Severe Storms

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Wed Jul 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Some severe weather is possible on Day 5/Sunday and Day6/Monday across portions of northern Montana and North Dakota as moderate instability builds into the area with moderate mid-level flow southeast of a trough across western Canada. The evolution and timing of this trough remains uncertain and therefore, no severe weather probabilities will be added at this time. Beyond this timeframe, moderate to strong instability is forecast across much of the central and eastern CONUS for much of the extended forecast period with widespread thunderstorm activity likely. Despite this storm coverage and instability, organized severe weather seems unlikely given mostly weak deep-layer shear/flow. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Wed Jul 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Some severe weather is possible on Day 5/Sunday and Day6/Monday across portions of northern Montana and North Dakota as moderate instability builds into the area with moderate mid-level flow southeast of a trough across western Canada. The evolution and timing of this trough remains uncertain and therefore, no severe weather probabilities will be added at this time. Beyond this timeframe, moderate to strong instability is forecast across much of the central and eastern CONUS for much of the extended forecast period with widespread thunderstorm activity likely. Despite this storm coverage and instability, organized severe weather seems unlikely given mostly weak deep-layer shear/flow. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Wed Jul 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Some severe weather is possible on Day 5/Sunday and Day6/Monday across portions of northern Montana and North Dakota as moderate instability builds into the area with moderate mid-level flow southeast of a trough across western Canada. The evolution and timing of this trough remains uncertain and therefore, no severe weather probabilities will be added at this time. Beyond this timeframe, moderate to strong instability is forecast across much of the central and eastern CONUS for much of the extended forecast period with widespread thunderstorm activity likely. Despite this storm coverage and instability, organized severe weather seems unlikely given mostly weak deep-layer shear/flow. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Wed Jul 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Some severe weather is possible on Day 5/Sunday and Day6/Monday across portions of northern Montana and North Dakota as moderate instability builds into the area with moderate mid-level flow southeast of a trough across western Canada. The evolution and timing of this trough remains uncertain and therefore, no severe weather probabilities will be added at this time. Beyond this timeframe, moderate to strong instability is forecast across much of the central and eastern CONUS for much of the extended forecast period with widespread thunderstorm activity likely. Despite this storm coverage and instability, organized severe weather seems unlikely given mostly weak deep-layer shear/flow. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CDT Wed Jul 02 2025 Valid 051200Z - 101200Z ...DISCUSSION... Some severe weather is possible on Day 5/Sunday and Day6/Monday across portions of northern Montana and North Dakota as moderate instability builds into the area with moderate mid-level flow southeast of a trough across western Canada. The evolution and timing of this trough remains uncertain and therefore, no severe weather probabilities will be added at this time. Beyond this timeframe, moderate to strong instability is forecast across much of the central and eastern CONUS for much of the extended forecast period with widespread thunderstorm activity likely. Despite this storm coverage and instability, organized severe weather seems unlikely given mostly weak deep-layer shear/flow. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Wed Jul 02 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Discussion... A mid-level trough will amplify as it moves through the central Plains and into the Upper Midwest on Friday. As this trough advances east, scattered to widespread thunderstorm activity is anticipated within a moderate to strongly unstable airmass. Shear across the warm sector remains highly uncertain at this time as the exact timing of the strengthening mid-level flow remains unclear. If mid-level flow remains 30 knots or less, storm organization may be somewhat nebulous with a threat for isolated damaging wind gusts. However, if stronger mid-level flow can overspread the warm sector during the afternoon/evening, a more concentrated severe weather threat is possible. Due to these uncertainties, a marginal risk is sufficient at this time, but higher severe weather probabilities may be needed if more favorable warm-sector shear appears likely. A mid-level trough will move from the Great Basin into the Northern Rockies on Friday. Widespread thunderstorm activity is anticipated as this trough shifts northeast. At this time it does not appear instability will be sufficient to substantiate a Marginal Risk, but if greater instability materializes, a Marginal Risk may eventually be needed. ..Bentley.. 