Aggregator

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CDT Tue Aug 12 2025 Valid 151200Z - 201200Z ...DISCUSSION... From Friday/D4 into Saturday/D5, an upper low will move from Manitoba across Hudson Bay and into Quebec. Moderate midlevel westerlies will exist over the far northern Plains to Upper Great Lakes during this period, with gradual weakening. An upper high will also be centered over the mid MS Valley, while a weak midlevel trough with cool air aloft slowly departs the Great Basin. At the surface, a front is forecast to stall on Friday/D4 from northern NE across southern MN and into northern WI, with a moist and unstable air mass remaining to the south. This front will remain over roughly the same zone into Saturday/D5, and perhaps as late as Sunday/D6. Given that the moist and unstable air mass will persist over parts of the northern Plains/Upper MS Valley, and minor ripples in the flow are hinted at by several models, areas of storms are expected. However, storm/MCS corridors are difficult to pinpoint this far out. In general, the area from SD into WI will bear watching for wind potential. From Sunday/D6 onward, an upper ridge is expected to build over much of the western and central states, with a reduction in severe potential overall. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Tue Aug 12 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PRIMARILY FROM EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Severe storms producing hail and wind are possible mainly from eastern North Dakota into northwest Minnesota Thursday afternoon and evening. ...Discussion... On Thursday, a shortwave trough will continue eastward into the northern Plains during the day, with primary upper low well north into Canada. The southern periphery of this wave will move across ND and northern MN late day and overnight, with cooling aloft and increasing midlevel winds of 40-50 kt. At the surface, a cold front will be located from eastern ND into western SD during the afternoon, and will move into northern MN overnight. Southwest winds will bring moisture northward ahead of the front, with moderate instability forecast. Effective shear of 40-50 kt will develop late as the upper wave approaches and low-level jet increases. Storms are most likely to form around 00Z along the deeper cold front over eastern ND, and progress across northwest MN during the evening. Large hail appears likely as storm mode should be cellular. Strong heating into central SD may also yield isolated cells a bit farther south than forecast by many models, also with large hail threat. ..Jewell.. 08/12/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Tue Aug 12 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PRIMARILY FROM EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Severe storms producing hail and wind are possible mainly from eastern North Dakota into northwest Minnesota Thursday afternoon and evening. ...Discussion... On Thursday, a shortwave trough will continue eastward into the northern Plains during the day, with primary upper low well north into Canada. The southern periphery of this wave will move across ND and northern MN late day and overnight, with cooling aloft and increasing midlevel winds of 40-50 kt. At the surface, a cold front will be located from eastern ND into western SD during the afternoon, and will move into northern MN overnight. Southwest winds will bring moisture northward ahead of the front, with moderate instability forecast. Effective shear of 40-50 kt will develop late as the upper wave approaches and low-level jet increases. Storms are most likely to form around 00Z along the deeper cold front over eastern ND, and progress across northwest MN during the evening. Large hail appears likely as storm mode should be cellular. Strong heating into central SD may also yield isolated cells a bit farther south than forecast by many models, also with large hail threat. ..Jewell.. 08/12/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Tue Aug 12 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PRIMARILY FROM EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Severe storms producing hail and wind are possible mainly from eastern North Dakota into northwest Minnesota Thursday afternoon and evening. ...Discussion... On Thursday, a shortwave trough will continue eastward into the northern Plains during the day, with primary upper low well north into Canada. The southern periphery of this wave will move across ND and northern MN late day and overnight, with cooling aloft and increasing midlevel winds of 40-50 kt. At the surface, a cold front will be located from eastern ND into western SD during the afternoon, and will move into northern MN overnight. Southwest winds will bring moisture northward ahead of the front, with moderate instability forecast. Effective shear of 40-50 kt will develop late as the upper wave approaches and low-level jet increases. Storms are most likely to form around 00Z along the deeper cold front over eastern ND, and progress across northwest MN during the evening. Large hail appears likely as storm mode should be cellular. Strong heating into central SD may also yield isolated cells a bit farther south than forecast by many models, also with large hail threat. ..Jewell.. 