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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE GREAT BASIN INTO THE CENTRAL ROCKIES... Much of the forecast remains on track, with only minor changes made to ongoing highlights to reflect the latest guidance consensus. ..Squitieri.. 08/06/2025 .PREV DISCUSSION... /ISSUED 0155 AM CDT Wed Aug 06 2025/ ...Synopsis... A robust midlevel trough will advance eastward across the northwestern CONUS, while an expansive large-scale ridge remains in place across the southern Rockies and adjacent Plains. ...Great Basin into the Central Rockies... Compared to Day 1/Wednesday, slightly stronger deep-layer west-southwesterly flow will overspread the Great Basin into the central Rockies -- between the robust midlevel trough and expansive large-scale ridge. Diurnal heating amid a dry antecedent air mass will yield deep boundary-layer mixing into the strengthening flow aloft, resulting in 5-10 percent RH and 20-25 mph sustained west-southwesterly surface winds (with higher gusts). These hot, dry, and windy conditions atop receptive fuels will lead to another critical fire-weather day across the region. ...Dry Thunderstorms - Southwest into the Central Rockies... Midlevel moisture beneath the expansive large-scale ridge will once again contribute to inverted-V soundings and sufficient instability for diurnally driven high-based thunderstorms. Around 0.5 to 0.70 inch PW will favor dry thunderstorms, and given receptive fuels, lightning-induced ignitions will be a continued concern (along with strong/erratic outflow winds). ...Please see www.spc.noaa.gov/fire for graphic product... Read more

660
ABPZ20 KNHC 061738
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Aug 6 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Henriette, located well east of the Hawaiian Islands.
Henriette is expected to move into the Central Pacific basin
Thursday night.

South of Southern Mexico (EP91):
Microwave satellite imagery and derived surface wind data indicate
that the disturbance located a few hundred miles southwest of the
Gulf of Tehuantepec has become better organized this morning. If
current trends continue, advisories will likely be initiated for
either a tropical depression or tropical storm this afternoon. The
system is forecast to continue moving generally west-northwestward
at 15 to 20 mph, parallel to, but offshore of the coast of Mexico.
Regardless of the system's formation or exact track, heavy rainfall
is possible along the southern coast of Mexico today and tomorrow.
For additional information, including storm warnings, please see
High Seas Forecasts issued by the National Weather Service.
* Formation chance through 48 hours...high...near 100 percent.
* Formation chance through 7 days...high...near 100 percent.

&&
High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFEPI, WMO header FZPN02
KWBC, and on the web at ocean.weather.gov/shtml/NFDHSFEPI.php

$$
Forecaster D. Zelinsky/Santos

000
ABPZ20 KNHC 061738
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Aug 6 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Henriette, located well east of the Hawaiian Islands.
Henriette is expected to move into the Central Pacific basin
Thursday night.

South of Southern Mexico (EP91):
Microwave satellite imagery and derived surface wind data indicate
that the disturbance located a few hundred miles southwest of the
Gulf of Tehuantepec has become better organized this morning. If
current trends continue, advisories will likely be initiated for
either a tropical depression or tropical storm this afternoon. The
system is forecast to continue moving generally west-northwestward
at 15 to 20 mph, parallel to, but offshore of the coast of Mexico.
Regardless of the system's formation or exact track, heavy rainfall
is possible along the southern coast of Mexico today and tomorrow.
For additional information, including storm warnings, please see
High Seas Forecasts issued by the National Weather Service.
* Formation chance through 48 hours...high...near 100 percent.
* Formation chance through 7 days...high...near 100 percent.

