT Sat Jul 19 2025/ ...Synopsis... The upper-level pattern on Sunday will be similar to Saturday. However, stronger mid-level flow may nudge southward as the upper trough amplifies through the period in the Northwest. Surface troughing will develop in the northern High Plains. ...Northern Great Basin... Another day of elevated fire weather can be expected. With the stronger mid-level winds extending more to the south, greater spatial coverage of at least briefly 20+ mph winds may occur. Overall, however, 15-20 mph winds will be most common. RH of 10-20% will be possible in Nevada while Idaho will more likely see 15-20% by the afternoon. Model guidance does show some potential for high cloud cover which could also limit the duration of critical conditions. Ensemble guidance shows low probability of sustained critical conditions likely on account of those uncertainties. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Jul 19 2025 Valid 201200Z - 211200Z The primary change with this forecast update was to expand the Elevated fire weather area farther east into portions of eastern/central Wyoming, where the latest high-resolution ensemble guidance suggests several hours of dry and gusty westerly winds during the afternoon/evening. Locally critical fire weather conditions are most likely across the Snake River Plain in Idaho, along the Nevada/Idaho border, and across the Wyoming basin, where sustained surface winds near 25 mph are possible. Continued dry and breezy conditions across the northern Great Basin may also lead to the emergence of lightning holdovers from several recent days of wet/dry thunderstorms - especially along the periphery of heavier thunderstorm cores. Locally elevated fire weather conditions are also possible farther south across portions of central/southern Nevada. At this time, it appears mid-level cloud cover (central Nevada) and recent heavier rainfall (southern Nevada) should limit widespread concerns in these areas. Please see the previous discussion below for more information on tomorrow's fire weather forecast. ..Elliott.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1240 AM CDT Sat Jul 19 2025/ ...Synopsis... The upper-level pattern on Sunday will be similar to Saturday. However, stronger mid-level flow may nudge southward as the upper trough amplifies through the period in the Northwest. Surface troughing will develop in the northern High Plains. ...Northern Great Basin... Another day of elevated fire weather can be expected. With the stronger mid-level winds extending more to the south, greater spatial coverage of at least briefly 20+ mph winds may occur. Overall, however, 15-20 mph winds will be most common. RH of 10-20% will be possible in Nevada while Idaho will more likely see 15-20% by the afternoon. Model guidance does show some potential for high cloud cover which could also limit the duration of critical conditions. Ensemble guidance shows low probability of sustained critical conditions likely on account of those uncertainties. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Jul 19 2025 Valid 201200Z - 211200Z The primary change with this forecast update was to expand the Elevated fire weather area farther east into portions of eastern/central Wyoming, where the latest high-resolution ensemble guidance suggests several hours of dry and gusty westerly winds during the afternoon/evening. Locally critical fire weather conditions are most likely across the Snake River Plain in Idaho, along the Nevada/Idaho border, and across the Wyoming basin, where sustained surface winds near 25 mph are possible. Continued dry and breezy conditions across the northern Great Basin may also lead to the emergence of lightning holdovers from several recent days of wet/dry thunderstorms - especially along the periphery of heavier thunderstorm cores. Locally elevated fire weather conditions are also possible farther south across portions of central/southern Nevada. At this time, it appears mid-level cloud cover (central Nevada) and recent heavier rainfall (southern Nevada) should limit widespread concerns in these areas. Please see the previous discussion below for more information on tomorrow's fire weather forecast. ..Elliott.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1240 AM CDT Sat Jul 19 2025/ ...Synopsis... The upper-level pattern on Sunday will be similar to Saturday. However, stronger mid-level flow may nudge southward as the upper trough amplifies through the period in the Northwest. Surface troughing will develop in the northern High Plains. ...Northern Great Basin... Another day of elevated fire weather can be expected. With the stronger mid-level winds extending more to the south, greater spatial coverage of at least briefly 20+ mph winds may occur. Overall, however, 15-20 mph winds will be most common. RH of 10-20% will be possible in Nevada while Idaho will more likely see 15-20% by the afternoon. Model guidance does show some potential for high cloud cover which could also limit the duration of critical conditions. Ensemble guidance shows low probability of sustained critical conditions likely on account of those uncertainties. ...Please see www.spc.noaa.gov/fire for graphic product... Read more