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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sat Sep 14 2024 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN TO FOUR CORNERS... ...SUMMARY... Isolated severe gusts and small to marginally severe hail will be possible on Monday afternoon to early evening across parts of the eastern Great Basin to Four Corners. ...Eastern Great Basin to the Four Corners... An amplified closed mid/upper low over northern/central CA at 12Z Monday should initially move east before curling northeast Monday night towards the NV/UT/ID border area. This will occur in response to a vigorous mid-level jet translating through the basal portion of the large-scale trough across the Desert Southwest into the eastern Great Basin. Surface cyclogenesis should be induced near the UT/NV border area, with a predominant meridional deep-layer flow regime near/just ahead of the low. Isolated to scattered thunderstorms should develop as modest steepening of mid-level lapse rates overspreads a deepening boundary layer during the afternoon. The strengthening synoptic flow regime coupled with inverted-v thermodynamic profiles west of the Wasatch Range may yield sporadic severe gusts with low-topped, high-based convection. Farther southeast towards the Four Corners, a more southwesterly mid to upper-flow regime should yield hodograph elongation, conditionally supporting splitting supercells. Warmer mid-level temperatures and correspondingly weaker lapse rates should temper parcel acceleration to an extent, but this may be offset by somewhat higher PW values. Marginally severe hail/gusts will be possible. ...Coastal Carolinas... Guidance has trended towards a greater signal for offshore subtropical or tropical cyclogenesis by Monday. Still, spread is quite large with the degree of amplification as NCEP guidance appears to be on the aggressive spectrum relative to non-NCEP models. With timing and spatial differences also large, will defer on a potential tornado threat highlight. ..Grams.. 09/14/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sat Sep 14 2024 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN TO FOUR CORNERS... ...SUMMARY... Isolated severe gusts and small to marginally severe hail will be possible on Monday afternoon to early evening across parts of the eastern Great Basin to Four Corners. ...Eastern Great Basin to the Four Corners... An amplified closed mid/upper low over northern/central CA at 12Z Monday should initially move east before curling northeast Monday night towards the NV/UT/ID border area. This will occur in response to a vigorous mid-level jet translating through the basal portion of the large-scale trough across the Desert Southwest into the eastern Great Basin. Surface cyclogenesis should be induced near the UT/NV border area, with a predominant meridional deep-layer flow regime near/just ahead of the low. Isolated to scattered thunderstorms should develop as modest steepening of mid-level lapse rates overspreads a deepening boundary layer during the afternoon. The strengthening synoptic flow regime coupled with inverted-v thermodynamic profiles west of the Wasatch Range may yield sporadic severe gusts with low-topped, high-based convection. Farther southeast towards the Four Corners, a more southwesterly mid to upper-flow regime should yield hodograph elongation, conditionally supporting splitting supercells. Warmer mid-level temperatures and correspondingly weaker lapse rates should temper parcel acceleration to an extent, but this may be offset by somewhat higher PW values. Marginally severe hail/gusts will be possible. ...Coastal Carolinas... Guidance has trended towards a greater signal for offshore subtropical or tropical cyclogenesis by Monday. Still, spread is quite large with the degree of amplification as NCEP guidance appears to be on the aggressive spectrum relative to non-NCEP models. With timing and spatial differences also large, will defer on a potential tornado threat highlight. ..Grams.. 09/14/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sat Sep 14 2024 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN TO FOUR CORNERS... ...SUMMARY... Isolated severe gusts and small to marginally severe hail will be possible on Monday afternoon to early evening across parts of the eastern Great Basin to Four Corners. ...Eastern Great Basin to the Four Corners... An amplified closed mid/upper low over northern/central CA at 12Z Monday should initially move east before curling northeast Monday night towards the NV/UT/ID border area. This will occur in response to a vigorous mid-level jet translating through the basal portion of the large-scale trough across the Desert Southwest into the eastern Great Basin. Surface cyclogenesis should be induced near the UT/NV border area, with a predominant meridional deep-layer flow regime near/just ahead of the low. Isolated to scattered thunderstorms should develop as modest steepening of mid-level lapse rates overspreads a deepening boundary layer during the afternoon. The strengthening synoptic flow regime coupled with inverted-v thermodynamic profiles west of the Wasatch Range may yield sporadic severe gusts with low-topped, high-based convection. Farther southeast towards the Four Corners, a more southwesterly mid to upper-flow regime should yield hodograph elongation, conditionally supporting splitting supercells. Warmer mid-level temperatures and correspondingly weaker lapse rates should temper parcel acceleration to an extent, but this may be offset by somewhat higher PW values. Marginally severe hail/gusts will be possible. ...Coastal Carolinas... Guidance has trended towards a greater signal for offshore subtropical or tropical cyclogenesis by Monday. Still, spread is quite large with the degree of amplification as NCEP guidance appears to be on the aggressive spectrum relative to non-NCEP models. With timing and spatial differences also large, will defer on a potential tornado threat highlight. ..Grams.. 