Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Wed Sep 03 2025 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ...SUMMARY... Scattered thunderstorms capable of producing large to very large hail and severe wind gusts should occur this afternoon and evening across parts of the central Plains and lower Missouri Valley. ...20Z Update... The general thunderstorm forecast was updated based on observational trends. The severe probabilities remain unchanged. See the previous forecast for additional information. ..Wendt.. 09/03/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Sep 03 2025/ ...Central Plains into the Lower Missouri Valley... A mid-level shortwave trough over southern SD/eastern NE will continue to advance quickly southeastward today as a large-scale upper-level low moves from western ON to near Lake Superior through the period. The shortwave trough is forecast to reach the lower MO Valley by late afternoon, with an attendant belt of moderately strong northwesterly mid/high-level flow overspreading the central Plains into the mid MS Valley. At the surface, a cold front will advance southward across parts of the central Plains and lower MO Valley, with generally low to mid 60s surface dewpoints present ahead of the boundary. Diurnal heating of this airmass will contribute to moderate instability (MLCAPE around 1000-2000 J/kg) by mid afternoon across central/eastern KS, with weaker instability forecast with eastward extent into MO. As convective inhibition gradually erodes near the front, scattered thunderstorms will likely develop along its length from central KS into the lower MO Valley during the 20-00Z period. Around 35-55 kt of northwesterly flow in the 500-250 mb layer will yield similar values of effective bulk shear, which will support organized updrafts. A few supercells will probably evolve across central/eastern KS and perhaps into western MO, where the main risk will be large to very large hail given steep lapse rates aloft and favorable shear. Severe wind gusts will also be possible with these supercells, or any small clusters/bowing segments that can develop where low-level lapse rates are steepest (mainly KS into northwest OK and parts of the OK/TX Panhandles). Some severe threat should persist into the evening as multiple small clusters move southward into southern KS and adjacent portions of far northern OK and southwest MO, before they eventually weaken as convective inhibition increases with nocturnal cooling. ...Great Lakes/Midwest... Additional thunderstorms should develop this afternoon along/near the cold front across parts of Lower MI into central IL. Poor lapse rates aloft and limited low-level moisture (reference 12Z soundings from APX and ILX) will likely temper the degree of instability that can develop, even with diurnal heating. While occasional strong/gusty winds appear possible with thunderstorms that spread east-southeastward this afternoon and evening, the overall severe threat should remain fairly limited. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...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 0258 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...Northern California and Oregon... A subtle mid-level wave over western NV will move northward into Oregon through the Day 2 period. This feature will interact with existing mid-level moisture supporting isolated thunderstorms across the higher terrain of northern CA, OR Cascades eastward into the John Day and Blue Mountain areas of eastern OR. A relatively dry sub-cloud layer will limit rainfall bringing potential new lightning ignitions over dry fuels. A few thunderstorms are possible into WA Cascades but better coverage should be concentrated south of the Columbia River Gorge area. ..Williams.. 09/03/2025 .PREV DISCUSSION... /ISSUED 0150 AM CDT Wed Sep 03 2025/ ...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. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more