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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0624 AM CST Sat Nov 09 2024 Valid 091300Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected over the conterminous U.S. through tonight. ...Synopsis/Discussion... The mid/upper-level pattern across the CONUS will lose amplitude through the period, as a synoptic-scale cyclone now centered near GLD weakens, ejects northeastward, and rejoins the prevailing westerlies. The associated 500-mb low should reach central NE by 00Z, then across northwestern IA by 12Z tomorrow. Meanwhile, the NHC forecasts Hurricane Rafael to move slowly west-northwest across the west-central Gulf through tonight, remaining far from land, while weakening due to deep shear and dry-air involvement. In between, a plume of partly modified return-flow air, marginally moist/unstable for deep convection, will support isolated to widely scattered thunderstorms in a broad swath from the TX/LA Gulf Coast to parts of IA/IN and much of IL. Effective inflow to convection in this swath should be elevated over the mid Mississippi Valley and similar latitudes, where deep shear is greatest. As shear weakens with southward extent from the Mid-South to the coast, especially south of a warm front now over north-central LA, surface-based parcels amid weak lapse rates will prevail. By afternoon, the warm front will angle northward into parts of eastern AR, and MLCAPE should range from around 500 J/kg over the Mid-South to near 1000 J/kg just inland from the coast. Organized severe potential will be stunted by lack of stronger lift and shear where buoyancy is sufficient. ..Edwards/Bentley.. 11/09/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CST Sat Nov 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... Guidance agreement has increased with regard to poor-quality moisture return ahead of an upper trough ejecting from the West into the central states on D4-5/Tuesday-Wednesday. A preceding surface ridge into the Gulf Coast region appears likely to inhibit appreciable poleward advection of Gulf moisture through D5. While differences remain in the evolution of the upper trough, guidance has markedly shifted north with cyclogenesis centered on the northern Great Plains. This setup appears unlikely to support an organized severe threat. Late week, the next broad upper trough has above-average agreement in reaching the West Coast. Guidance indicates potentially greater low-level moisture return from the western Gulf into the southern Great Plains. This suggests at least a low-probability severe threat may occur next weekend, as indicated by both SPC and NSSL GEFS-based ML guidance, which appears supported by the 00Z ECMWF ensemble mean. Predictability is low with the evolution of embedded shortwave impulse within this large-scale trough. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Sat Nov 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Monday or Monday night. ...Southeast... Thunderstorm potential should be focused during the first half of the period. A weak cold front will accelerate southeast as a surface anticyclone moves into the Upper Midwest and a ridge builds south across the MS Valley. Convergence along the front will remain weak within a predominately zonal flow regime. In conjunction, with persistent weakness in lapse rates above the boundary layer, thunderstorm coverage should tend to be isolated. ...Pacific Northwest... A leading shortwave trough and attendant surface cold front should move onshore Monday morning. In its wake, a generally onshore flow regime will persist through the period. Low to mid-level lapse rates will be steep, yielding instability amid meager buoyancy. An upstream shortwave impulse should aid in scattered, low-topped convection. Some of this will be sufficiently deep to foster sporadic lightning. Very isolated thunderstorms may occur farther inland towards the northern Great Basin. But confidence is low in whether scant buoyancy will develop east of the Cascade Range. ..Grams.. 11/09/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1233 AM CST Sat Nov 09 2024 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be low on Sunday. A trough will traverse the Great Lakes region, with cooler and wetter conditions extending from the Upper Midwest into the Ohio River Valley and up to the Northeast. Cooler post-frontal conditions will extend across much of the Plains. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ..Thornton.. 11/09/2024 ...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 1233 AM CST Sat Nov 09 2024 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be low on Sunday. A trough will traverse the Great Lakes region, with cooler and wetter conditions extending from the Upper Midwest into the Ohio River Valley and up to the Northeast. Cooler post-frontal conditions will extend across much of the Plains. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ..Thornton.. 11/09/2024 ...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 1233 AM CST Sat Nov 09 2024 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be low on Sunday. A trough will traverse the Great Lakes region, with cooler and wetter conditions extending from the Upper Midwest into the Ohio River Valley and up to the Northeast. Cooler post-frontal conditions will extend across much of the Plains. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ..Thornton.. 11/09/2024 ...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 1233 AM CST Sat Nov 09 2024 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be low on Sunday. A trough will traverse the Great Lakes region, with cooler and wetter conditions extending from the Upper Midwest into the Ohio River Valley and up to the Northeast. Cooler post-frontal conditions will extend across much of the Plains. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ..Thornton.. 11/09/2024 ...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 1233 AM CST Sat Nov 09 2024 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be low on Sunday. A trough will traverse the Great Lakes region, with cooler and wetter conditions extending from the Upper Midwest into the Ohio River Valley and up to the Northeast. Cooler post-frontal conditions will extend across much of the Plains. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ..Thornton.. 11/09/2024 ...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 1224 AM CST Sat Nov 09 2024 Valid 091200Z - 101200Z ...Synopsis... Fire weather concerns will be minimal across the CONUS today. A deepening trough will bring widespread rain across much of the central/southern Plains. Elsewhere, dry conditions will continue across southern California and across portions of New England. A small region of Elevated fire weather conditions will be possible across portions of coastal southern New England where gusts of 15 mph with RH below 30%. Winds across southern California are expected to be mainly light, precluding the need for inclusion of any areas. ..Thornton.. 11/09/2024 ...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 1224 AM CST Sat Nov 09 2024 Valid 091200Z - 101200Z ...Synopsis... Fire weather concerns will be minimal across the CONUS today. A deepening trough will bring widespread rain across much of the central/southern Plains. Elsewhere, dry conditions will continue across southern California and across portions of New England. A small region of Elevated fire weather conditions will be possible across portions of coastal southern New England where gusts of 15 mph with RH below 30%. Winds across southern California are expected to be mainly light, precluding the need for inclusion of any areas. ..Thornton.. 11/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more