09/14/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sat Sep 14 2024 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN TO FOUR CORNERS... ...SUMMARY... Isolated severe gusts and small to marginally severe hail will be possible on Monday afternoon to early evening across parts of the eastern Great Basin to Four Corners. ...Eastern Great Basin to the Four Corners... An amplified closed mid/upper low over northern/central CA at 12Z Monday should initially move east before curling northeast Monday night towards the NV/UT/ID border area. This will occur in response to a vigorous mid-level jet translating through the basal portion of the large-scale trough across the Desert Southwest into the eastern Great Basin. Surface cyclogenesis should be induced near the UT/NV border area, with a predominant meridional deep-layer flow regime near/just ahead of the low. Isolated to scattered thunderstorms should develop as modest steepening of mid-level lapse rates overspreads a deepening boundary layer during the afternoon. The strengthening synoptic flow regime coupled with inverted-v thermodynamic profiles west of the Wasatch Range may yield sporadic severe gusts with low-topped, high-based convection. Farther southeast towards the Four Corners, a more southwesterly mid to upper-flow regime should yield hodograph elongation, conditionally supporting splitting supercells. Warmer mid-level temperatures and correspondingly weaker lapse rates should temper parcel acceleration to an extent, but this may be offset by somewhat higher PW values. Marginally severe hail/gusts will be possible. ...Coastal Carolinas... Guidance has trended towards a greater signal for offshore subtropical or tropical cyclogenesis by Monday. Still, spread is quite large with the degree of amplification as NCEP guidance appears to be on the aggressive spectrum relative to non-NCEP models. With timing and spatial differences also large, will defer on a potential tornado threat highlight. ..Grams.. 09/14/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sat Sep 14 2024 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN TO FOUR CORNERS... ...SUMMARY... Isolated severe gusts and small to marginally severe hail will be possible on Monday afternoon to early evening across parts of the eastern Great Basin to Four Corners. ...Eastern Great Basin to the Four Corners... An amplified closed mid/upper low over northern/central CA at 12Z Monday should initially move east before curling northeast Monday night towards the NV/UT/ID border area. This will occur in response to a vigorous mid-level jet translating through the basal portion of the large-scale trough across the Desert Southwest into the eastern Great Basin. Surface cyclogenesis should be induced near the UT/NV border area, with a predominant meridional deep-layer flow regime near/just ahead of the low. Isolated to scattered thunderstorms should develop as modest steepening of mid-level lapse rates overspreads a deepening boundary layer during the afternoon. The strengthening synoptic flow regime coupled with inverted-v thermodynamic profiles west of the Wasatch Range may yield sporadic severe gusts with low-topped, high-based convection. Farther southeast towards the Four Corners, a more southwesterly mid to upper-flow regime should yield hodograph elongation, conditionally supporting splitting supercells. Warmer mid-level temperatures and correspondingly weaker lapse rates should temper parcel acceleration to an extent, but this may be offset by somewhat higher PW values. Marginally severe hail/gusts will be possible. ...Coastal Carolinas... Guidance has trended towards a greater signal for offshore subtropical or tropical cyclogenesis by Monday. Still, spread is quite large with the degree of amplification as NCEP guidance appears to be on the aggressive spectrum relative to non-NCEP models. With timing and spatial differences also large, will defer on a potential tornado threat highlight. ..Grams.. 09/14/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0145 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...Synopsis... Ahead of an amplifying large-scale trough over the West Coast, enhanced deep-layer meridional flow will overspread a diurnally deepening boundary layer (15-20 percent RH) over portions of the southern Great Basin. This, coupled with a tightening pressure gradient along the southern periphery of an evolving surface cyclone, will yield 20-25 mph sustained southerly surface winds. These winds will overlap the lowest RH over portions of southern NV, and given modestly receptive fuels here, elevated fire-weather conditions are expected. ..Weinman.. 09/14/2024 ...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 0145 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...Synopsis... Ahead of an amplifying large-scale trough over the West Coast, enhanced deep-layer meridional flow will overspread a diurnally deepening boundary layer (15-20 percent RH) over portions of the southern Great Basin. This, coupled with a tightening pressure gradient along the southern periphery of an evolving surface cyclone, will yield 20-25 mph sustained southerly surface winds. These winds will overlap the lowest RH over portions of southern NV, and given modestly receptive fuels here, elevated fire-weather conditions are expected. ..Weinman.. 