Severe Storms

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0205 AM CDT Mon Sep 23 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is uncertain, but limited, on Wednesday. ...Southeast into the central Appalachians... Forecast uncertainty is quite high for Day 3/Wed. The evolution of the upper trough over the Upper Midwest/MS Valley early in the day is varied across forecast guidance. A northern stream upper shortwave trough will probably migrate across the Great Lakes. The southern stream of this trough may develop a closed low over the Mid-South into the lower OH/TN Valley vicinity. Meanwhile, the tropical disturbance currently over the western Caribbean is likely to develop into a tropical cyclone by Wednesday per latest NHC guidance. The track of this feature is also uncertain and will be influenced by the evolution of the aforementioned upper trough. Some tropical cyclone related tornado risk could develop across the west coast of FL, but given the high degree of uncertainty at this time, will hold off on introducing a Marginal risk. Otherwise, a moist warm sector will exist across much of the Gulf coast states into parts oft he central Appalachians as moderate deep-layer south/southwesterly flow streams over the region. Precipitation will likely be ongoing Wednesday morning, resulting in uncertainty in daytime destabilization across the region. Some low-end severe thunderstorm potential may evolve, but uncertainty is too great to include probabilities at this time. ..Leitman.. 09/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0205 AM CDT Mon Sep 23 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is uncertain, but limited, on Wednesday. ...Southeast into the central Appalachians... Forecast uncertainty is quite high for Day 3/Wed. The evolution of the upper trough over the Upper Midwest/MS Valley early in the day is varied across forecast guidance. A northern stream upper shortwave trough will probably migrate across the Great Lakes. The southern stream of this trough may develop a closed low over the Mid-South into the lower OH/TN Valley vicinity. Meanwhile, the tropical disturbance currently over the western Caribbean is likely to develop into a tropical cyclone by Wednesday per latest NHC guidance. The track of this feature is also uncertain and will be influenced by the evolution of the aforementioned upper trough. Some tropical cyclone related tornado risk could develop across the west coast of FL, but given the high degree of uncertainty at this time, will hold off on introducing a Marginal risk. Otherwise, a moist warm sector will exist across much of the Gulf coast states into parts oft he central Appalachians as moderate deep-layer south/southwesterly flow streams over the region. Precipitation will likely be ongoing Wednesday morning, resulting in uncertainty in daytime destabilization across the region. Some low-end severe thunderstorm potential may evolve, but uncertainty is too great to include probabilities at this time. ..Leitman.. 09/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0205 AM CDT Mon Sep 23 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is uncertain, but limited, on Wednesday. ...Southeast into the central Appalachians... Forecast uncertainty is quite high for Day 3/Wed. The evolution of the upper trough over the Upper Midwest/MS Valley early in the day is varied across forecast guidance. A northern stream upper shortwave trough will probably migrate across the Great Lakes. The southern stream of this trough may develop a closed low over the Mid-South into the lower OH/TN Valley vicinity. Meanwhile, the tropical disturbance currently over the western Caribbean is likely to develop into a tropical cyclone by Wednesday per latest NHC guidance. The track of this feature is also uncertain and will be influenced by the evolution of the aforementioned upper trough. Some tropical cyclone related tornado risk could develop across the west coast of FL, but given the high degree of uncertainty at this time, will hold off on introducing a Marginal risk. Otherwise, a moist warm sector will exist across much of the Gulf coast states into parts oft he central Appalachians as moderate deep-layer south/southwesterly flow streams over the region. Precipitation will likely be ongoing Wednesday morning, resulting in uncertainty in daytime destabilization across the region. Some low-end severe thunderstorm potential may evolve, but uncertainty is too great to include probabilities at this time. ..Leitman.. 09/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0205 AM CDT Mon Sep 23 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is uncertain, but limited, on Wednesday. ...Southeast into the central Appalachians... Forecast uncertainty is quite high for Day 3/Wed. The evolution of the upper trough over the Upper Midwest/MS Valley early in the day is varied across forecast guidance. A northern stream upper shortwave trough will probably migrate across the Great Lakes. The southern stream of this trough may develop a closed low over the Mid-South into the lower OH/TN Valley vicinity. Meanwhile, the tropical disturbance currently over the western Caribbean is likely to develop into a tropical cyclone by Wednesday per latest NHC guidance. The track of this feature is also uncertain and will be influenced by the evolution of the aforementioned upper trough. Some tropical cyclone related tornado risk could develop across the west coast of FL, but given the high degree of uncertainty at this time, will hold off on introducing a Marginal risk. Otherwise, a moist warm sector will exist across much of the Gulf coast states into parts oft he central Appalachians as moderate deep-layer south/southwesterly flow streams over the region. Precipitation will likely be ongoing Wednesday morning, resulting in uncertainty in daytime destabilization across the region. Some low-end severe thunderstorm potential may evolve, but uncertainty is too great to include probabilities at this time. ..Leitman.. 09/23/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will remain low on Tuesday across the CONUS. A ridge will build in across the western US, with dry and warming conditions amid generally light winds. Longwave troughing will deepen across the Plains, with some post-frontal northwesterly breezes across the High Plains. Overall, cool conditions will keep relative humidity values high and there is potential for wetting rainfall Monday into Tuesday. ..Thornton.. 09/23/2024 ...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 0148 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will remain low on Tuesday across the CONUS. A ridge will build in across the western US, with dry and warming conditions amid generally light winds. Longwave troughing will deepen across the Plains, with some post-frontal northwesterly breezes across the High Plains. Overall, cool conditions will keep relative humidity values high and there is potential for wetting rainfall Monday into Tuesday. ..Thornton.. 