Severe Storms

No watches are valid as of Tue Aug 26 23:33:02 UTC 2025.

No Mesoscale Discussions are in effect as of Tue Aug 26 23:33:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0421 PM CDT Tue Aug 26 2025 Valid 281200Z - 031200Z Weak upper lows will drift north out of the northwestern US Day 3/Thursday - Day 4/Friday with remnants of monsoonal moisture surge lingering across portions of Washington and Montana. Drier air will filter in behind this surge as upper-level ridging begins to build slowly over the Intermountain West. Thunderstorm coverage decreases across the Sierra and western Great Basin and northern Rockies Day 4/Friday through the weekend. Another upper low will approach the Northwest coast Day 4/Friday and is likely to move into Washington over the weekend. The track of this upper low remains uncertain, especially from late Day 6/Sunday and beyond. ...Day 3/Thursday - Day 4/Friday... Isolated mixed wet/dry thunderstorms are possible in portions northern Washington into northwest Montana on Day 3/Thursday, with chances potentially lingering in the Idaho Panhandle/northwest Montana on Day 4/Friday. However, there is too much uncertainty regarding actual lightning production and not just high-based showers to introduce probabilities at this time. ...Day 4/Friday - Day 6/Sunday... Dry/breezy conditions are likely in portions of northern California into the Inland Northwest and northwest Great Basin as the upper low approaches and eventually moves into the Northwest. Given the recent lightning and dry fuels, holdovers will be a concern, and any ongoing active large wildfires in these areas are likely to see increased growth. Showers are likely in portions of western Washington associated with the upper low. ..Nauslar.. 08/26/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Aug 26 2025 Valid 262000Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely across the contiguous United States through tonight. ...20Z Update... Isolated strong storms remain possible in the Four Corners vicinity this afternoon. Observed 18Z soundings from Tucson and Flagstaff indicate relatively poor mid-level lapse rates and marginal effective shear. Areas of stronger surface heating could promote stronger outflow winds, but organized severe storms are still unlikely. Only minor modifications were made to the general thunder area based on current observations. Additional forecast details are in the previous discussion below. ..Wendt.. 08/26/2025 .PREV DISCUSSION... /ISSUED 1120 AM CDT Tue Aug 26 2025/ ...Synopsis and Discussion... Large-scale upper troughing will remain over the eastern CONUS today, with surface high pressure dominating much of the central/eastern CONUS. Isolated thunderstorms may occur this afternoon and evening along/south of a surface cold front across parts of the FL Peninsula and central/south TX. However, weak flow aloft and related deep-layer shear should preclude an organized severe threat across these regions with this activity. Scattered to numerous thunderstorms are expected to develop today across much of the interior western CONUS, as upper ridging weakens over the Southwest and multiple weak mid-level perturbations move north-northeastward across the Sierras and Great Basin. Ongoing thunderstorms this morning across the Central Valley in CA will be in a relatively more favorable thermodynamic environment, with modestly steepened mid-level lapse rates compared to locations farther east over the Great Basin potentially supporting small hail with the stronger cores. Still, shear is expected to remain modest at best with westward extent, which should limit updraft organization and overall severe potential. Isolated strong/gusty winds may also occur with any convection that can develop over parts of interior southern CA into the lower CO River Valley, particularly where steepened low-level lapse rates can develop with daytime heating/mixing of the boundary layer away from ongoing cloud cover. The potential for a more concentrated corridor of severe winds still appears low across this area, as it will be in a generally subsident regime behind a weak mid-level shortwave trough advancing northward from southern NV across the Great Basin this afternoon. Finally, an occasional/very isolated strong to severe gust cannot be ruled out across the Four Corners region this afternoon, as convection develops along the Mogollon Rim in northern AZ and subsequently spreads north-northeastward in tandem with a weak mid-level shortwave trough. Even so, deep-layer shear appears too marginal to include low severe wind probabilities with this update. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Tue Aug 26 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the southern Plains Thursday afternoon and evening. ...Southern Plains... An MCS is likely to be ongoing Thursday morning across portions of KS/OK/AR. This activity will likely diminish as it develops southeast toward the ArkLaTex during the afternoon. A composite outflow/surface cold front will then spread south/southwest across OK/the Panhandles/eastern NM by mid-afternoon, though forecast guidance varies on the exact location of the surface boundary. Near the boundary, a corridor of 60s F dewpoints will be in place. While midlevel lapse rates are expected to be relatively weak, rich boundary layer moisture should support a corridor of 1000-2000 J/kg MLCAPE in the vicinity of the Red River. Low-level winds are expected to remain light, but vertically veering profiles will support around 20-30 kt effective shear magnitude. Where strong heating can occur ahead of the boundary, isolated strong storms could develop during the afternoon/evening. Locally strong gusts are possible with this activity. At this time, uncertainty in the evolution of the surface boundary and coverage of thunderstorms precludes severe probabilities. ..Leitman.. 