Aggregator

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1133 AM CDT Sat Jul 19 2025 Valid 191700Z - 201200Z Today's fire weather forecast remains largely on-track with only minor changes needed based on the latest ensemble forecast guidance. Primary change with this forecast update was to expand the elevated area across the northern Great Basin a bit farther south into portions of central Nevada, where several hours of dry and breezy conditions are expected. The dry/breezy conditions may also lead to the emergence of lightning holdovers across portions of the northern Great Basin, where a combination of wet/dry thunderstorms have occurred over the last week. Lightning data over the past 24-72 hours suggests holdover potential is greatest across portions of central/northeast Nevada into southeast Idaho. Relatively stronger sustained surface winds (near 25 mph) across the Snake River Plain in Idaho will promote locally critical conditions, especially along the periphery of heavier storm cores from the past few days (several heavier cores had 0.5+ inch rainfall), and also in areas devoid of recent rainfall. Please see the previous discussion below for more information on today's fire weather forecast. ..Elliott.. 07/19/2025 .PREV DISCUSSION... /ISSUED 1238 AM CDT Sat Jul 19 2025/ ...Synopsis... Upper-level ridging will persist across much of the southern half of the U.S. today. A weak upper-level low will be positioned over southern California into northern Baja. A belt of stronger mid-level winds will exist across the northern tier states with a low-amplitude shortwave trough moving through the Northwest. A surface trough will deepen in the lee of the northern Rockies. ...Columbia Basin into the northern Great Basin... Offshore high pressure and the deepening trough to the east will promote modestly strong westerly winds across the Cascades. Winds in the Columbia Basin will reach 15-20 mph with perhaps higher speeds within some of the Cascade gaps. RH of 15-20% is possible by the afternoon. In the northern Great Basin, surface winds of 15-20 mph are possible with RH falling into the 10-20% range. Stronger winds are possible in the Snake River Plain as mid-level winds will be stronger and better aligned with the terrain. There, up to 25 mph winds will be possible for a short duration. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Jul 19 2025 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible, along with a potential tornado threat, across the northern/central Plains during the late afternoon and evening. ...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. ..Smith/Weinman.. 07/19/2025 Read more

WW 0525 Status Updates
STATUS REPORT ON WW 525 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SW DSM TO 20 ENE OTM TO 30 N DBQ. ..MOORE..07/19/25 ATTN...WFO...DVN...DMX... STATUS REPORT FOR WS 525 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC031-057-087-101-103-105-115-117-135-139-179-183-191440- IA . IOWA COUNTIES INCLUDED ARE CEDAR DES MOINES HENRY JEFFERSON JOHNSON JONES LOUISA LUCAS MONROE MUSCATINE WAPELLO WASHINGTON THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 525 SEVERE TSTM IA 191005Z - 191500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 525 NWS Storm Prediction Center Norman OK 505 AM CDT Sat Jul 19 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Central and Eastern Iowa * Effective this Saturday morning from 505 AM until 1000 AM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...A cluster of thunderstorms should spread east-southeastward this morning while posing a threat for mainly severe/damaging winds. Peak gusts may reach up to 60-70 mph, and a brief tornado or two also appears possible. The severe thunderstorm watch area is approximately along and 65 statute miles north and south of a line from 25 miles north northwest of Des Moines IA to 30 miles east southeast of Cedar Rapids IA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 30035. ...Gleason Read more

MD 1719 CONCERNING SEVERE THUNDERSTORM WATCH 525... FOR SOUTHEAST IOWA...NORTHEAST MISSOURI...AND WESTERN ILLINOIS
Mesoscale Discussion 1719 NWS Storm Prediction Center Norman OK 0713 AM CDT Sat Jul 19 2025 Areas affected...southeast Iowa...northeast Missouri...and western Illinois Concerning...Severe Thunderstorm Watch 525... Valid 191213Z - 191345Z The severe weather threat for Severe Thunderstorm Watch 525 continues. SUMMARY...A damaging wind threat may persist this morning. A downstream watch is possible. DISCUSSION...A mature line of storms which developed earlier across northern Iowa has progressed south with several measured gusts of 40 to 49 knots. Despite these near-severe wind gusts, no measured severe wind gusts or wind damage has been reported thus far. A brief TDS was sampled earlier by the KDMX WSR-88D, but quickly weakened with minimal additional circulations