Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Aug 16 2025 Valid 162000Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT OVER PART OF SD...AND THIS AFTERNOON THROUGH TONIGHT OVER SOUTHEAST MN...SOUTHERN WI...AND NORTHERN IL... ...SUMMARY... Scattered strong/severe thunderstorms are possible today into tonight across parts of the northern Great Plains into the Midwest and Great Lakes regions. ...20Z Update... The prior forecast reasoning remains valid. Severe probabilities were reduced in parts of northern/central Wisconsin where prior convection has stabilized the boundary layer. Elsewhere, only minor changes were made to the general thunderstorm forecast based on current observational trends. See the previous discussion as well as MCDs 1965/1966 for additional information. ..Wendt.. 08/16/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 16 2025/ ...Upper Midwest into the Mid MS Valley and Upper Great Lakes Region... An expansive MCS continues to move eastward across the Upper Midwest, with a well-defined MCV evident in radar imagery over the central WI/MN border vicinity. This MCS has continued to gradually weaken throughout the morning, but a few strong updrafts persist along its southeastern periphery over central WI. This portion of the MCS is on the far northeastern periphery of the plume of steeper mid-level lapse rates that extends from the northern/central High Plains across the central Plains and into the Mid MS Valley. This plume is observable in the 12Z sounding from DVN and ILX, which sampled 700-500 mb lapse rates of 7.8 and 7.2 deg C per km, respectively. Dewpoints downstream across southern WI, northern IL, and northern IN are in the low 70s, with upper 60s dewpoints also covering much of southern Lower MI. The combination of ample low-level moisture and steep mid-level lapse rates will result in strong to very strong buoyancy to the south of the MCS from the MN/IA border into northern/central IL. Given the lack of a well-defined surface boundary and negligible large-scale ascent, additional thunderstorm development will be associated with outflow from with the MCS, which results in greater-than-average uncertainty for the Day 1 period. Ample moisture and buoyancy downstream of the leading edge of the MCS suggests the greater severe potential this afternoon/evening will likely be associated with redevelopment/reintensification of the MCS. Additionally, even if reintensification does not occur along the leading edge of the MCS this afternoon, most guidance suggests redevelopment does eventually occur this evening along the southern periphery of the MCV circulation as it moves into northern/central WI. Increased severe-wind probabilities (i.e. 15%) were introduced with this outlook to cover both of these potential scenarios. A small 15% hail probability was introduce to cover potential for later evening storms atop the outflow as well. Storms are possible into northern IN and the Lower MI this afternoon and evening as well, but the lower buoyancy should temper the overall coverage and magnitude in these areas. ...SD and Vicinity... A well-defined but rather weak shortwave trough is currently moving through western CO/western WY, and will continue northeastward into eastern WY/western Dakotas by this evening. Similar to yesterday, high-based storms will develop ahead of the approaching shortwave and intensify as they move eastward into a progressively more moist/unstable air mass over west-central SD. Upscale growth into another nocturnal MCS is forecast by most guidance, with the MCS tracking northeastward across western/central SD tonight. Strong to severe gusts are possible with this potential MCS across much of western/central SD. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Aug 16 2025 Valid 162000Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT OVER PART OF SD...AND THIS AFTERNOON THROUGH TONIGHT OVER SOUTHEAST MN...SOUTHERN WI...AND NORTHERN IL... ...SUMMARY... Scattered strong/severe thunderstorms are possible today into tonight across parts of the northern Great Plains into the Midwest and Great Lakes regions. ...20Z Update... The prior forecast reasoning remains valid. Severe probabilities were reduced in parts of northern/central Wisconsin where prior convection has stabilized the boundary layer. Elsewhere, only minor changes were made to the general thunderstorm forecast based on current observational trends. See the previous discussion as well as MCDs 1965/1966 for additional information. ..Wendt.. 