Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Synopsis... As the upper-level trough departs the Pacific Northwest on D2/Thursday, thunderstorm activity will diminish. It does appear that some lingering risk for isolated dry thunderstorm activity will continue past 12z into D2/Thursday mainly across portions of central Oregon. As such, an isolated dry thunderstorm area was added with this outlook. Otherwise, fire weather concerns will remain low across the CONUS with generally light winds and building high pressure across the western US. ..Thornton.. 09/03/2025 ...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 0150 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Synopsis... As the upper-level trough departs the Pacific Northwest on D2/Thursday, thunderstorm activity will diminish. It does appear that some lingering risk for isolated dry thunderstorm activity will continue past 12z into D2/Thursday mainly across portions of central Oregon. As such, an isolated dry thunderstorm area was added with this outlook. Otherwise, fire weather concerns will remain low across the CONUS with generally light winds and building high pressure across the western US. ..Thornton.. 09/03/2025 ...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 0150 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Synopsis... As the upper-level trough departs the Pacific Northwest on D2/Thursday, thunderstorm activity will diminish. It does appear that some lingering risk for isolated dry thunderstorm activity will continue past 12z into D2/Thursday mainly across portions of central Oregon. As such, an isolated dry thunderstorm area was added with this outlook. Otherwise, fire weather concerns will remain low across the CONUS with generally light winds and building high pressure across the western US. ..Thornton.. 09/03/2025 ...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 0150 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Synopsis... As the upper-level trough departs the Pacific Northwest on D2/Thursday, thunderstorm activity will diminish. It does appear that some lingering risk for isolated dry thunderstorm activity will continue past 12z into D2/Thursday mainly across portions of central Oregon. As such, an isolated dry thunderstorm area was added with this outlook. Otherwise, fire weather concerns will remain low across the CONUS with generally light winds and building high pressure across the western US. ..Thornton.. 09/03/2025 ...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 0150 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Synopsis... As the upper-level trough departs the Pacific Northwest on D2/Thursday, thunderstorm activity will diminish. It does appear that some lingering risk for isolated dry thunderstorm activity will continue past 12z into D2/Thursday mainly across portions of central Oregon. As such, an isolated dry thunderstorm area was added with this outlook. Otherwise, fire weather concerns will remain low across the CONUS with generally light winds and building high pressure across the western US. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...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 0149 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...Synopsis... A weak upper-level trough will continue to move northward across northern California into the Pacific Northwest on Wednesday. Lift associated with this feature will promote isolated to scattered thunderstorm activity. Thunderstorms will likely be ongoing at the beginning of the period with a second round developing by the afternoon. Overall, a mix of wet/dry thunderstorms is expected across the driest fuels in northern California, far western Nevada, and central Oregon. While locally higher totals will be possible in the strongest storms, ensemble guidance generally shows < 0.10" across much of this region. New lightning starts were reported on Tuesday in these areas, with rainfall amounts 0.10-0.25". An isolated dry thunderstorm area was maintained with this outlook to support this potential. ..Thornton.. 09/03/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1253 AM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN TENNESSEE NORTHWARD INTO NORTHERN NEW YORK... ...SUMMARY... Scattered strong thunderstorms may impact a corridor from east Tennessee northward to the US-Canadian border across northern New York on Thursday, accompanied by a risk for potentially damaging wind gusts. ... Synopsis ... A highly amplified midlevel pattern will continue through Thursday/Day-2 as a large ridge pushes north through western Canada and a downstream trough persists across much of the eastern United States. Within this amplified pattern, a seasonably cold midlevel low will exist across Ontario, with multiple lobes of vorticity rotating around the low. One such vorticity lobe/shortwave trough will move east across the Great Lakes bringing with it increasing ascent across portions of the eastern US. At the surface, a cold front associated with the midlevel shortwave trough will stretch through the Plains east-northeast into the lower Great Lakes at the start of the forecast period. This cold front will make slow progress southward across the Plains and faster progress east across the eastern Great Lakes region. ... East Tennessee northward into Upstate New York ... Seasonable moisture will be in place across the region ahead of the advancing surface cold front. Diurnal heating of this airmass should result in pockets of most-unstable CAPE up to 1500 J/kg to develop by early afternoon across southern portions of the region to perhaps 750 J/kg across northern portions of the area. Thunderstorms, or their remnants, ongoing across portions of eastern Ohio and western Pennsylvania at the start of the period, should weaken/dissipate through the morning as they move east. These showers/storms or their outflow may provide potential foci for thunderstorm development/intensification during the afternoon. To the west, increasing large scale ascent associated with the shortwave trough and low-level convergence along the surface cold front should support additional bands of thunderstorms. The best thermodynamics will reside across Tennessee and adjacent areas, with the best deep-layer shear displaced to the north across northern Pennsylvania and New York. However, the joint distribution of forecast profiles of shear and buoyancy should favor thunderstorm organization into small multicell clusters or small linear segments, with the strongest of these capable of some damaging wind potential. ..Marsh.. 