observed. Considerable uncertainty remains on the evolution of ongoing storms as daytime heating begins. A slightly more favorable orientation of the line has developed across east-central Iowa, but a north-south oriented line of storms is advancing ahead of this portion of the line which may limit any more favorable wind damage threat which could materialize. The portion of the line across central Iowa should continue to move south-southeast, but it is unclear whether surface heating can occur quickly enough before increasing CIN weakens this portion of the line. In addition, the low-level jet which supported/helped maintain the MCS has weakened/veered and will likely provide limited support going forward. Therefore, these competing factors will continue to be monitored and a downstream severe thunderstorm watch may be issued if a severe weather threat appears likely south and east of watch 525. ..Bentley/Gleason.. 07/19/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...LSX...DVN...DMX...EAX... LAT...LON 41619385 41759324 41999254 42199221 42329202 42279141 41738970 41558935 41298913 41138907 40968913 40578929 40318946 40138976 39949025 39889119 40109215 40419267 40819340 41619385 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 1718 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WEST-CENTRAL TO EAST-CENTRAL WISCONSIN
Mesoscale Discussion 1718 NWS Storm Prediction Center Norman OK 0653 AM CDT Sat Jul 19 2025 Areas affected...West-central to east-central Wisconsin Concerning...Severe potential...Watch unlikely Valid 191153Z - 191330Z Probability of Watch Issuance...20 percent SUMMARY...An isolated supercell produced large hail and severe wind this morning. Additional development is possible. DISCUSSION...A very strong supercell developed across Marathon county this morning and produced hail up to 1.5 inches and several reports of wind damage. This supercell developed and persisted along the far northern periphery of weak elevated instability with strong mid-upper-level flow (70-80 knots at 6-8km per area VWPs). Recent radar trends suggest this supercell may weaken before it reaches the Green Bay area. However, additional development is beginning farther west across west-central Wisconsin. It is unclear whether this activity will develop into one or more strong supercells, similar to the lead supercell. However, instability is greater across west-central Wisconsin than the environment which supported the earlier supercell with similarly strong shear. Therefore, it is at least a possibility that one or more additional supercells could develop with a large hail/wind threat. The uncertainty and relatively isolated nature of the threat precludes the need for a watch at this time. However, if several supercells develop and start to move east (a low but non-zero probability), a watch could be necessary. ..Bentley/Gleason.. 07/19/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...DLH...ARX...MPX... LAT...LON 44308787 44398843 44558964 45099253 45569272 45689224 45849137 45649046 45208887 44908799 44678762 44448769 44308787 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Jul 19 2025 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible across the northern/central Plains during the late afternoon and evening. ...Midwest/Great Lakes... A small thunderstorm cluster ongoing this morning across southern/eastern IA should continue to track east-southeastward along an instability gradient across parts of northern MO, IL, and perhaps IN into at least the early afternoon. With sufficient organization and evidence of a cold pool, this cluster may pose a threat for strong to locally damaging winds. Reference Mesoscale Discussion 1719 for more details. The potential for additional strong to severe thunderstorms across the Midwest and Great Lakes regions remains somewhat unclear given rather nebulous/weak forcing aloft. Stronger westerly mid-level flow associated with upper troughing over eastern Canada should tend to remain mostly displaced to the north of the surface warm sector. Still, daytime heating of a moist low-level airmass will likely encourage the development of moderate to locally strong instability by early to mid afternoon away from convective influences. Somewhat stronger flow aloft and related deep-layer shear should be present this afternoon across Lower MI. A mix of multicells and marginal supercells may spread eastward from ongoing activity across WI, or develop separately over this area while posing a threat for isolated severe hail and damaging winds. Farther south into the Midwest/OH Valley, weaker deep-layer shear and the bulk of convection-allowing model guidance suggests that multicell clusters should be the main convective mode. One or more of these clusters will probably persist from the ongoing activity this morning, or develop this afternoon along its