08/12/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Tue Aug 12 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PRIMARILY FROM EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Severe storms producing hail and wind are possible mainly from eastern North Dakota into northwest Minnesota Thursday afternoon and evening. ...Discussion... On Thursday, a shortwave trough will continue eastward into the northern Plains during the day, with primary upper low well north into Canada. The southern periphery of this wave will move across ND and northern MN late day and overnight, with cooling aloft and increasing midlevel winds of 40-50 kt. At the surface, a cold front will be located from eastern ND into western SD during the afternoon, and will move into northern MN overnight. Southwest winds will bring moisture northward ahead of the front, with moderate instability forecast. Effective shear of 40-50 kt will develop late as the upper wave approaches and low-level jet increases. Storms are most likely to form around 00Z along the deeper cold front over eastern ND, and progress across northwest MN during the evening. Large hail appears likely as storm mode should be cellular. Strong heating into central SD may also yield isolated cells a bit farther south than forecast by many models, also with large hail threat. ..Jewell.. 08/12/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Tue Aug 12 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PRIMARILY FROM EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Severe storms producing hail and wind are possible mainly from eastern North Dakota into northwest Minnesota Thursday afternoon and evening. ...Discussion... On Thursday, a shortwave trough will continue eastward into the northern Plains during the day, with primary upper low well north into Canada. The southern periphery of this wave will move across ND and northern MN late day and overnight, with cooling aloft and increasing midlevel winds of 40-50 kt. At the surface, a cold front will be located from eastern ND into western SD during the afternoon, and will move into northern MN overnight. Southwest winds will bring moisture northward ahead of the front, with moderate instability forecast. Effective shear of 40-50 kt will develop late as the upper wave approaches and low-level jet increases. Storms are most likely to form around 00Z along the deeper cold front over eastern ND, and progress across northwest MN during the evening. Large hail appears likely as storm mode should be cellular. Strong heating into central SD may also yield isolated cells a bit farther south than forecast by many models, also with large hail threat. ..Jewell.. 08/12/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will become more widespread across the West on Wednesday as a strong upper-level wave moves across the region. Short to medium-range guidance shows reasonably good agreement in the southeastward progression of an amplifying upper wave (currently over the northeast Pacific) across the Pacific Northwest and northern Rockies through Wednesday afternoon/evening. Strengthening downslope winds off the Cascades and Sierra Nevada will promote windy and dry conditions across western NV into eastern WA/OR. Further east, robust surface pressure falls attendant to the upper wave will promote strengthening surface winds across a broad swath of the eastern Great Basin and central/northern Rockies. Latest ensemble guidance suggests sustained winds in the upper teens are most probable, though some regions may see sustained winds between 20-25 mph. Spread between ensemble and deterministic solutions limits confidence on where such corridors of higher winds will emerge, but given high probabilities for sub-15% RH, swaths of critical fire weather conditions appear possible. Elevated fire weather conditions may emerge across portions of northern MT as well, but recent fuel guidance suggests fuels are not overly receptive across this region (though fuel trends will be monitored given the forecast for dry/windy conditions). Dry thunderstorms are also possible across the Great Basin Wednesday afternoon. A plume of mid-level moisture moving northward off the CA coast will likely phase with the passage of the upper wave and support adequate buoyancy for high-based convection across portions of east-central CA, central NV, and perhaps into southern ID. Strong diurnal heating and mixing will push LCL heights to above 4 km, which, in conjunction with 20 knot storm motions, will limit precipitation totals and favor dry thunderstorms. While coverage of thunderstorms may be limited, dry fuels across the region should support the fire weather concern. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 AM CDT Tue Aug 12 2025 Valid 121200Z - 131200Z ...Synopsis... Fire weather concerns will be focused across parts of central and eastern Arizona this afternoon, though more local concerns may emerge across portions of Oregon. ...Central to eastern Arizona... A mixture of wet and dry thunderstorms is expected again this afternoon along the Mogollon Rim. An evening 00z sounding from ABQ sampled a very deep, dry boundary layer along with steep mid-level lapse rates and PWAT values near 0.5 inch. This dry, but weakly buoyant, thermodynamic environment on the northern fringe of the deeper monsoonal moisture yielded a mix of wet and dry thunderstorms across the region yesterday. Similar conditions are likely today and should pose a fire weather concern over areas with receptive fuels. Dry thunderstorms are possible further east into western NM, but recent rainfall and improved fuels should mitigate the fire risk. ...Oregon... A weak mid-level wave is noted in early-morning water-vapor imagery off the Pacific Northwest coast. This feature will migrate east through the day and overspread the Cascades through peak heating. The associated westerly mid-level flow will not be overly strong, but will still induce a downslope flow regime on the eastern slopes of the Cascades. Compressional heating/drying, coupled with peak heating and full insolation, will promote RH reductions between 10-20%. Sustained winds between 10-15 mph appear most probable based on latest ensemble consensus, but gusts between 20-25 mph (especially wind-prone locations within the terrain) are possible. