Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Wed Jul 16 2025 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Great Basin... An upward trend of dewpoints and relative humidity shown from recent surface observations across portions of southern NV and southwestern UT should limit fire weather threat for the area today as monsoon moisture increases from the south. Elevated highlights remain across east-central NV and west-central UT where breezy winds, daytime relative humidity at or below 15 percent and dry fuels align. Otherwise, a broad dry thunderstorm threat was maintained for much of the Great Basin and Upper Colorado River Basin this afternoon. More concentrated high-based thunderstorms with minimal rainfall are expected across the Western Slope and eastern Utah where scattered dry thunderstorm highlights remain. ..Williams.. 07/16/2025 .PREV DISCUSSION... /ISSUED 0141 AM CDT Wed Jul 16 2025/ ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Wed Jul 16 2025 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Great Basin... An upward trend of dewpoints and relative humidity shown from recent surface observations across portions of southern NV and southwestern UT should limit fire weather threat for the area today as monsoon moisture increases from the south. Elevated highlights remain across east-central NV and west-central UT where breezy winds, daytime relative humidity at or below 15 percent and dry fuels align. Otherwise, a broad dry thunderstorm threat was maintained for much of the Great Basin and Upper Colorado River Basin this afternoon. More concentrated high-based thunderstorms with minimal rainfall are expected across the Western Slope and eastern Utah where scattered dry thunderstorm highlights remain. ..Williams.. 07/16/2025 .PREV DISCUSSION... /ISSUED 0141 AM CDT Wed Jul 16 2025/ ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Wed Jul 16 2025 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Great Basin... An upward trend of dewpoints and relative humidity shown from recent surface observations across portions of southern NV and southwestern UT should limit fire weather threat for the area today as monsoon moisture increases from the south. Elevated highlights remain across east-central NV and west-central UT where breezy winds, daytime relative humidity at or below 15 percent and dry fuels align. Otherwise, a broad dry thunderstorm threat was maintained for much of the Great Basin and Upper Colorado River Basin this afternoon. More concentrated high-based thunderstorms with minimal rainfall are expected across the Western Slope and eastern Utah where scattered dry thunderstorm highlights remain. ..Williams.. 07/16/2025 .PREV DISCUSSION... /ISSUED 0141 AM CDT Wed Jul 16 2025/ ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Wed Jul 16 2025 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Great Basin... An upward trend of dewpoints and relative humidity shown from recent surface observations across portions of southern NV and southwestern UT should limit fire weather threat for the area today as monsoon moisture increases from the south. Elevated highlights remain across east-central NV and west-central UT where breezy winds, daytime relative humidity at or below 15 percent and dry fuels align. Otherwise, a broad dry thunderstorm threat was maintained for much of the Great Basin and Upper Colorado River Basin this afternoon. More concentrated high-based thunderstorms with minimal rainfall are expected across the Western Slope and eastern Utah where scattered dry thunderstorm highlights remain. ..Williams.. 07/16/2025 .PREV DISCUSSION... /ISSUED 0141 AM CDT Wed Jul 16 2025/ ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Wed Jul 16 2025 Valid 161700Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Great Basin... An upward trend of dewpoints and relative humidity shown from recent surface observations across portions of southern NV and southwestern UT should limit fire weather threat for the area today as monsoon moisture increases from the south. Elevated highlights remain across east-central NV and west-central UT where breezy winds, daytime relative humidity at or below 15 percent and dry fuels align. Otherwise, a broad dry thunderstorm threat was maintained for much of the Great Basin and Upper Colorado River Basin this afternoon. More concentrated high-based thunderstorms with minimal rainfall are expected across the Western Slope and eastern Utah where scattered dry thunderstorm highlights remain. ..Williams.. 07/16/2025 .PREV DISCUSSION... /ISSUED 0141 AM CDT Wed Jul 16 2025/ ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Wed Jul 16 16:55:01 UTC 2025.

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Jul 16 2025 Valid 161630Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST AND CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms are possible this afternoon and evening over parts of the Midwest and central High Plains. ...Midwest/Great Lakes... Late morning radar/satellite imagery shows an MCV over northeast IA co-located with a 1007-mb surface low. A front is draped from northeast to southwest and is forecast to gradually push eastward during the day. The frontal segment east-northeast of the low will remain quasi-stationary and serve as the northern delimiter of a surface-based warm sector. Continued heating of a moist boundary layer will contribute to 1000-2500 J/kg of MLCAPE across central WI into northern/central IL. The modestly enhanced low/mid-level winds associated with the MCV will yield 30-40 kt of effective shear---supporting rotation with a few of the stronger updrafts this afternoon. Semi-discrete thunderstorms developing in a north-south band will likely continue to intensify as ascent overspreads the warm sector over WI and far northern IL. A few supercells are possible with an attendant risk for all hazards. With time late this afternoon and evening, gradual upscale growth into a bowing cluster should occur, with a greater risk for severe/damaging winds towards Lake Michigan and parts of southern Lower MI. ...Central High Plains to Northern Missouri... Indications late this morning are that a convectively reinforced surface front will become stationary across KS into eastern CO with moist, upslope flow into the central High Plains north of the boundary. The southern periphery of stronger mid-level westerly flow will glance the central High Plains where strongly veering flow will result in deep-layer shear supporting storm organization. Although heating will be partially thwarted by persistent low-level cloud cover through at least the early afternoon, sufficient heating is expected to result in scattered to widespread thunderstorms eventually developing during the late afternoon. A few supercells are possible with an accompanying threat for large hail and localized severe gusts. As storm coverage increases, upscale growth into an organized cluster is probable during the evening. Severe gusts will likely become the primary hazard during the evening as the mode becomes more linear and outflow dominant. Farther east across KS into northern MO, isolated convection may develop through peak afternoon heating along the front. While deep-layer shear is forecast to remain fairly modest, strong instability and steep mid-level lapse rates could still support occasional severe hail/wind with the more robust cores that can be sustained. Additional convection may develop along/north of the front this evening in a low-level warm advection regime, while also posing an isolated severe threat. ...Ohio Valley/Mid-Atlantic... A couple of MCVs will focus scattered strong to locally severe thunderstorms mainly this afternoon and early evening. Relatively weak lapse rates and modest deep-layer shear will tend to limit storm organization. Nonetheless, sporadic and isolated bouts of strong to damaging gusts are possible with the stronger thunderstorms through early evening. ...Central Gulf Coast... Modest strengthening of the low-level wind field is expected as a weak tropical disturbance migrates westward over the northern Gulf of America. However, model guidance shows hodographs generally remaining diminutive in size, implying disorganized storm modes (mainly outflow dominant structures in the form of bands and small clusters). ..Smith/Lyons.. 07/16/2025 Read more