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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Mon Jun 30 2025 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An isolated severe storm may also occur over parts of the central High Plains. ...Synopsis... A mid-level trough will traverse the Northeast as an upper ridge persists over the central U.S. and a mid-level low meanders over CA tomorrow (Tuesday). The East Coast mid-level trough will encourage the eastward advancement of a cold front, which will provide enough lift for scattered to widespread thunderstorm development across the Carolinas into the Northeast. Rich low-level moisture preceding the front will encourage enough buoyancy, amid marginal but adequate vertical wind shear, to support strong thunderstorms, some of which could be severe. A couple of strong to severe storms are possible along the periphery of the upper ridge over parts of the northern Rockies into the central High Plains. ...Northeast into the Southeast... As the surface cold front advances eastward across the eastern U.S., surface temperatures will warm into the 80s F to near 90 F, amid 70+ F dewpoints from the Southeast to the Mid-Atlantic, boosting SBCAPE into the 2000-3500 J/kg range by afternoon peak heating. Relatively poor mid-level lapse rates will limit CAPE to tall/thin profiles. However, the magnitude of buoyancy, combined with widespread thunderstorm coverage over a large area, will foster ample opportunity for at least isolated damaging gusts with wet downbursts, from the Southeast to New England. A more concentrated area of damaging gust potential exists over parts of the Mid_Atlantic, where a Category 2/Slight Risk remains in place. Here, line segments are expected to organize amid a region of maximum buoyancy and 30 kts of effective bulk shear, driven by stronger west-southwesterly mid-level flow grazing the area. ...Portions of the Northern Rockies... Mid-level monsoonal moisture is forecast to crest the upper ridge amid modest 500 mb west-southwesterly flow over parts of the Northern Rockies, where guidance consensus shows PWATs reaching 0.8 inches in spots. High-based thunderstorms will develop by afternoon peak heating, atop a well-mixed boundary layer extending to 500 mb via inverted-v thermodynamic profiles. The aforementioned mid-level moisture, combined with steep tropospheric lapse rates, will support over 500 J/kg MLCAPE. This buoyancy may support robust enough updrafts and subsequent storm cores in an environment where ample evaporative cooling may take place to support isolated severe gusts. ...Central High Plains... Low-level upslope flow, along with strong diurnal heating, and the passage of a small impulse embedded in the upper ridge, will all serve as mechanisms for convective initiation tomorrow afternoon. Though storms should be isolated, they will develop amid 8 C/km low and mid-level lapse rates that will boost MLCAPE into the 1500-2500 J/kg range. Modest directional vertical wind shear will support somewhat curved/elongated hodographs and around 35 kts of effective bulk shear. As such, a few multicells/transient supercells may develop and produce isolated severe wind/hail. ..Squitieri.. 06/30/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...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 1155 AM CDT Mon Jun 30 2025 Valid 301700Z - 011200Z ...Northern California and Southwestern Oregon... An approaching mid-level trough, steep low-level lapse rates and increasing mid-level moisture and instability will aid a mix of wet/dry thunderstorm development across the higher terrain of northern California, with showers and thunderstorms propagating into southern Oregon along and east of the Cascades through this evening. Isolated dry thunderstorm highlights persist where new ignitions are possible atop dry fuels. ...Great Basin... The mid-level trough entering California and associated stronger southerly mid-level flow will overspread the Great Basin today. A deep, well-mixed boundary layer will facilitate gusty surface winds from the south of up to 25 mph across central Nevada, with sustained winds of around 15 mph. The enhanced winds along with low relative humidity will promote an elevated fire weather threat amid receptive fuels. ..Williams.. 06/30/2025 .PREV DISCUSSION... /ISSUED 0215 AM CDT Mon Jun 30 2025/ ...Synopsis... Across the US, sub-tropical ridging will build over the Plains, keeping stronger flow aloft displaced to the north while an upper low will overspread portions of the West Coast. Ahead of the low, breezy southerly winds will advect monsoon moisture northward into parts of CA and OR. Dry thunderstorms and dry/breezy conditions appear likely to support elevated fire-weather potential across the Northwest and Great Basin today. ...Northwest... Weak ascent from an approaching upper trough will allow for isolated to widely scattered thunderstorms across northern CA and southern OR through tonight. Strong heating and dry sub-cloud layers with steep lapse rates below 500mb will support a mixed wet/dry thunderstorm environment capable of occasional dry lightning strikes. Additionally, erratic outflow winds are likely near storms. The increased potential for dry lightning atop receptive fuels, warrants continuation of IsodryT probabilities where fire starts are possible. ...Great Basin... Beneath the upper ridge, very hot surface temperatures are expected over parts of NV and western UT. Southerly surface winds may gust to 15-20 mph through the afternoon, concurrent with widespread RH values below 15%. The presence of breezy low-level winds and the hot/dry conditions will overlap with a progressively drier and receptive fuels across NV. This could support a few hours of elevated fire-weather potential through this evening. ...Please see www.spc.noaa.gov/fire for graphic product... Read more