08/16/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 16 2025/ ...Upper Midwest into the Mid MS Valley and Upper Great Lakes Region... An expansive MCS continues to move eastward across the Upper Midwest, with a well-defined MCV evident in radar imagery over the central WI/MN border vicinity. This MCS has continued to gradually weaken throughout the morning, but a few strong updrafts persist along its southeastern periphery over central WI. This portion of the MCS is on the far northeastern periphery of the plume of steeper mid-level lapse rates that extends from the northern/central High Plains across the central Plains and into the Mid MS Valley. This plume is observable in the 12Z sounding from DVN and ILX, which sampled 700-500 mb lapse rates of 7.8 and 7.2 deg C per km, respectively. Dewpoints downstream across southern WI, northern IL, and northern IN are in the low 70s, with upper 60s dewpoints also covering much of southern Lower MI. The combination of ample low-level moisture and steep mid-level lapse rates will result in strong to very strong buoyancy to the south of the MCS from the MN/IA border into northern/central IL. Given the lack of a well-defined surface boundary and negligible large-scale ascent, additional thunderstorm development will be associated with outflow from with the MCS, which results in greater-than-average uncertainty for the Day 1 period. Ample moisture and buoyancy downstream of the leading edge of the MCS suggests the greater severe potential this afternoon/evening will likely be associated with redevelopment/reintensification of the MCS. Additionally, even if reintensification does not occur along the leading edge of the MCS this afternoon, most guidance suggests redevelopment does eventually occur this evening along the southern periphery of the MCV circulation as it moves into northern/central WI. Increased severe-wind probabilities (i.e. 15%) were introduced with this outlook to cover both of these potential scenarios. A small 15% hail probability was introduce to cover potential for later evening storms atop the outflow as well. Storms are possible into northern IN and the Lower MI this afternoon and evening as well, but the lower buoyancy should temper the overall coverage and magnitude in these areas. ...SD and Vicinity... A well-defined but rather weak shortwave trough is currently moving through western CO/western WY, and will continue northeastward into eastern WY/western Dakotas by this evening. Similar to yesterday, high-based storms will develop ahead of the approaching shortwave and intensify as they move eastward into a progressively more moist/unstable air mass over west-central SD. Upscale growth into another nocturnal MCS is forecast by most guidance, with the MCS tracking northeastward across western/central SD tonight. Strong to severe gusts are possible with this potential MCS across much of western/central SD. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Aug 16 2025 Valid 162000Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT OVER PART OF SD...AND THIS AFTERNOON THROUGH TONIGHT OVER SOUTHEAST MN...SOUTHERN WI...AND NORTHERN IL... ...SUMMARY... Scattered strong/severe thunderstorms are possible today into tonight across parts of the northern Great Plains into the Midwest and Great Lakes regions. ...20Z Update... The prior forecast reasoning remains valid. Severe probabilities were reduced in parts of northern/central Wisconsin where prior convection has stabilized the boundary layer. Elsewhere, only minor changes were made to the general thunderstorm forecast based on current observational trends. See the previous discussion as well as MCDs 1965/1966 for additional information. ..Wendt.. 08/16/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 16 2025/ ...Upper Midwest into the Mid MS Valley and Upper Great Lakes Region... An expansive MCS continues to move eastward across the Upper Midwest, with a well-defined MCV evident in radar imagery over the central WI/MN border vicinity. This MCS has continued to gradually weaken throughout the morning, but a few strong updrafts persist along its southeastern periphery over central WI. This portion of the MCS is on the far northeastern periphery of the plume of steeper mid-level lapse rates that extends from the northern/central High Plains across the central Plains and into the Mid MS Valley. This plume is observable in the 12Z sounding from DVN and ILX, which sampled 700-500 mb lapse rates of 7.8 and 7.2 deg C per km, respectively. Dewpoints downstream across southern WI, northern IL, and northern IN are in the low 70s, with upper 60s dewpoints also covering much of southern Lower MI. The combination of ample low-level moisture and steep mid-level lapse rates will result in strong to very strong buoyancy to the south of the MCS from the MN/IA border into northern/central IL. Given the lack of a well-defined surface