07/02/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Wed Jul 02 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Discussion... A mid-level trough will amplify as it moves through the central Plains and into the Upper Midwest on Friday. As this trough advances east, scattered to widespread thunderstorm activity is anticipated within a moderate to strongly unstable airmass. Shear across the warm sector remains highly uncertain at this time as the exact timing of the strengthening mid-level flow remains unclear. If mid-level flow remains 30 knots or less, storm organization may be somewhat nebulous with a threat for isolated damaging wind gusts. However, if stronger mid-level flow can overspread the warm sector during the afternoon/evening, a more concentrated severe weather threat is possible. Due to these uncertainties, a marginal risk is sufficient at this time, but higher severe weather probabilities may be needed if more favorable warm-sector shear appears likely. A mid-level trough will move from the Great Basin into the Northern Rockies on Friday. Widespread thunderstorm activity is anticipated as this trough shifts northeast. At this time it does not appear instability will be sufficient to substantiate a Marginal Risk, but if greater instability materializes, a Marginal Risk may eventually be needed. ..Bentley.. 07/02/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Wed Jul 02 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Discussion... A mid-level trough will amplify as it moves through the central Plains and into the Upper Midwest on Friday. As this trough advances east, scattered to widespread thunderstorm activity is anticipated within a moderate to strongly unstable airmass. Shear across the warm sector remains highly uncertain at this time as the exact timing of the strengthening mid-level flow remains unclear. If mid-level flow remains 30 knots or less, storm organization may be somewhat nebulous with a threat for isolated damaging wind gusts. However, if stronger mid-level flow can overspread the warm sector during the afternoon/evening, a more concentrated severe weather threat is possible. Due to these uncertainties, a marginal risk is sufficient at this time, but higher severe weather probabilities may be needed if more favorable warm-sector shear appears likely. A mid-level trough will move from the Great Basin into the Northern Rockies on Friday. Widespread thunderstorm activity is anticipated as this trough shifts northeast. At this time it does not appear instability will be sufficient to substantiate a Marginal Risk, but if greater instability materializes, a Marginal Risk may eventually be needed. ..Bentley.. 07/02/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Wed Jul 02 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...SUMMARY... Scattered strong to severe thunderstorms are expected across portions of the northern Plains and Upper Midwest on Friday. ...Discussion... A mid-level trough will amplify as it moves through the central Plains and into the Upper Midwest on Friday. As this trough advances east, scattered to widespread thunderstorm activity is anticipated within a moderate to strongly unstable airmass. Shear across the warm sector remains highly uncertain at this time as the exact timing of the strengthening mid-level flow remains unclear. If mid-level flow remains 30 knots or less, storm organization may be somewhat nebulous with a threat for isolated damaging wind gusts. However, if stronger mid-level flow can overspread the warm sector during the afternoon/evening, a more concentrated severe weather threat is possible. Due to these uncertainties, a marginal risk is sufficient at this time, but higher severe weather probabilities may be needed if more favorable warm-sector shear appears likely. A mid-level trough will move from the Great Basin into the Northern Rockies on Friday. Widespread thunderstorm activity is anticipated as this trough shifts northeast. At this time it does not appear instability will be sufficient to substantiate a Marginal Risk, but if greater instability materializes, a Marginal Risk may eventually be needed. ..Bentley.. 07/02/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Wed Jul 02 2025 Valid 031200Z - 041200Z ...Synopsis... Broad troughing over the western US will continue as a compact shortwave trough moves across northern CA Thursday. 