outflow. Scattered severe/damaging winds will likely be the main threat as these thunderstorms move east-southeastward this afternoon into early evening across much of the OH Valley/Midwest. This convection should eventually weaken this evening as it encounters a less unstable airmass across the Lower Great Lakes and central Appalachians. ...Virginia/North Carolina... The Mid-Atlantic region will once again reside between upper troughing to the north over the Northeast/eastern Canada, and a mid/upper-level anticyclone anchored over the Southeast. The primary synoptic front remains draped generally east-west along/near the MD/PA/DE border. A very moist low-level airmass remains in place to the south of this boundary, with surface dewpoints generally in the low to mid 70s. A similar convective scenario to yesterday is forecast again today. Diurnal heating of this moist airmass will likely encourage moderate to locally strong MLCAPE by early afternoon, even though mid-level lapse rates are expected to remain poor. Around 15-25 kt of mid-level westerly flow should enable thunderstorms that initially develop over the Appalachians/Blue Ridge to advance eastward towards the lower elevations/coastal regions of VA/NC this afternoon and early evening. Scattered damaging winds should be the main threat with loosely organized multicells/clusters. Isolated hail may occur with the stronger cores as well. ...Northern/Central Plains... An upper trough/low is expected to persist today over western Canada. On the southern periphery of this feature, a weak mid-level shortwave trough should move eastward across the northern Rockies/High Plains through this 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 greater low-level moisture present near a remnant front/boundary in NE. Isolated thunderstorms across northeast MT may pose an isolated hail threat this morning. Current expectations are for scattered thunderstorms to 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. If one or more clusters can develop from the initial supercells, then a greater threat for severe gusts would be realized this evening with eastward extent across the northern/central Plains. There is low confidence in this scenario occurring, however. ..Gleason/Bentley.. 07/19/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Jul 19 2025 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible across the northern/central Plains during the late afternoon and evening. ...Midwest/Great Lakes... A small thunderstorm cluster ongoing this morning across southern/eastern IA should continue to track east-southeastward along an instability gradient across parts of northern MO, IL, and perhaps IN into at least the early afternoon. With sufficient organization and evidence of a cold pool, this cluster may pose a threat for strong to locally damaging winds. Reference Mesoscale Discussion 1719 for more details. The potential for additional strong to severe thunderstorms across the Midwest and Great Lakes regions remains somewhat unclear given rather nebulous/weak forcing aloft. Stronger westerly mid-level flow associated with upper troughing over eastern Canada should tend to remain mostly displaced to the north of the surface warm sector. Still, daytime heating of a moist low-level airmass will likely encourage the development of moderate to locally strong instability by early to mid afternoon away from convective influences. Somewhat stronger flow aloft and related deep-layer shear should be present this afternoon across Lower MI. A mix of multicells and marginal supercells may spread eastward from ongoing activity across WI, or develop separately over this area while posing a threat for isolated severe hail and damaging winds. Farther south into the Midwest/OH Valley, weaker deep-layer shear and the bulk of convection-allowing model guidance suggests that multicell clusters should be the main convective mode. One or more of these clusters will probably persist from the ongoing activity this morning, or develop this afternoon along its outflow. Scattered severe/damaging winds will likely be the main threat as these thunderstorms move east-southeastward this afternoon into early evening across much of the OH Valley/Midwest. This convection should eventually weaken this evening as it encounters a less unstable airmass across the Lower Great Lakes and central Appalachians. ...Virginia/North Carolina... The Mid-Atlantic region will once again reside between upper troughing to the north over the Northeast/eastern Canada, and a mid/upper-level anticyclone anchored over the Southeast. The primary synoptic front remains draped generally east-west along/near the MD/PA/DE border. A very moist low-level airmass remains in place to the south of this boundary, with surface dewpoints generally in the low to mid 70s. A similar convective scenario to yesterday is