boundary and negligible large-scale ascent, additional thunderstorm development will be associated with outflow from with the MCS, which results in greater-than-average uncertainty for the Day 1 period. Ample moisture and buoyancy downstream of the leading edge of the MCS suggests the greater severe potential this afternoon/evening will likely be associated with redevelopment/reintensification of the MCS. Additionally, even if reintensification does not occur along the leading edge of the MCS this afternoon, most guidance suggests redevelopment does eventually occur this evening along the southern periphery of the MCV circulation as it moves into northern/central WI. Increased severe-wind probabilities (i.e. 15%) were introduced with this outlook to cover both of these potential scenarios. A small 15% hail probability was introduce to cover potential for later evening storms atop the outflow as well. Storms are possible into northern IN and the Lower MI this afternoon and evening as well, but the lower buoyancy should temper the overall coverage and magnitude in these areas. ...SD and Vicinity... A well-defined but rather weak shortwave trough is currently moving through western CO/western WY, and will continue northeastward into eastern WY/western Dakotas by this evening. Similar to yesterday, high-based storms will develop ahead of the approaching shortwave and intensify as they move eastward into a progressively more moist/unstable air mass over west-central SD. Upscale growth into another nocturnal MCS is forecast by most guidance, with the MCS tracking northeastward across western/central SD tonight. Strong to severe gusts are possible with this potential MCS across much of western/central SD. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Aug 16 2025 Valid 162000Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT OVER PART OF SD...AND THIS AFTERNOON THROUGH TONIGHT OVER SOUTHEAST MN...SOUTHERN WI...AND NORTHERN IL... ...SUMMARY... Scattered strong/severe thunderstorms are possible today into tonight across parts of the northern Great Plains into the Midwest and Great Lakes regions. ...20Z Update... The prior forecast reasoning remains valid. Severe probabilities were reduced in parts of northern/central Wisconsin where prior convection has stabilized the boundary layer. Elsewhere, only minor changes were made to the general thunderstorm forecast based on current observational trends. See the previous discussion as well as MCDs 1965/1966 for additional information. ..Wendt.. 08/16/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 16 2025/ ...Upper Midwest into the Mid MS Valley and Upper Great Lakes Region... An expansive MCS continues to move eastward across the Upper Midwest, with a well-defined MCV evident in radar imagery over the central WI/MN border vicinity. This MCS has continued to gradually weaken throughout the morning, but a few strong updrafts persist along its southeastern periphery over central WI. This portion of the MCS is on the far northeastern periphery of the plume of steeper mid-level lapse rates that extends from the northern/central High Plains across the central Plains and into the Mid MS Valley. This plume is observable in the 12Z sounding from DVN and ILX, which sampled 700-500 mb lapse rates of 7.8 and 7.2 deg C per km, respectively. Dewpoints downstream across southern WI, northern IL, and northern IN are in the low 70s, with upper 60s dewpoints also covering much of southern Lower MI. The combination of ample low-level moisture and steep mid-level lapse rates will result in strong to very strong buoyancy to the south of the MCS from the MN/IA border into northern/central IL. Given the lack of a well-defined surface boundary and negligible large-scale ascent, additional thunderstorm development will be associated with outflow from with the MCS, which results in greater-than-average uncertainty for the Day 1 period. Ample moisture and buoyancy downstream of the leading edge of the MCS suggests the greater severe potential this afternoon/evening will likely be associated with redevelopment/reintensification of the MCS. Additionally, even if reintensification does not occur along the leading edge of the MCS this afternoon, most guidance suggests redevelopment does eventually occur this evening along the southern periphery of the MCV circulation as it moves into northern/central WI. Increased severe-wind probabilities (i.e. 15%) were introduced with this outlook to cover both of these potential scenarios. A small 15% hail probability was introduce to cover potential for later evening storms atop the outflow as well. Storms are possible into northern IN and the Lower MI this afternoon and evening as well, but