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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Mon Aug 25 2025 Valid 252000Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN ARIZONA... ...SUMMARY... Isolated severe wind gusts are possible over parts of south-central Arizona this afternoon through early evening. Otherwise, the potential for severe storms is low across the remainder of the continental U.S. ...20z Update... Scattered storms are currently developing over parts of southern AZ and MX ahead of a weak MCV. Additional development is expected the remainder of the afternoon into this evening. Limited buoyancy (MLCAPE ~1000 J/kg) will support multicell updrafts atop fairly dry low-levels. A few of the semi-organized storm clusters could support stronger downdrafts with damaging gust potential. Minor changes were made to the edges of MRGL risk area, see MCD #2014 for short-term information. Elsewhere, scattered storms are expected over the central and western CONUS today/tonight. Limited buoyancy and vertical shear will keep the severe risk low. See the previous discussion. ..Lyons.. 08/25/2025 .PREV DISCUSSION... /ISSUED 1131 AM CDT Mon Aug 25 2025/ ...Synopsis... A large upper trough will remain over the eastern CONUS today, as several embedded shortwave troughs progress within its southern periphery. Extensive upper ridging that currently extends from the southern Plains into the northern Intermountain West is forecast to remain largely in place. Some dampening may occur along the northwestern periphery of this ridging as a slow-moving vorticity maximum continues northeastward from the CO/OR/NV border vicinity into more of eastern OR. Ample monsoonal moisture exists beneath this ridging, contributing to scattered to numerous thunderstorms from the southern/central Rockies westward across the Southwest and much of the Great Basin. Limited vertical shear and weak buoyancy will mitigate the severe potential across the majority of the region. The only exceptions are across central Rockies and immediate foothills, and portions of southern AZ. ...Southern AZ... Ample monsoonal moisture is in place across the region, evidenced by PW values of 1.66 and 1.83 inches from the Phoenix and Yuma 12Z soundings, respectively. Filtered diurnal heating within this moist airmass will support modest buoyancy and afternoon thunderstorm development. A belt of stronger mid-level southeasterly flow (20-25 kt) is forecast to overspread the region this afternoon, providing ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally west-northwestward through the evening. ...Central Rockies... Thunderstorm development is expected across the high terrain by the early afternoon. Poor lapse rates and cooler temperatures will keep buoyancy will be modest, likely limiting overall updraft strength and tempering the severe potential. Even so, moderate northwesterly flow aloft will support long hodographs and the potential for some storm organization if updrafts can become sufficiently deep. An instance or two of hail is possible with any stronger, more long-lived storms. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Mon Aug 25 2025 Valid 252000Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN ARIZONA... ...SUMMARY... Isolated severe wind gusts are possible over parts of south-central Arizona this afternoon through early evening. Otherwise, the potential for severe storms is low across the remainder of the continental U.S. ...20z Update... Scattered storms are currently developing over parts of southern AZ and MX ahead of a weak MCV. Additional development is expected the remainder of the afternoon into this evening. Limited buoyancy (MLCAPE ~1000 J/kg) will support multicell updrafts atop fairly dry low-levels. A few of the semi-organized storm clusters could support stronger downdrafts with damaging gust potential. Minor changes were made to the edges of MRGL risk area, see MCD #2014 for short-term information. Elsewhere, scattered storms are expected over the central and western CONUS today/tonight. Limited buoyancy and vertical shear will keep the severe risk low. See the previous discussion. ..Lyons.. 