09/14/2024 ...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 0145 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...Synopsis... Ahead of an amplifying large-scale trough over the West Coast, enhanced deep-layer meridional flow will overspread a diurnally deepening boundary layer (15-20 percent RH) over portions of the southern Great Basin. This, coupled with a tightening pressure gradient along the southern periphery of an evolving surface cyclone, will yield 20-25 mph sustained southerly surface winds. These winds will overlap the lowest RH over portions of southern NV, and given modestly receptive fuels here, elevated fire-weather conditions are expected. ..Weinman.. 09/14/2024 ...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 0145 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...Synopsis... Ahead of an amplifying large-scale trough over the West Coast, enhanced deep-layer meridional flow will overspread a diurnally deepening boundary layer (15-20 percent RH) over portions of the southern Great Basin. This, coupled with a tightening pressure gradient along the southern periphery of an evolving surface cyclone, will yield 20-25 mph sustained southerly surface winds. These winds will overlap the lowest RH over portions of southern NV, and given modestly receptive fuels here, elevated fire-weather conditions are expected. ..Weinman.. 09/14/2024 ...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 0145 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...Synopsis... Ahead of an amplifying large-scale trough over the West Coast, enhanced deep-layer meridional flow will overspread a diurnally deepening boundary layer (15-20 percent RH) over portions of the southern Great Basin. This, coupled with a tightening pressure gradient along the southern periphery of an evolving surface cyclone, will yield 20-25 mph sustained southerly surface winds. These winds will overlap the lowest RH over portions of southern NV, and given modestly receptive fuels here, elevated fire-weather conditions are expected. ..Weinman.. 09/14/2024 ...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 0144 AM CDT Sat Sep 14 2024 Valid 141200Z - 151200Z ...Synopsis... A midlevel jet streak will cross the northern Rockies today, encouraging lee troughing along the northern/central High Plains. Over portions of WY, 15-20 mph sustained west-southwesterly surface winds and 10-15 percent RH will develop in response to the lee troughing and deep boundary-layer mixing into the enhanced flow aloft. Given modestly receptive fuels across the area, elevated fire-weather conditions are expected during the afternoon. Farther west, breezy southerly surface winds are expected amid 15-20 percent RH across portions of the southern Great Basin -- within the base of a gradually amplifying large-scale trough. While locally elevated fire-weather conditions are possible, a lack of stronger sustained surface winds should limit the overall fire-weather risk. ..Weinman.. 09/14/2024 ...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 0144 AM CDT Sat Sep 14 2024 Valid 141200Z - 151200Z ...Synopsis... A midlevel jet streak will cross the northern Rockies today, encouraging lee troughing along the northern/central High Plains. Over portions of WY, 15-20 mph sustained west-southwesterly surface winds and 10-15 percent RH will develop in response to the lee troughing and deep boundary-layer mixing into the enhanced flow aloft. Given modestly receptive fuels across the area, elevated fire-weather conditions are expected during the afternoon. Farther west, breezy southerly surface winds are expected amid 15-20 percent RH across portions of the southern Great Basin -- within the base of a gradually amplifying large-scale trough. While locally elevated fire-weather conditions are possible, a lack of stronger sustained surface winds should limit the overall fire-weather risk. ..Weinman.. 09/14/2024 ...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 0144 AM CDT Sat Sep 14 2024 Valid 141200Z - 151200Z ...Synopsis... A midlevel jet streak will cross the northern Rockies today, encouraging lee troughing along the northern/central High Plains. Over portions of WY, 15-20 mph sustained west-southwesterly surface winds and 10-15 percent RH will develop in response to the lee troughing and deep boundary-layer mixing into the enhanced flow aloft. Given modestly receptive fuels across the area, elevated fire-weather conditions are expected during the afternoon. Farther west, breezy southerly surface winds are expected amid 15-20 percent RH across portions of the southern Great Basin -- within the base of a gradually amplifying large-scale trough. While locally elevated fire-weather conditions are possible, a lack of stronger sustained surface winds should limit the overall fire-weather risk. ..Weinman.. 09/14/2024 ...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 0144 AM CDT Sat Sep 14 2024 Valid 141200Z - 151200Z ...Synopsis... A midlevel jet streak will cross the northern Rockies today, encouraging lee troughing along the northern/central High Plains. Over portions of WY, 15-20 mph sustained west-southwesterly surface winds and 10-15 percent RH will develop in response to the lee troughing and deep boundary-layer mixing into the enhanced flow aloft. Given modestly receptive fuels across the area, elevated fire-weather conditions are expected during the afternoon. Farther west, breezy southerly surface winds are expected amid 15-20 percent RH across portions of the southern Great Basin -- within the base of a gradually amplifying large-scale trough. While locally elevated fire-weather conditions are possible, a lack of stronger sustained surface winds should limit the overall fire-weather risk. ..Weinman.. 