forecast again today. Diurnal heating of this moist airmass will likely encourage moderate to locally strong MLCAPE by early afternoon, even though mid-level lapse rates are expected to remain poor. Around 15-25 kt of mid-level westerly flow should enable thunderstorms that initially develop over the Appalachians/Blue Ridge to advance eastward towards the lower elevations/coastal regions of VA/NC this afternoon and early evening. Scattered damaging winds should be the main threat with loosely organized multicells/clusters. Isolated hail may occur with the stronger cores as well. ...Northern/Central Plains... An upper trough/low is expected to persist today over western Canada. On the southern periphery of this feature, a weak mid-level shortwave trough should move eastward across the northern Rockies/High Plains through this 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 greater low-level moisture present near a remnant front/boundary in NE. Isolated thunderstorms across northeast MT may pose an isolated hail threat this morning. Current expectations are for scattered thunderstorms to 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. If one or more clusters can develop from the initial supercells, then a greater threat for severe gusts would be realized this evening with eastward extent across the northern/central Plains. There is low confidence in this scenario occurring, however. ..Gleason/Bentley.. 07/19/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Jul 19 2025 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible across the northern/central Plains during the late afternoon and evening. ...Midwest/Great Lakes... A small thunderstorm cluster ongoing this morning across southern/eastern IA should continue to track east-southeastward along an instability gradient across parts of northern MO, IL, and perhaps IN into at least the early afternoon. With sufficient organization and evidence of a cold pool, this cluster may pose a threat for strong to locally damaging winds. Reference Mesoscale Discussion 1719 for more details. The potential for additional strong to severe thunderstorms across the Midwest and Great Lakes regions remains somewhat unclear given rather nebulous/weak forcing aloft. Stronger westerly mid-level flow associated with upper troughing over eastern Canada should tend to remain mostly displaced to the north of the surface warm sector. Still, daytime heating of a moist low-level airmass will likely encourage the development of moderate to locally strong instability by early to mid afternoon away from convective influences. Somewhat stronger flow aloft and related deep-layer shear should be present this afternoon across Lower MI. A mix of multicells and marginal supercells may spread eastward from ongoing activity across WI, or develop separately over this area while posing a threat for isolated severe hail and damaging winds. Farther south into the Midwest/OH Valley, weaker deep-layer shear and the bulk of convection-allowing model guidance suggests that multicell clusters should be the main convective mode. One or more of these clusters will probably persist from the ongoing activity this morning, or develop this afternoon along its outflow. Scattered severe/damaging winds will likely be the main threat as these thunderstorms move east-southeastward this afternoon into early evening across much of the OH Valley/Midwest. This convection should eventually weaken this evening as it encounters a less unstable airmass across the Lower Great Lakes and central Appalachians. ...Virginia/North Carolina... The Mid-Atlantic region will once again reside between upper troughing to the north over the Northeast/eastern Canada, and a mid/upper-level anticyclone anchored over the Southeast. The primary synoptic front remains draped generally east-west along/near the MD/PA/DE border. A very moist low-level airmass remains in place to the south of this boundary, with surface dewpoints generally in the low to mid 70s. A similar convective scenario to yesterday is forecast again today. Diurnal heating of this moist airmass will likely encourage moderate to locally strong MLCAPE by early afternoon, even though mid-level lapse rates are expected to remain poor. Around 15-25 kt of mid-level westerly flow should enable thunderstorms that initially develop over the Appalachians/Blue Ridge to advance eastward towards the lower elevations/coastal regions of VA/NC this afternoon and early evening. Scattered damaging winds should be the main threat with loosely organized multicells/clusters. Isolated hail may occur with the stronger cores as well. ...Northern/Central Plains... An upper trough/low is expected to persist today over western Canada. On the southern periphery of this feature, a weak mid-level shortwave trough should move eastward across the northern Rockies/High Plains through this 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 greater low-level moisture present near a remnant front/boundary in NE. Isolated thunderstorms across northeast MT may pose an isolated hail threat this morning. Current expectations are for scattered thunderstorms to 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. If one or more clusters can develop from the initial supercells, then a greater threat for severe gusts would be realized this evening with eastward extent across the northern/central Plains. There is low confidence in this scenario occurring, however. ..Gleason/Bentley.. 