the lower buoyancy should temper the overall coverage and magnitude in these areas. ...SD and Vicinity... A well-defined but rather weak shortwave trough is currently moving through western CO/western WY, and will continue northeastward into eastern WY/western Dakotas by this evening. Similar to yesterday, high-based storms will develop ahead of the approaching shortwave and intensify as they move eastward into a progressively more moist/unstable air mass over west-central SD. Upscale growth into another nocturnal MCS is forecast by most guidance, with the MCS tracking northeastward across western/central SD tonight. Strong to severe gusts are possible with this potential MCS across much of western/central SD. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...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 0257 PM CDT Sat Aug 16 2025 Valid 171200Z - 181200Z ...Northern Great Basin, Southern Idaho and southwestern Montana... No significant changes were needed for isolated dry thunderstorm threat area across the northern Great Basin into far southwestern MT. Pacific moisture plume with PWATs reaching up to 1.00 inch along a cold front combined with higher terrain convection in the afternoon will still support areas a mix of wet/dry thunderstorms Sunday. With elevated mid-level flow remaining in place from southeastern OR into southwestern MT, faster northeast storm motions will limit overall rainfall where fuels remain drier, increasing lightning ignition potential. ...Southern Nevada into western Utah... Amplifying mid-level trough over the Northwest along with the arrival a subtle mid-level wave should enhance south-southwesterly surface flow across southern NV into western UT. Fuels remain very dry and receptive to spread, with some record to near record high ERC values remaining across portions of the Great Basin along with minimal rainfall over the past several days. Southwest winds of up to 15 mph with relative humidity falling to as low as 10 percent will bring elevated fire weather conditions to southern NV and western UT Sunday where Elevated highlights have been introduced. ..Williams.. 08/16/2025 .PREV DISCUSSION... /ISSUED 0204 AM CDT Sat Aug 16 2025/ ...Synopsis... Across the US, broad ridging is forecast to expand while troughing consolidates over the West. As height aloft build, very warm surface temperatures are expected over parts of the southern and Southwestern CONUS. A belt of stronger flow aloft will impinge on the northern Rockies as the trough and a weak surface cold front approach. Monsoon moisture should support dry thunderstorms, while light winds and dry conditions will persist elsewhere Sunday. ...Northern Rockies Dry Thunder... Troughing should continue to intensify as it moves into the Great Basin and Rockies Sunday, as a cold front moves in from the west. This will allow for additional monsoon moisture to filter northward, supporting scattered showers and thunderstorms through the afternoon. Despite PWATs climbing to near 0.8 to 1 inches, a mix of wet and dry thunderstorms is expected ahead of the front from northern CA into the Northern Rockies. While not as dry as previous days, stronger flow aloft is expected ahead of the deepening trough. This should allow for a favorable alignment of drier/more receptive fuels and faster northeast thunderstorm motions to limit rainfall across northern NV into central ID and western MT. Thus, isolated dry lightning and ignitions are likely to remain a concern across the receptive fuels beds of the northern Great Basin and Rockies Sunday. ...Southern NV into southwest UT South of the western US troughing and stronger flow aloft, another day of dry and locally breezy conditions is expected over parts of the southern Great Basin. While displaced from the stronger flow, localized 15 mph surface winds and low RH below 15% are likely across southern NV and southwest UT. With area fuels very dry and receptive, some locally elevated fire-weather conditions are possible, though widespread occurrence is unlikely owing to the modest winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0596 Status Updates
STATUS REPORT ON WW 596 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..08/16/25 ATTN...WFO...LOT...DVN...MKX... STATUS REPORT FOR WS 596 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-031-037-043-089-093-097-111-141-177-197-201-162040- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE COOK DE KALB DUPAGE KANE KENDALL LAKE MCHENRY OGLE STEPHENSON WILL WINNEBAGO INC089-127-162040- IN . INDIANA COUNTIES INCLUDED ARE LAKE PORTER WIC045-055-059-079-101-105-127-133-162040- WI . WISCONSIN COUNTIES INCLUDED ARE GREEN JEFFERSON KENOSHA MILWAUKEE RACINE ROCK Read more