09/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1236 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms with potential for large to very large hail and severe wind gusts are expected this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...Central Plains/Lower Missouri Valley... At mid-levels, heights will fall over much of the central U.S., as a low moves southward toward the western Great Lakes and as a shortwave trough moves through the Upper Midwest. At the surface, a cold front will advance southward across the central Plains and lower Missouri Valley. Ahead of the front, surface dewpoints in the 60s F will contribute to a pocket of moderate instability by afternoon. Warming surface temperatures and increasing low-level convergence near the front will support scattered thunderstorm development along the northern edge of the stronger instability this afternoon. These storms will become organized and move south-southeastward across central and eastern Kansas, and western Missouri during the late afternoon and early to mid evening. RAP forecast soundings near the instability axis across east-central Kansas late this afternoon have MLCAPE peaking in the 2000 to 2500 J/kg range, with steep lapse rates in the low to mid-levels. 0-6 km shear is forecast to be near 45 knots, due to a combination of speed shear and directional shear from the surface to about 600 mb. This environment will support large hail with supercells. Moderate deep-layer shear and mid-level lapse rates near 7.5 C/km will support a potential for hailstones greater than 2 inches in diameter with the more intense updrafts. Isolated severe wind gusts will also be possible with supercells, or with bowing line segments that develop out of merging cells. The severe threat is expected to persist into the mid evening, as several small clusters move southeastward into southeast Kansas and southwest Missouri. ..Broyles/Thornton.. 09/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1236 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms with potential for large to very large hail and severe wind gusts are expected this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...Central Plains/Lower Missouri Valley... At mid-levels, heights will fall over much of the central U.S., as a low moves southward toward the western Great Lakes and as a shortwave trough moves through the Upper Midwest. At the surface, a cold front will advance southward across the central Plains and lower Missouri Valley. Ahead of the front, surface dewpoints in the 60s F will contribute to a pocket of moderate instability by afternoon. Warming surface temperatures and increasing low-level convergence near the front will support scattered thunderstorm development along the northern edge of the stronger instability this afternoon. These storms will become organized and move south-southeastward across central and eastern Kansas, and western Missouri during the late afternoon and early to mid evening. RAP forecast soundings near the instability axis across east-central Kansas late this afternoon have MLCAPE peaking in the 2000 to 2500 J/kg range, with steep lapse rates in the low to mid-levels. 0-6 km shear is forecast to be near 45 knots, due to a combination of speed shear and directional shear from the surface to about 600 mb. This environment will support large hail with supercells. Moderate deep-layer shear and mid-level lapse rates near 7.5 C/km will support a potential for hailstones greater than 2 inches in diameter with the more intense updrafts. Isolated severe wind gusts will also be possible with supercells, or with bowing line segments that develop out of merging cells. The severe threat is expected to persist into the mid evening, as several small clusters move southeastward into southeast Kansas and southwest Missouri. ..Broyles/Thornton.. 09/03/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1236 AM CDT Wed Sep 03 2025 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms with potential for large to very large hail and severe wind gusts are expected this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...Central Plains/Lower Missouri Valley... At mid-levels, heights will fall over much of the central U.S., as a low moves southward toward the western Great Lakes and as a shortwave trough moves through the Upper Midwest. At the surface, a cold front will advance southward across the central Plains and lower Missouri Valley. Ahead of the front, surface dewpoints in the 60s F will contribute to a pocket of moderate instability by afternoon. Warming surface temperatures and increasing low-level convergence near the front will support scattered thunderstorm development along the northern edge of the stronger instability this afternoon. These storms will become organized and move south-southeastward across central and eastern Kansas, and western Missouri during the late afternoon and early to mid evening. RAP forecast soundings near the instability axis across east-central Kansas late this afternoon have MLCAPE peaking in the 2000 to 2500 J/kg range, with steep lapse rates in the low to mid-levels. 0-6 km shear is forecast to be near 45 knots, due to a combination of speed shear and directional shear from the surface to about 600 mb. This environment will support large hail with supercells. Moderate deep-layer shear and mid-level lapse rates near 7.5 C/km will support a potential for hailstones greater than 2 inches in diameter with the more intense updrafts. Isolated severe wind gusts will also be possible with supercells, or with bowing line segments that develop out of merging cells. The severe threat is expected to persist into the mid evening, as several small clusters move southeastward into southeast Kansas and southwest Missouri. ..Broyles/Thornton.. 09/03/2025 Read more