07/19/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Jul 19 2025 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND VIRGINIA/NORTH CAROLINA... ...SUMMARY... Scattered damaging winds are possible today across parts of the Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to very large hail and severe gusts are possible across the northern/central Plains during the late afternoon and evening. ...Midwest/Great Lakes... A small thunderstorm cluster ongoing this morning across southern/eastern IA should continue to track east-southeastward along an instability gradient across parts of northern MO, IL, and perhaps IN into at least the early afternoon. With sufficient organization and evidence of a cold pool, this cluster may pose a threat for strong to locally damaging winds. Reference Mesoscale Discussion 1719 for more details. The potential for additional strong to severe thunderstorms across the Midwest and Great Lakes regions remains somewhat unclear given rather nebulous/weak forcing aloft. Stronger westerly mid-level flow associated with upper troughing over eastern Canada should tend to remain mostly displaced to the north of the surface warm sector. Still, daytime heating of a moist low-level airmass will likely encourage the development of moderate to locally strong instability by early to mid afternoon away from convective influences. Somewhat stronger flow aloft and related deep-layer shear should be present this afternoon across Lower MI. A mix of multicells and marginal supercells may spread eastward from ongoing activity across WI, or develop separately over this area while posing a threat for isolated severe hail and damaging winds. Farther south into the Midwest/OH Valley, weaker deep-layer shear and the bulk of convection-allowing model guidance suggests that multicell clusters should be the main convective mode. One or more of these clusters will probably persist from the ongoing activity this morning, or develop this afternoon along its outflow. Scattered severe/damaging winds will likely be the main threat as these thunderstorms move east-southeastward this afternoon into early evening across much of the OH Valley/Midwest. This convection should eventually weaken this evening as it encounters a less unstable airmass across the Lower Great Lakes and central Appalachians. ...Virginia/North Carolina... The Mid-Atlantic region will once again reside between upper troughing to the north over the Northeast/eastern Canada, and a mid/upper-level anticyclone anchored over the Southeast. The primary synoptic front remains draped generally east-west along/near the MD/PA/DE border. A very moist low-level airmass remains in place to the south of this boundary, with surface dewpoints generally in the low to mid 70s. A similar convective scenario to yesterday is forecast again today. Diurnal heating of this moist airmass will likely encourage moderate to locally strong MLCAPE by early afternoon, even though mid-level lapse rates are expected to remain poor. Around 15-25 kt of mid-level westerly flow should enable thunderstorms that initially develop over the Appalachians/Blue Ridge to advance eastward towards the lower elevations/coastal regions of VA/NC this afternoon and early evening. Scattered damaging winds should be the main threat with loosely organized multicells/clusters. Isolated hail may occur with the stronger cores as well. ...Northern/Central Plains... An upper trough/low is expected to persist today over western Canada. On the southern periphery of this feature, a weak mid-level shortwave trough should move eastward across the northern Rockies/High Plains through this 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 greater low-level moisture present near a remnant front/boundary in NE. Isolated thunderstorms across northeast MT may pose an isolated hail threat this morning. Current expectations are for scattered thunderstorms to 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. If one or more clusters can develop from the initial supercells, then a greater threat for severe gusts would be realized this evening with eastward extent across the northern/central Plains. There is low confidence in this scenario occurring, however. ..Gleason/Bentley.. 07/19/2025 Read more