08/25/2025 .PREV DISCUSSION... /ISSUED 1131 AM CDT Mon Aug 25 2025/ ...Synopsis... A large upper trough will remain over the eastern CONUS today, as several embedded shortwave troughs progress within its southern periphery. Extensive upper ridging that currently extends from the southern Plains into the northern Intermountain West is forecast to remain largely in place. Some dampening may occur along the northwestern periphery of this ridging as a slow-moving vorticity maximum continues northeastward from the CO/OR/NV border vicinity into more of eastern OR. Ample monsoonal moisture exists beneath this ridging, contributing to scattered to numerous thunderstorms from the southern/central Rockies westward across the Southwest and much of the Great Basin. Limited vertical shear and weak buoyancy will mitigate the severe potential across the majority of the region. The only exceptions are across central Rockies and immediate foothills, and portions of southern AZ. ...Southern AZ... Ample monsoonal moisture is in place across the region, evidenced by PW values of 1.66 and 1.83 inches from the Phoenix and Yuma 12Z soundings, respectively. Filtered diurnal heating within this moist airmass will support modest buoyancy and afternoon thunderstorm development. A belt of stronger mid-level southeasterly flow (20-25 kt) is forecast to overspread the region this afternoon, providing ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally west-northwestward through the evening. ...Central Rockies... Thunderstorm development is expected across the high terrain by the early afternoon. Poor lapse rates and cooler temperatures will keep buoyancy will be modest, likely limiting overall updraft strength and tempering the severe potential. Even so, moderate northwesterly flow aloft will support long hodographs and the potential for some storm organization if updrafts can become sufficiently deep. An instance or two of hail is possible with any stronger, more long-lived storms. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Mon Aug 25 2025 Valid 252000Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN ARIZONA... ...SUMMARY... Isolated severe wind gusts are possible over parts of south-central Arizona this afternoon through early evening. Otherwise, the potential for severe storms is low across the remainder of the continental U.S. ...20z Update... Scattered storms are currently developing over parts of southern AZ and MX ahead of a weak MCV. Additional development is expected the remainder of the afternoon into this evening. Limited buoyancy (MLCAPE ~1000 J/kg) will support multicell updrafts atop fairly dry low-levels. A few of the semi-organized storm clusters could support stronger downdrafts with damaging gust potential. Minor changes were made to the edges of MRGL risk area, see MCD #2014 for short-term information. Elsewhere, scattered storms are expected over the central and western CONUS today/tonight. Limited buoyancy and vertical shear will keep the severe risk low. See the previous discussion. ..Lyons.. 08/25/2025 .PREV DISCUSSION... /ISSUED 1131 AM CDT Mon Aug 25 2025/ ...Synopsis... A large upper trough will remain over the eastern CONUS today, as several embedded shortwave troughs progress within its southern periphery. Extensive upper ridging that currently extends from the southern Plains into the northern Intermountain West is forecast to remain largely in place. Some dampening may occur along the northwestern periphery of this ridging as a slow-moving vorticity maximum continues northeastward from the CO/OR/NV border vicinity into more of eastern OR. Ample monsoonal moisture exists beneath this ridging, contributing to scattered to numerous thunderstorms from the southern/central Rockies westward across the Southwest and much of the Great Basin. Limited vertical shear and weak buoyancy will mitigate the severe potential across the majority of the region. The only exceptions are across central Rockies and immediate foothills, and portions of southern AZ. ...Southern AZ... Ample monsoonal moisture is in place across the region, evidenced by PW values of 1.66 and 1.83 inches from the Phoenix and Yuma 12Z soundings, respectively. Filtered diurnal heating within this moist airmass will support modest buoyancy and afternoon thunderstorm development. A belt of stronger mid-level southeasterly flow (20-25 kt) is forecast to overspread the region this afternoon, providing ample shear for some multicell storm clusters. Initial storms which are expected to form across the higher terrain in southeast Arizona may result in congealing outflow with a damaging wind threat as storms move generally west-northwestward through the evening. ...Central Rockies... Thunderstorm development is expected across the high terrain by the early afternoon. Poor lapse rates and cooler temperatures will keep buoyancy will be modest, likely limiting overall updraft strength and tempering the severe potential. Even so, moderate northwesterly flow aloft will support long hodographs and the potential for some storm organization if updrafts can become sufficiently deep. An instance or two of hail is possible with any stronger, more long-lived storms. Read more