08/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Tue Aug 26 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the southern Plains Thursday afternoon and evening. ...Southern Plains... An MCS is likely to be ongoing Thursday morning across portions of KS/OK/AR. This activity will likely diminish as it develops southeast toward the ArkLaTex during the afternoon. A composite outflow/surface cold front will then spread south/southwest across OK/the Panhandles/eastern NM by mid-afternoon, though forecast guidance varies on the exact location of the surface boundary. Near the boundary, a corridor of 60s F dewpoints will be in place. While midlevel lapse rates are expected to be relatively weak, rich boundary layer moisture should support a corridor of 1000-2000 J/kg MLCAPE in the vicinity of the Red River. Low-level winds are expected to remain light, but vertically veering profiles will support around 20-30 kt effective shear magnitude. Where strong heating can occur ahead of the boundary, isolated strong storms could develop during the afternoon/evening. Locally strong gusts are possible with this activity. At this time, uncertainty in the evolution of the surface boundary and coverage of thunderstorms precludes severe probabilities. ..Leitman.. 08/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Tue Aug 26 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the southern Plains Thursday afternoon and evening. ...Southern Plains... An MCS is likely to be ongoing Thursday morning across portions of KS/OK/AR. This activity will likely diminish as it develops southeast toward the ArkLaTex during the afternoon. A composite outflow/surface cold front will then spread south/southwest across OK/the Panhandles/eastern NM by mid-afternoon, though forecast guidance varies on the exact location of the surface boundary. Near the boundary, a corridor of 60s F dewpoints will be in place. While midlevel lapse rates are expected to be relatively weak, rich boundary layer moisture should support a corridor of 1000-2000 J/kg MLCAPE in the vicinity of the Red River. Low-level winds are expected to remain light, but vertically veering profiles will support around 20-30 kt effective shear magnitude. Where strong heating can occur ahead of the boundary, isolated strong storms could develop during the afternoon/evening. Locally strong gusts are possible with this activity. At this time, uncertainty in the evolution of the surface boundary and coverage of thunderstorms precludes severe probabilities. ..Leitman.. 08/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Tue Aug 26 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the southern Plains Thursday afternoon and evening. ...Southern Plains... An MCS is likely to be ongoing Thursday morning across portions of KS/OK/AR. This activity will likely diminish as it develops southeast toward the ArkLaTex during the afternoon. A composite outflow/surface cold front will then spread south/southwest across OK/the Panhandles/eastern NM by mid-afternoon, though forecast guidance varies on the exact location of the surface boundary. Near the boundary, a corridor of 60s F dewpoints will be in place. While midlevel lapse rates are expected to be relatively weak, rich boundary layer moisture should support a corridor of 1000-2000 J/kg MLCAPE in the vicinity of the Red River. Low-level winds are expected to remain light, but vertically veering profiles will support around 20-30 kt effective shear magnitude. Where strong heating can occur ahead of the boundary, isolated strong storms could develop during the afternoon/evening. Locally strong gusts are possible with this activity. At this time, uncertainty in the evolution of the surface boundary and coverage of thunderstorms precludes severe probabilities. ..Leitman.. 08/26/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Tue Aug 26 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the southern Plains Thursday afternoon and evening. ...Southern Plains... An MCS is likely to be ongoing Thursday morning across portions of KS/OK/AR. This activity will likely diminish as it develops southeast toward the ArkLaTex during the afternoon. A composite outflow/surface cold front will then spread south/southwest across OK/the Panhandles/eastern NM by mid-afternoon, though forecast guidance varies on the exact location of the surface boundary. Near the boundary, a corridor of 60s F dewpoints will be in place. While midlevel lapse rates are expected to be relatively weak, rich boundary layer moisture should support a corridor of 1000-2000 J/kg MLCAPE in the vicinity of the Red River. Low-level winds are expected to remain light, but vertically veering profiles will support around 20-30 kt effective shear magnitude. Where strong heating can occur ahead of the boundary, isolated strong storms could develop during the afternoon/evening. Locally strong gusts are possible with this activity. At this time, uncertainty in the evolution of the surface boundary and coverage of thunderstorms precludes severe probabilities. ..Leitman.. 08/26/2025 Read more