Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not forecast on Monday. ...Synopsis... An upper low will progress eastward into Quebec, with a large area of cyclonic flow aloft over much of the eastern CONUS on Monday. West of this trough, and upper ridge will remain from the Four Corners states into western TX. At the surface, an expansive area of high pressure will result in relatively stable/dry conditions over much of the central and eastern CONUS. The leading cold front and bulk of associated thunderstorm activity will stretch from the western Atlantic into the northern Gulf. Western portions of the front will extend into central TX, where southerly winds will maintain a moist and marginally unstable air mass. Early day activity may exist over KS into OK where southerly 850 mb flow may yield elevated instability atop the surface front. Additional storm development is possible south of any such activity into northwest TX, but poor lapse rates and shear aloft will limit severe potential. Otherwise, scattered afternoon thunderstorms are likely over much of the Intermountain West as areas of midlevel moisture persist. ..Jewell.. 08/23/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not forecast on Monday. ...Synopsis... An upper low will progress eastward into Quebec, with a large area of cyclonic flow aloft over much of the eastern CONUS on Monday. West of this trough, and upper ridge will remain from the Four Corners states into western TX. At the surface, an expansive area of high pressure will result in relatively stable/dry conditions over much of the central and eastern CONUS. The leading cold front and bulk of associated thunderstorm activity will stretch from the western Atlantic into the northern Gulf. Western portions of the front will extend into central TX, where southerly winds will maintain a moist and marginally unstable air mass. Early day activity may exist over KS into OK where southerly 850 mb flow may yield elevated instability atop the surface front. Additional storm development is possible south of any such activity into northwest TX, but poor lapse rates and shear aloft will limit severe potential. Otherwise, scattered afternoon thunderstorms are likely over much of the Intermountain West as areas of midlevel moisture persist. ..Jewell.. 08/23/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Sat Aug 23 2025 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not forecast on Monday. ...Synopsis... An upper low will progress eastward into Quebec, with a large area of cyclonic flow aloft over much of the eastern CONUS on Monday. West of this trough, and upper ridge will remain from the Four Corners states into western TX. At the surface, an expansive area of high pressure will result in relatively stable/dry conditions over much of the central and eastern CONUS. The leading cold front and bulk of associated thunderstorm activity will stretch from the western Atlantic into the northern Gulf. Western portions of the front will extend into central TX, where southerly winds will maintain a moist and marginally unstable air mass. Early day activity may exist over KS into OK where southerly 850 mb flow may yield elevated instability atop the surface front. Additional storm development is possible south of any such activity into northwest TX, but poor lapse rates and shear aloft will limit severe potential. Otherwise, scattered afternoon thunderstorms are likely over much of the Intermountain West as areas of midlevel moisture persist. ..Jewell.. 08/23/2025 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Sat Aug 23 2025 Valid 232000Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE COLORADO/WYOMING FRONT RANGE AND ADJACENT CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms appear possible near the Colorado/Wyoming Front Range and central High Plains this afternoon and evening. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton.. 08/23/2025 .PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Aug 23 2025/ ...Front Range/Central High Plains... A mid/upper-level anticyclone centered over the Southwest and Four Corners regions will move little today, with ridging extending northward across much of the Great Basin and Northwest. Modestly enhanced northwesterly mid-level flow will exist today across the central Rockies and adjacent High Plains. A moist post-frontal airmass will remain in place across these areas, with surface dewpoints generally in the mid to upper 50s. Low cloud cover remains prevalent across the central High Plains late this morning, which should continue to hinder destabilization to some extent. Even so, gradual thunderstorm development should eventually occur over the higher terrain by late afternoon as persistent low-level upslope flow aids parcels in reaching their LFCs. This activity should spread generally south-southeastward through the evening along/near the I-25 corridor, while posing an isolated threat for mainly hail due to a combination of modestly steepened lapse rates aloft, sufficient deep-layer shear, and weak to moderate MLCAPE. Occasional strong/gusty winds may also occur. ...Great Lakes/Midwest... Isolated thunderstorms should develop along a cold front this afternoon as it advances eastward across part of the Great Lakes/Midwest. Warm low/mid-level temperatures in the presence of generally low/mid 60s surface dewpoints should limit buoyancy and updraft strength, likely keeping the overall severe potential low. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z The isolated dry thunderstorm highlights were adjusted to cover initial storms progressing over a deep, dry boundary layer, and receptive fuels. Otherwise, the previous forecast remains on track, with no other changes made. ..Squitieri.. 