MD 2014 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN ARIZONA
Mesoscale Discussion 2014 NWS Storm Prediction Center Norman OK 0237 PM CDT Mon Aug 25 2025 Areas affected...Southern Arizona Concerning...Severe potential...Watch unlikely Valid 251937Z - 252130Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms developing across southeast Arizona may pose a severe wind risk through the late afternoon and early evening hours as they spread west/northwest. Watch issuance is not expected given the localized nature of the threat. DISCUSSION...GOES visible imagery shows a steady increase in coverage and depth of a cumulus field over the higher terrain of southeastern AZ. Recent LightningCast output shows modest, but increasing, probability for lightning flashes across the region and a few flashes have already been noted with one deeper convective tower. Glancing ascent associated with an upstream MCV over the northern Gulf of California, combined with continued daytime heating, should aid in additional thunderstorm development within the next 1-2 hours. Southeasterly mid-level flow will steer isolated to scattered convective cells northwestward into lower elevations. Modest northwesterly low-level winds across south-central AZ will support some degree of hodograph elongation and promote some potential for storm organization and longevity. While small hail is possible, the predominant hazard will be strong to severe gusts given steep low-level lapse rates between 8-9 C/km. Based on the convective environment and recent CAM guidance, sporadic gusts upwards of 50-70 mph appear possible with the stronger downbursts; however, this threat should remain fairly localized given an overall modest kinematic environment. ..Moore/Mosier.. 08/25/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TWC...PSR... LAT...LON 31671233 31921251 32791262 33261255 33571218 33641147 33531100 33351063 33051026 32671000 32100981 31770971 31480969 31270981 31271108 31671233 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0212 PM CDT Mon Aug 25 2025 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The potential for severe storms appears to be low across the continental U.S. on Wednesday. A few stronger storms cannot be ruled out over parts of Minnesota and Wisconsin late in the day, and over eastern Colorado. ...Synopsis and Discussion... An upper trough will exit the Mid Atlantic/Northeast on Wednesday with a secondary wave developing later in the period into the Upper and Middle MS Valley and Great Lakes. Behind the initial trough, high pressure will already be in place over the OH Valley, which will limit destabilization ahead of the secondary system. However, a narrow plume of low-level moisture with 50s F dewpoints will result in a marginally unstable environment across the upper MS Valley by late afternoon. Cool temperatures aloft and modest deep-layer shear of 20-30 kt may result in a few cells capable of mainly small/non-severe hail. Southwest of this region, east/southeast surface winds will persist over the central plains, as a weak surface trough develops over eastern CO. The moist easterly flow toward the Front Range may result in a few stronger cells, perhaps with hail potential. Lapse rates aloft will not be very steep beneath the weak upper ridge, nor will shear be very favorable. However, at least small hail may occur locally during the late afternoon for a short time near peak heating. ..Jewell.. 08/25/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...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 0152 PM CDT Mon Aug 25 2025 Valid 261200Z - 271200Z The IsoDryT area was modified based on the latest high-resolution forecast guidance. There is a low probability that isolated high-based thunderstorms move into the Coast Ranges of northwest Oregon and western Washington, but high-based showers with perhaps sporadic lightning is more likely. Additionally, the Idaho Panhandle into western Montana along the northern boundary of the Day 2 thunder line will have cloud cover, and the dominant mode of convection is likely to be isolated to scattered high-based showers with potentially sporadic lightning intermixed. Deep pyroconvection remains possible on very active large wildfires near the IsoDryT area and along/near what remains of the thermal trough stretching southward into California. ..Nauslar.. 08/25/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Mon Aug 25 2025/ ...Synopsis... Well-established monsoonal moisture will remain in place across the Northwest on Tuesday. Boundary-layer mixing beneath the rich midlevel moisture will contribute to sufficient buoyancy for diurnally driven high-based thunderstorms along the Cascades, where fuels are dry. Inverted-V profiles and 0.80-0.90 inch PW will favor a mix of wet/dry thunderstorms capable of producing gusty/erratic outflow winds and lightning-induced ignitions. A continuation of wet/dry thunderstorms are also expected across parts of northern CA and the northern Rockies, though uncertainty regarding fuel receptiveness in these areas precludes highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

A burn ban was in effect for Lewis County due to dry conditions. Campfires and all open burning were prohibited. WSAZ-TV NBC 3 (Huntington, W.V.), Aug 25, 2025

370
ABPZ20 KNHC 251748
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Mon Aug 25 2025

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Juliette, located in the east Pacific basin several hundred
miles south-southwest of the southern tip of the Baja California
peninsula.

Well Southeast of the Hawaiian Islands:
A trough of low pressure located well southeast of the Hawaiian
Islands is producing disorganized showers and thunderstorms.
Gradual development of this system is possible through the week
while it moves westward at 10 to 15 mph across the central Pacific
basin.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...20 percent.

Well Southwest of the Baja California Peninsula:
A tropical wave located southwest of the Gulf of Tehuantepec is
producing limited shower activity. Some slow development is
possible late this week into the weekend as the system moves
westward to west-northwestward across the central part of the
eastern Pacific basin at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

&&

Public Advisories on Juliette are issued under WMO header WTPZ35
KNHC and under AWIPS header MIATCPEP5. Forecast/Advisories on
Juliette are issued under WMO header WTPZ25 KNHC and under AWIPS
header MIATCMEP5.

$$
Forecaster Berg