40-50 kt westerly flow will overspread the northern Great Basin. This will encourage dry downslope flow across parts of western NV. At the same time, continued monsoon moisture will allow widespread showers and thunderstorms over the Intermountain West. ...Northwest Great Basin... Continued westerly flow aloft will overspread the northern Great Basin Thursday afternoon. Dry downslope winds of 15-25 mph are expected, aided by the increasing winds aloft. Very warm temperatures, and the dry downslope trajectories, will support widespread RH values below 15%. The increase in surface winds amid a warm and dry boundary layer and dry fuels will support elevated wildfire spread potential Thursday. ...Western Slope... Another day of widespread showers and thunderstorms is expected across the eastern Great Basin and western Rockies Thursday. A continued surge of robust monsoon moisture (PWATS above 0.8 inches) will support a mixed mode of wet and occasionally dry storms. Widespread QPF of 0.1-0.25 inches in the preceding days suggest area fuels are likely to become less receptive to lightning ignitions with time. However, the coverage of storms does support at least isolated potential for dry strikes in receptive fuels across western CO/WY into eastern UT. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Wed Jul 02 2025 Valid 031200Z - 041200Z ...Synopsis... Broad troughing over the western US will continue as a compact shortwave trough moves across northern CA Thursday. 40-50 kt westerly flow will overspread the northern Great Basin. This will encourage dry downslope flow across parts of western NV. At the same time, continued monsoon moisture will allow widespread showers and thunderstorms over the Intermountain West. ...Northwest Great Basin... Continued westerly flow aloft will overspread the northern Great Basin Thursday afternoon. Dry downslope winds of 15-25 mph are expected, aided by the increasing winds aloft. Very warm temperatures, and the dry downslope trajectories, will support widespread RH values below 15%. The increase in surface winds amid a warm and dry boundary layer and dry fuels will support elevated wildfire spread potential Thursday. ...Western Slope... Another day of widespread showers and thunderstorms is expected across the eastern Great Basin and western Rockies Thursday. A continued surge of robust monsoon moisture (PWATS above 0.8 inches) will support a mixed mode of wet and occasionally dry storms. Widespread QPF of 0.1-0.25 inches in the preceding days suggest area fuels are likely to become less receptive to lightning ignitions with time. However, the coverage of storms does support at least isolated potential for dry strikes in receptive fuels across western CO/WY into eastern UT. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Wed Jul 02 2025 Valid 031200Z - 041200Z ...Synopsis... Broad troughing over the western US will continue as a compact shortwave trough moves across northern CA Thursday. 40-50 kt westerly flow will overspread the northern Great Basin. This will encourage dry downslope flow across parts of western NV. At the same time, continued monsoon moisture will allow widespread showers and thunderstorms over the Intermountain West. ...Northwest Great Basin... Continued westerly flow aloft will overspread the northern Great Basin Thursday afternoon. Dry downslope winds of 15-25 mph are expected, aided by the increasing winds aloft. Very warm temperatures, and the dry downslope trajectories, will support widespread RH values below 15%. The increase in surface winds amid a warm and dry boundary layer and dry fuels will support elevated wildfire spread potential Thursday. ...Western Slope... Another day of widespread showers and thunderstorms is expected across the eastern Great Basin and western Rockies Thursday. A continued surge of robust monsoon moisture (PWATS above 0.8 inches) will support a mixed mode of wet and occasionally dry storms. Widespread QPF of 0.1-0.25 inches in the preceding days suggest area fuels are likely to become less receptive to lightning ignitions with time. However, the coverage of storms does support at least isolated potential for dry strikes in receptive fuels across western CO/WY into eastern UT. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Wed Jul 02 2025 Valid 031200Z - 041200Z ...Synopsis... Broad troughing over the western US will continue as a compact shortwave trough moves across northern CA Thursday. 