08/23/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Sat Aug 23 2025/ ...Synopsis... Along the northwestern periphery of an amplified large-scale ridge extending from the Southwest to the Pacific Northwest, monsoonal moisture will continue spreading northward from the Great Basin into northern CA and OR. This will contribute to sufficient buoyancy for diurnally driven thunderstorms during the afternoon into the evening -- likely aided by a convectively augmented/generated midlevel vorticity maximum/MCV emerging from the northern Sierra. A mix of wet/dry thunderstorms are expected, and given receptive fuels across the region, lightning-induced ignitions will be possible away from any heavier precipitation cores that evolve. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN COLORADO AND WESTERN KANSAS... ...SUMMARY... A few storms may reach severe thresholds from eastern Colorado into western Kansas Sunday afternoon and evening with hail or wind potential. General thunderstorms will also be concentrated along a cold front from parts of New York across Pennsylvania and into northern Virginia. ...Synopsis... An upper low will remain over James Bay on Sunday, with an expansive upper trough/area of cyclonic flow from the northern Plains across the Great Lakes and into the Northeast. At the surface, high pressure will spread southeastward across the Plains and Midwest, with a cold front roughly from western NY into KY and AR by late afternoon. This boundary will also extend northwestward across OK and into western KS, where it will decelerate during the day. ...Eastern CO into western KS... A zone of stronger instability with MUCAPE to around 2000 J/kg is forecast in the moist east/northeast surface wind regime. Low pressure will also develop over southeast CO during the afternoon coincident with strong heating and steep low-level lapse rates south of the main front/wind shift. All this will occur beneath 25-30 kt midlevel northwesterlies, which will elongate hodographs. Early elevated storms are likely to be ongoing Sunday morning from southwest NE into western KS within a warm advection regime atop the front. It is questionable whether any of this activity would contain hail after 12Z Sunday. However, a weakening trend is likely during the day. Heating west of this area and extending to the Front Range will lead to destabilization, and initial thunderstorms are likely over the mountains after 20Z. As the more unstable air mass becomes uncapped over the lower plains, a few storms may attain severe levels producing hail, and perhaps locally strong gusts. It is unclear how much coverage will occur especially extending farther east into KS, but conditionally the environment will continue to support at least a low-end severe risk. Farther south into the OK/TX Panhandles, a few southeastward-moving cells may develop as well, but lapse rates aloft will be poor. ...Parts of central NY into PA... A narrow band of around 1000-1500 J/kg MUCAPE is forecast to develop ahead of the cold front, with lift along the front supporting scattered afternoon storms. Modest deep-layer shear around 40 kt and primarily straight-line hodographs should yield mainly cellular storm mode. Given this, a relatively shallow/cool boundary, and weak flow below 700 mb, the overall wind threat appears low. While shear will support cellular mode, relatively poor midlevel lapse rates suggest storms may be capable of only small/sub-severe hail. ..Jewell.. 08/23/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN COLORADO AND WESTERN KANSAS... ...SUMMARY... A few storms may reach severe thresholds from eastern Colorado into western Kansas Sunday afternoon and evening with hail or wind potential. General thunderstorms will also be concentrated along a cold front from parts of New York across Pennsylvania and into northern Virginia. ...Synopsis... An upper low will remain over James Bay on Sunday, with an expansive upper trough/area of cyclonic flow from the northern Plains across the Great Lakes and into the Northeast. At the surface, high pressure will spread southeastward across the Plains and Midwest, with a cold front roughly from western NY into KY and AR by late afternoon. This boundary will also extend northwestward across OK and into western KS, where it will decelerate during the day. ...Eastern CO into western KS... A zone of stronger instability with MUCAPE to around 2000 J/kg is forecast in the moist east/northeast surface wind regime. Low pressure will also develop over southeast CO during the afternoon coincident with strong heating and steep low-level lapse rates south of the main front/wind shift. All this will occur beneath 25-30 kt midlevel northwesterlies, which will elongate hodographs. Early elevated storms are likely to be ongoing Sunday morning from southwest NE into western KS within a warm advection regime atop the front. It is questionable whether any of this activity would contain hail after 12Z Sunday. However, a weakening trend is likely during the day. Heating west of this area and extending to the Front Range will lead to destabilization, and initial thunderstorms are likely over the mountains after 20Z. As the more unstable air mass becomes uncapped over the lower plains, a few storms may attain severe levels producing hail, and perhaps locally strong gusts. It is unclear how much coverage will occur especially extending farther east into KS, but conditionally the environment will continue to support at least a low-end severe risk. Farther south into the OK/TX Panhandles, a few southeastward-moving cells may develop as well, but lapse rates aloft will be poor. ...Parts of central NY into PA... A narrow band of around 1000-1500 J/kg MUCAPE is forecast to develop ahead of the cold front, with lift along the front supporting scattered afternoon storms. Modest deep-layer shear around 40 kt and primarily straight-line hodographs should yield mainly cellular storm mode. Given this, a relatively shallow/cool boundary, and weak flow below 700 mb, the overall wind threat appears low. While shear will support cellular mode, relatively poor midlevel lapse rates suggest storms may be capable of only small/sub-severe hail. ..Jewell.. 