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 AM CDT Tue Aug 12 2025 Valid 121200Z - 131200Z ...Synopsis... Fire weather concerns will be focused across parts of central and eastern Arizona this afternoon, though more local concerns may emerge across portions of Oregon. ...Central to eastern Arizona... A mixture of wet and dry thunderstorms is expected again this afternoon along the Mogollon Rim. An evening 00z sounding from ABQ sampled a very deep, dry boundary layer along with steep mid-level lapse rates and PWAT values near 0.5 inch. This dry, but weakly buoyant, thermodynamic environment on the northern fringe of the deeper monsoonal moisture yielded a mix of wet and dry thunderstorms across the region yesterday. Similar conditions are likely today and should pose a fire weather concern over areas with receptive fuels. Dry thunderstorms are possible further east into western NM, but recent rainfall and improved fuels should mitigate the fire risk. ...Oregon... A weak mid-level wave is noted in early-morning water-vapor imagery off the Pacific Northwest coast. This feature will migrate east through the day and overspread the Cascades through peak heating. The associated westerly mid-level flow will not be overly strong, but will still induce a downslope flow regime on the eastern slopes of the Cascades. Compressional heating/drying, coupled with peak heating and full insolation, will promote RH reductions between 10-20%. Sustained winds between 10-15 mph appear most probable based on latest ensemble consensus, but gusts between 20-25 mph (especially wind-prone locations within the terrain) are possible. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 AM CDT Tue Aug 12 2025 Valid 121200Z - 131200Z ...Synopsis... Fire weather concerns will be focused across parts of central and eastern Arizona this afternoon, though more local concerns may emerge across portions of Oregon. ...Central to eastern Arizona... A mixture of wet and dry thunderstorms is expected again this afternoon along the Mogollon Rim. An evening 00z sounding from ABQ sampled a very deep, dry boundary layer along with steep mid-level lapse rates and PWAT values near 0.5 inch. This dry, but weakly buoyant, thermodynamic environment on the northern fringe of the deeper monsoonal moisture yielded a mix of wet and dry thunderstorms across the region yesterday. Similar conditions are likely today and should pose a fire weather concern over areas with receptive fuels. Dry thunderstorms are possible further east into western NM, but recent rainfall and improved fuels should mitigate the fire risk. ...Oregon... A weak mid-level wave is noted in early-morning water-vapor imagery off the Pacific Northwest coast. This feature will migrate east through the day and overspread the Cascades through peak heating. The associated westerly mid-level flow will not be overly strong, but will still induce a downslope flow regime on the eastern slopes of the Cascades. Compressional heating/drying, coupled with peak heating and full insolation, will promote RH reductions between 10-20%. Sustained winds between 10-15 mph appear most probable based on latest ensemble consensus, but gusts between 20-25 mph (especially wind-prone locations within the terrain) are possible. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 AM CDT Tue Aug 12 2025 Valid 121200Z - 131200Z ...Synopsis... Fire weather concerns will be focused across parts of central and eastern Arizona this afternoon, though more local concerns may emerge across portions of Oregon. ...Central to eastern Arizona... A mixture of wet and dry thunderstorms is expected again this afternoon along the Mogollon Rim. An evening 00z sounding from ABQ sampled a very deep, dry boundary layer along with steep mid-level lapse rates and PWAT values near 0.5 inch. This dry, but weakly buoyant, thermodynamic environment on the northern fringe of the deeper monsoonal moisture yielded a mix of wet and dry thunderstorms across the region yesterday. Similar conditions are likely today and should pose a fire weather concern over areas with receptive fuels. Dry thunderstorms are possible further east into western NM, but recent rainfall and improved fuels should mitigate the fire risk. ...Oregon... A weak mid-level wave is noted in early-morning water-vapor imagery off the Pacific Northwest coast. This feature will migrate east through the day and overspread the Cascades through peak heating. The associated westerly mid-level flow will not be overly strong, but will still induce a downslope flow regime on the eastern slopes of the Cascades. Compressional heating/drying, coupled with peak heating and full insolation, will promote RH reductions between 10-20%. Sustained winds between 10-15 mph appear most probable based on latest ensemble consensus, but gusts between 20-25 mph (especially wind-prone locations within the terrain) are possible. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 AM CDT Tue Aug 12 2025 Valid 121200Z - 131200Z ...Synopsis... Fire weather concerns will be focused across parts of central and eastern Arizona this afternoon, though more local concerns may emerge across portions of Oregon. ...Central to eastern Arizona... A mixture of wet and dry thunderstorms is expected again this afternoon along the Mogollon Rim. An evening 00z sounding from ABQ sampled a very deep, dry boundary layer along with steep mid-level lapse rates and PWAT values near 0.5 inch. This dry, but weakly buoyant, thermodynamic environment on the northern fringe of the deeper monsoonal moisture yielded a mix of wet and dry thunderstorms across the region yesterday. Similar conditions are likely today and should pose a fire weather concern over areas with receptive fuels. Dry thunderstorms are possible further east into western NM, but recent rainfall and improved fuels should mitigate the fire risk. ...Oregon... A weak mid-level wave is noted in early-morning water-vapor imagery off the Pacific Northwest coast. This feature will migrate east through the day and overspread the Cascades through peak heating. The associated westerly mid-level flow will not be overly strong, but will still induce a downslope flow regime on the eastern slopes of the Cascades. Compressional heating/drying, coupled with peak heating and full insolation, will promote RH reductions between 10-20%. Sustained winds between 10-15 mph appear most probable based on latest ensemble consensus, but gusts between 20-25 mph (especially wind-prone locations within the terrain) are possible. ..Moore.. 08/12/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS CENTERED OVER SOUTH DAKOTA... ...SUMMARY... The evolution of an organized cluster of thunderstorms accompanied by strong to severe wind gusts appears possible across parts of central through eastern South Dakota by Wednesday evening. ...Discussion... As a low-amplitude shortwave trough progresses over the northern Rockies, a surface low will develop into southern SK, with a secondary low into western SD late in the day. Southerly low-level winds will develop over the Plains, with increasing 850 mb winds of 40-50 kt overnight from NE into SD. Initially, the air mass will be relatively dry. However, a plume of 60s F dewpoints will materialize across the mid MO Valley, with strong heating over the High Plains a near the surface trough. Storms may develop near 00Z over parts of SD near the Black Hills and near the surface low/lapse rate plume, with an initial hail risk. With time, storms should produce strong outflow, with a few severe gusts possible. Due to limited moisture, capping will become a mitigating factor after 00Z, and may preclude a more robust MCS. As such, a Marginal Risk remains valid for primarily isolated severe activity withing the broader zone of convection. ..Jewell.. 08/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS CENTERED OVER SOUTH DAKOTA... ...SUMMARY... The evolution of an organized cluster of thunderstorms accompanied by strong to severe wind gusts appears possible across parts of central through eastern South Dakota by Wednesday evening. ...Discussion... As a low-amplitude shortwave trough progresses over the northern Rockies, a surface low will develop into southern SK, with a secondary low into western SD late in the day. Southerly low-level winds will develop over the Plains, with increasing 850 mb winds of 40-50 kt overnight from NE into SD. Initially, the air mass will be relatively dry. However, a plume of 60s F dewpoints will materialize across the mid MO Valley, with strong heating over the High Plains a near the surface trough. Storms may develop near 00Z over parts of SD near the Black Hills and near the surface low/lapse rate plume, with an initial hail risk. With time, storms should produce strong outflow, with a few severe gusts possible. Due to limited moisture, capping will become a mitigating factor after 00Z, and may preclude a more robust MCS. As such, a Marginal Risk remains valid for primarily isolated severe activity withing the broader zone of convection. ..Jewell.. 08/12/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Tue Aug 12 2025 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS CENTERED OVER SOUTH DAKOTA... ...SUMMARY... The evolution of an organized cluster of thunderstorms accompanied by strong to severe wind gusts appears possible across parts of central through eastern South Dakota by Wednesday evening. ...Discussion... As a low-amplitude shortwave trough progresses over the northern Rockies, a surface low will develop into southern SK, with a secondary low into western SD late in the day. Southerly low-level winds will develop over the Plains, with increasing 850 mb winds of 40-50 kt overnight from NE into SD. Initially, the air mass will be relatively dry. However, a plume of 60s F dewpoints will materialize across the mid MO Valley, with strong heating over the High Plains a near the surface trough. Storms may develop near 00Z over parts of SD near the Black Hills and near the surface low/lapse rate plume, with an initial hail risk. With time, storms should produce strong outflow, with a few severe gusts possible. Due to limited moisture, capping will become a mitigating factor after 00Z, and may preclude a more robust MCS. As such, a Marginal Risk remains valid for primarily isolated severe activity withing the broader zone of convection. ..Jewell.. 08/12/2025 Read more