&&
High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFEPI, WMO header FZPN02
KWBC, and on the web at ocean.weather.gov/shtml/NFDHSFEPI.php

$$
Forecaster D. Zelinsky/Santos

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Wed Aug 06 2025 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN ND... ...SUMMARY... Scattered severe thunderstorms are expected from mid-afternoon into the night on Thursday. The most likely corridor is centered on North Dakota where a few tornadoes, very large hail, and significant severe gusts are possible. ...Northern Great Plains... Potential for intense supercells growing upscale into a severe MCS appears increasingly likely across ND, with a swath of scattered supercells possible across eastern MT. A shortwave trough will amplify across the Northwest and northern Rockies with a seasonably vigorous impulse rotating through the base. Downstream mid/upper ridging will shift east from the Dakotas to MN, coincident with expansion of a stout EML characterized by very steep lapse rates. This will overspread increasing boundary-layer moisture from evapotranspiration across the Corn Belt, and yield large to extreme buoyancy from southern ND to the Mid-MO Valley by late afternoon Thursday. A strengthening baroclinic zone along the northwest periphery of the MLCAPE plume should aid in increasing thunderstorm development towards mid-afternoon across western ND. Supercells capable of very large hail and a few tornadoes are possible. The initially zonal and moderate mid/upper flow regime will favor upscale growth. Numerous 12Z CAMs support this scenario with indications of a severe MCS spreading eastward, mainly across ND during the evening before gradually waning overnight in MN. Uncertainty does exist on how far south the MCS may build into SD and how far east the damaging wind threat will be maintained in MN amid nocturnally increasing MLCIN. Scattered thunderstorms will also develop across the higher terrain of southwest/south-central MT by late afternoon to early evening. Initial storms should generally pose a marginal severe threat until they impinge on the western periphery of the eastern MT buoyancy plume in the evening. Deep-layer shear profiles should support mainly discrete supercells with some clustering possible late. A mix of both scattered large hail and severe gusts are possible. The eastern extent of the threat overnight into western ND and far northwest SD should be modulated by the earlier round of supercells/MCS. ...IL to western Upper MI... Nebulous, low-probability severe wind/hail potential is evident along the northeast lobe of the expansive buoyancy plume over the central states on Thursday into Thursday night. Most guidance indicates potential for a minor MCV or two from remnants of late D1 convection, ahead of a mid-level ridge over the Dakotas to MN. These may focus mesoscale corridors of diurnal storm development from IL to western Upper MI, but latitudinal uncertainty is large. In addition, modest low-level warm theta-e advection northeast of the Lower MO Valley to IA jet could support a corridor or two of regenerative convection Thursday night. Amid moderate mid-level northwesterlies, sporadic strong storms are anticipated with a few severe storms possible. ..Grams.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 06 2025 Valid 061630Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS TO THE MID-MISSISSIPPI VALLEY. AND PART OF NORTHERN MINNESOTA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across parts of the northern/central Plains to the Mid-Mississippi Valley, and over part of northern Minnesota this afternoon and tonight. ...Northern/Central Plains into the Mid MS Valley... Water-vapor imagery late this morning shows a quasi-zonal flow regime from the northern Intermountain region east into the central Great Plains. A disturbance along the ND/Canadian border will continue east into the western ON vicinity late tonight. Weak mid-level height rises are forecast over the northern Great Plains downstream of a trough moving east into the northwestern CONUS from the eastern Pacific. A belt of stronger mid-level flow (i.e. around 40 kt at 500 mb) will extend across the region, and diurnal heating of the moist airmass in place will foster moderate to strong buoyancy. Forecast soundings show a vigorous combination of shear/buoyancy but nebulous forcing mechanisms suggest storm coverage later today/tonight will likely remain isolated/sparse. Little in the way of large-scale forcing for ascent will contribute to suppressing convective development through at least mid afternoon. Considerable uncertainty in storm development is apparent in convection-allowing models and some of these models show isolated storms perhaps favoring the greater Black Hills area. Will maintain a Marginal risk (level 1 of 5) despite favorable environmental conditions for supercells. Later tonight in association with low-level warm-air advection, a cluster or two of storms may evolve from the eastern half of SD/NE into the lower MO Valley/mid MS Valley. An isolated hail/wind threat could accompany this activity. ...Northern MN... A few storms may develop along the southern periphery of the Canadian Prairies shortwave upper trough and surface low. Lapse rates will be weaker across this area and the favorable thermodynamic environment will be narrow. Any stronger storms will likely remain close to the international border, but could produce locally strong gusts or marginal hail. ..Smith/Wendt.. 08/06/2025 Read more