09/14/2024 ...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 0144 AM CDT Sat Sep 14 2024 Valid 141200Z - 151200Z ...Synopsis... A midlevel jet streak will cross the northern Rockies today, encouraging lee troughing along the northern/central High Plains. Over portions of WY, 15-20 mph sustained west-southwesterly surface winds and 10-15 percent RH will develop in response to the lee troughing and deep boundary-layer mixing into the enhanced flow aloft. Given modestly receptive fuels across the area, elevated fire-weather conditions are expected during the afternoon. Farther west, breezy southerly surface winds are expected amid 15-20 percent RH across portions of the southern Great Basin -- within the base of a gradually amplifying large-scale trough. While locally elevated fire-weather conditions are possible, a lack of stronger sustained surface winds should limit the overall fire-weather risk. ..Weinman.. 09/14/2024 ...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 1244 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected Sunday. ...Discussion... A blocking upper pattern will hold in the East, with a stout mid-level anticyclone over the Lower Great Lakes and the remnants of post-TC Francine in the Lower MS Valley. A strong mid/upper jet approaching the Pacific Coast will yield a closed mid/upper low over northern to central CA by Sunday night. Strengthening large-scale ascent downstream should foster a broadening area of low-probability thunderstorm potential in the West amid scant buoyancy north of AZ. During the late afternoon, moderate MLCAPE should develop across parts of the western Great Plains to central TX. This could be sufficient for a few strong, but pulse-type thunderstorms given predominantly weak shear. ..Grams.. 09/14/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1244 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected Sunday. ...Discussion... A blocking upper pattern will hold in the East, with a stout mid-level anticyclone over the Lower Great Lakes and the remnants of post-TC Francine in the Lower MS Valley. A strong mid/upper jet approaching the Pacific Coast will yield a closed mid/upper low over northern to central CA by Sunday night. Strengthening large-scale ascent downstream should foster a broadening area of low-probability thunderstorm potential in the West amid scant buoyancy north of AZ. During the late afternoon, moderate MLCAPE should develop across parts of the western Great Plains to central TX. This could be sufficient for a few strong, but pulse-type thunderstorms given predominantly weak shear. ..Grams.. 09/14/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1244 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected Sunday. ...Discussion... A blocking upper pattern will hold in the East, with a stout mid-level anticyclone over the Lower Great Lakes and the remnants of post-TC Francine in the Lower MS Valley. A strong mid/upper jet approaching the Pacific Coast will yield a closed mid/upper low over northern to central CA by Sunday night. Strengthening large-scale ascent downstream should foster a broadening area of low-probability thunderstorm potential in the West amid scant buoyancy north of AZ. During the late afternoon, moderate MLCAPE should develop across parts of the western Great Plains to central TX. This could be sufficient for a few strong, but pulse-type thunderstorms given predominantly weak shear. ..Grams.. 09/14/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1244 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected Sunday. ...Discussion... A blocking upper pattern will hold in the East, with a stout mid-level anticyclone over the Lower Great Lakes and the remnants of post-TC Francine in the Lower MS Valley. A strong mid/upper jet approaching the Pacific Coast will yield a closed mid/upper low over northern to central CA by Sunday night. Strengthening large-scale ascent downstream should foster a broadening area of low-probability thunderstorm potential in the West amid scant buoyancy north of AZ. During the late afternoon, moderate MLCAPE should develop across parts of the western Great Plains to central TX. This could be sufficient for a few strong, but pulse-type thunderstorms given predominantly weak shear. ..Grams.. 09/14/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1244 AM CDT Sat Sep 14 2024 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected Sunday. ...Discussion... A blocking upper pattern will hold in the East, with a stout mid-level anticyclone over the Lower Great Lakes and the remnants of post-TC Francine in the Lower MS Valley. A strong mid/upper jet approaching the Pacific Coast will yield a closed mid/upper low over northern to central CA by Sunday night. Strengthening large-scale ascent downstream should foster a broadening area of low-probability thunderstorm potential in the West amid scant buoyancy north of AZ. During the late afternoon, moderate MLCAPE should develop across parts of the western Great Plains to central TX. This could be sufficient for a few strong, but pulse-type thunderstorms given predominantly weak shear. ..Grams.. 09/14/2024 Read more