40-50 kt westerly flow will overspread the northern Great Basin. This will encourage dry downslope flow across parts of western NV. At the same time, continued monsoon moisture will allow widespread showers and thunderstorms over the Intermountain West. ...Northwest Great Basin... Continued westerly flow aloft will overspread the northern Great Basin Thursday afternoon. Dry downslope winds of 15-25 mph are expected, aided by the increasing winds aloft. Very warm temperatures, and the dry downslope trajectories, will support widespread RH values below 15%. The increase in surface winds amid a warm and dry boundary layer and dry fuels will support elevated wildfire spread potential Thursday. ...Western Slope... Another day of widespread showers and thunderstorms is expected across the eastern Great Basin and western Rockies Thursday. A continued surge of robust monsoon moisture (PWATS above 0.8 inches) will support a mixed mode of wet and occasionally dry storms. Widespread QPF of 0.1-0.25 inches in the preceding days suggest area fuels are likely to become less receptive to lightning ignitions with time. However, the coverage of storms does support at least isolated potential for dry strikes in receptive fuels across western CO/WY into eastern UT. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Wed Jul 02 2025 Valid 031200Z - 041200Z ...Synopsis... Broad troughing over the western US will continue as a compact shortwave trough moves across northern CA Thursday. 40-50 kt westerly flow will overspread the northern Great Basin. This will encourage dry downslope flow across parts of western NV. At the same time, continued monsoon moisture will allow widespread showers and thunderstorms over the Intermountain West. ...Northwest Great Basin... Continued westerly flow aloft will overspread the northern Great Basin Thursday afternoon. Dry downslope winds of 15-25 mph are expected, aided by the increasing winds aloft. Very warm temperatures, and the dry downslope trajectories, will support widespread RH values below 15%. The increase in surface winds amid a warm and dry boundary layer and dry fuels will support elevated wildfire spread potential Thursday. ...Western Slope... Another day of widespread showers and thunderstorms is expected across the eastern Great Basin and western Rockies Thursday. A continued surge of robust monsoon moisture (PWATS above 0.8 inches) will support a mixed mode of wet and occasionally dry storms. Widespread QPF of 0.1-0.25 inches in the preceding days suggest area fuels are likely to become less receptive to lightning ignitions with time. However, the coverage of storms does support at least isolated potential for dry strikes in receptive fuels across western CO/WY into eastern UT. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Wed Jul 02 2025 Valid 021200Z - 031200Z ...Synopsis... Mid-level troughing is forecast to slowly progress across central CA today, while another trough moves onshore across WA. Decreasing heights over the Northwest will continue to provide southerly transport of monsoon moisture into portions of the Great Basin and Intermountain West, where numerous thunderstorms are likely. Dry and breezy conditions will also be likely over the Cascades and western Columbia Basin. ...Lee of the Cascades... Increasing flow aloft ahead of the Pacific trough will favor dry downslope winds across the Cascades and western Columbia Basin. With daytime temperatures well into the 90s F, deep mixing will promote low boundary layer RH of 15-20%. With downslope winds of 15-25 mph, widespread elevated fire-weather conditions are likely on the lee slopes and through the gaps of the higher terrain. Some localized critical conditions are also possible where the terrain-enhanced winds and locally drier conditions may develop for a few hours this afternoon. ...Great Basin and northern Rockies Dry Thunder... East of the upper low, widespread thunderstorm activity is expected across the Great Basin and western slopes of the Rockies. A monsoon surge of 0.8 to 1.0 inch PWATs will lift northward across central/eastern NV into UT and western CO/WY. Weak ascent from the trough, along with diurnal heating of the terrain will result in scattered to numerous high-based showers and thunderstorms by early afternoon. Additional storms are likely along a cold front across ID and western MT. Given the increasing moisture content and continued southerly flow, some wetting rainfall is expected from training rounds of thunderstorms. A mix of wet and dry thunderstorms will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. This appears most likely across parts of eastern UT and western CO where less wetting rainfall is expected. Though isolated dry strikes are possible over the entire IsoDryT area. ...Northern OR/Southern CA... Scattered thunderstorms are again expected ahead of the upper low. A few of these storms may be drier with 30+ kt of southerly flow and relatively deeply mixed boundary layers. While a few dry strikes are possible outside of the heavier cores, recent QPE estimates of 0.5 to 1 inches indicate area fuels have likely been tempered to some degree. This suggests the threat for dry lightning is below IsoDryT thresholds. ..Lyons.. 07/02/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more