08/23/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN COLORADO AND WESTERN KANSAS... ...SUMMARY... A few storms may reach severe thresholds from eastern Colorado into western Kansas Sunday afternoon and evening with hail or wind potential. General thunderstorms will also be concentrated along a cold front from parts of New York across Pennsylvania and into northern Virginia. ...Synopsis... An upper low will remain over James Bay on Sunday, with an expansive upper trough/area of cyclonic flow from the northern Plains across the Great Lakes and into the Northeast. At the surface, high pressure will spread southeastward across the Plains and Midwest, with a cold front roughly from western NY into KY and AR by late afternoon. This boundary will also extend northwestward across OK and into western KS, where it will decelerate during the day. ...Eastern CO into western KS... A zone of stronger instability with MUCAPE to around 2000 J/kg is forecast in the moist east/northeast surface wind regime. Low pressure will also develop over southeast CO during the afternoon coincident with strong heating and steep low-level lapse rates south of the main front/wind shift. All this will occur beneath 25-30 kt midlevel northwesterlies, which will elongate hodographs. Early elevated storms are likely to be ongoing Sunday morning from southwest NE into western KS within a warm advection regime atop the front. It is questionable whether any of this activity would contain hail after 12Z Sunday. However, a weakening trend is likely during the day. Heating west of this area and extending to the Front Range will lead to destabilization, and initial thunderstorms are likely over the mountains after 20Z. As the more unstable air mass becomes uncapped over the lower plains, a few storms may attain severe levels producing hail, and perhaps locally strong gusts. It is unclear how much coverage will occur especially extending farther east into KS, but conditionally the environment will continue to support at least a low-end severe risk. Farther south into the OK/TX Panhandles, a few southeastward-moving cells may develop as well, but lapse rates aloft will be poor. ...Parts of central NY into PA... A narrow band of around 1000-1500 J/kg MUCAPE is forecast to develop ahead of the cold front, with lift along the front supporting scattered afternoon storms. Modest deep-layer shear around 40 kt and primarily straight-line hodographs should yield mainly cellular storm mode. Given this, a relatively shallow/cool boundary, and weak flow below 700 mb, the overall wind threat appears low. While shear will support cellular mode, relatively poor midlevel lapse rates suggest storms may be capable of only small/sub-severe hail. ..Jewell.. 08/23/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Aug 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER EASTERN COLORADO AND WESTERN KANSAS... ...SUMMARY... A few storms may reach severe thresholds from eastern Colorado into western Kansas Sunday afternoon and evening with hail or wind potential. General thunderstorms will also be concentrated along a cold front from parts of New York across Pennsylvania and into northern Virginia. ...Synopsis... An upper low will remain over James Bay on Sunday, with an expansive upper trough/area of cyclonic flow from the northern Plains across the Great Lakes and into the Northeast. At the surface, high pressure will spread southeastward across the Plains and Midwest, with a cold front roughly from western NY into KY and AR by late afternoon. This boundary will also extend northwestward across OK and into western KS, where it will decelerate during the day. ...Eastern CO into western KS... A zone of stronger instability with MUCAPE to around 2000 J/kg is forecast in the moist east/northeast surface wind regime. Low pressure will also develop over southeast CO during the afternoon coincident with strong heating and steep low-level lapse rates south of the main front/wind shift. All this will occur beneath 25-30 kt midlevel northwesterlies, which will elongate hodographs. Early elevated storms are likely to be ongoing Sunday morning from southwest NE into western KS within a warm advection regime atop the front. It is questionable whether any of this activity would contain hail after 12Z Sunday. However, a weakening trend is likely during the day. Heating west of this area and extending to the Front Range will lead to destabilization, and initial thunderstorms are likely over the mountains after 20Z. As the more unstable air mass becomes uncapped over the lower plains, a few storms may attain severe levels producing hail, and perhaps locally strong gusts. It is unclear how much coverage will occur especially extending farther east into KS, but conditionally the environment will continue to support at least a low-end severe risk. Farther south into the OK/TX Panhandles, a few southeastward-moving cells may develop as well, but lapse rates aloft will be poor. ...Parts of central NY into PA... A narrow band of around 1000-1500 J/kg MUCAPE is forecast to develop ahead of the cold front, with lift along the front supporting scattered afternoon storms. Modest deep-layer shear around 40 kt and primarily straight-line hodographs should yield mainly cellular storm mode. Given this, a relatively shallow/cool boundary, and weak flow below 700 mb, the overall wind threat appears low. While shear will support cellular mode, relatively poor midlevel lapse rates suggest storms may be capable of only small/sub-severe hail. ..Jewell.. 08/23/2025 Read more