09/23/2024 ...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 0148 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will remain low on Tuesday across the CONUS. A ridge will build in across the western US, with dry and warming conditions amid generally light winds. Longwave troughing will deepen across the Plains, with some post-frontal northwesterly breezes across the High Plains. Overall, cool conditions will keep relative humidity values high and there is potential for wetting rainfall Monday into Tuesday. ..Thornton.. 09/23/2024 ...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 0148 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will remain low on Tuesday across the CONUS. A ridge will build in across the western US, with dry and warming conditions amid generally light winds. Longwave troughing will deepen across the Plains, with some post-frontal northwesterly breezes across the High Plains. Overall, cool conditions will keep relative humidity values high and there is potential for wetting rainfall Monday into Tuesday. ..Thornton.. 09/23/2024 ...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 0147 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low today across the CONUS. Across the central US, cool and wet conditions continue beneath mid-level troughing. Ridging will begin building across the western US with warming conditions. Dry conditions are expected across the southwest, but generally light winds will keep fire concerns low. ..Thornton.. 09/23/2024 ...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 0147 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low today across the CONUS. Across the central US, cool and wet conditions continue beneath mid-level troughing. Ridging will begin building across the western US with warming conditions. Dry conditions are expected across the southwest, but generally light winds will keep fire concerns low. ..Thornton.. 09/23/2024 ...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 0147 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low today across the CONUS. Across the central US, cool and wet conditions continue beneath mid-level troughing. Ridging will begin building across the western US with warming conditions. Dry conditions are expected across the southwest, but generally light winds will keep fire concerns low. ..Thornton.. 09/23/2024 ...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 0147 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low today across the CONUS. Across the central US, cool and wet conditions continue beneath mid-level troughing. Ridging will begin building across the western US with warming conditions. Dry conditions are expected across the southwest, but generally light winds will keep fire concerns low. ..Thornton.. 09/23/2024 ...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 1228 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS TOWARD THE CENTRAL/SOUTHERN APPALACHIANS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. ...OH/TN Valleys toward the Central/Southern Appalachians... A complicated/messy scenario is unfolding for severe potential on Tuesday. Most 00z CAMs and deterministic guidance suggests potentially widespread convection may be ongoing Tuesday morning across the Ohio Valley vicinity. This will limit heating and destabilization across a broad warm sector ahead of an eastward-advancing surface cold front. Nevertheless, a deepening mid/upper trough will slowly shift east from eastern portions of the central/southern Plains toward the MS River. Strengthening deep-layer southwesterly flow will overspread the region, providing support for organized convection, with a mix clusters and line segments possible. Given uncertainty due to morning convection and subsequent airmass destabilization, as well has some disagreement in timing of the mid/upper trough, have introduced a rather broad Marginal risk (level 1 of 5). Some refinement of this area, and/or potential upgrades may be needed in subsequent outlooks if confidence sufficiently increases in a more favorable/focused corridor of severe potential. Where stronger heating/destabilization can occur, damaging gusts will be possible. ..Leitman.. 09/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS TOWARD THE CENTRAL/SOUTHERN APPALACHIANS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. ...OH/TN Valleys toward the Central/Southern Appalachians... A complicated/messy scenario is unfolding for severe potential on Tuesday. Most 00z CAMs and deterministic guidance suggests potentially widespread convection may be ongoing Tuesday morning across the Ohio Valley vicinity. This will limit heating and destabilization across a broad warm sector ahead of an eastward-advancing surface cold front. Nevertheless, a deepening mid/upper trough will slowly shift east from eastern portions of the central/southern Plains toward the MS River. Strengthening deep-layer southwesterly flow will overspread the region, providing support for organized convection, with a mix clusters and line segments possible. Given uncertainty due to morning convection and subsequent airmass destabilization, as well has some disagreement in timing of the mid/upper trough, have introduced a rather broad Marginal risk (level 1 of 5). Some refinement of this area, and/or potential upgrades may be needed in subsequent outlooks if confidence sufficiently increases in a more favorable/focused corridor of severe potential. Where stronger heating/destabilization can occur, damaging gusts will be possible. ..Leitman.. 09/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS TOWARD THE CENTRAL/SOUTHERN APPALACHIANS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. ...OH/TN Valleys toward the Central/Southern Appalachians... A complicated/messy scenario is unfolding for severe potential on Tuesday. Most 00z CAMs and deterministic guidance suggests potentially widespread convection may be ongoing Tuesday morning across the Ohio Valley vicinity. This will limit heating and destabilization across a broad warm sector ahead of an eastward-advancing surface cold front. Nevertheless, a deepening mid/upper trough will slowly shift east from eastern portions of the central/southern Plains toward the MS River. Strengthening deep-layer southwesterly flow will overspread the region, providing support for organized convection, with a mix clusters and line segments possible. Given uncertainty due to morning convection and subsequent airmass destabilization, as well has some disagreement in timing of the mid/upper trough, have introduced a rather broad Marginal risk (level 1 of 5). Some refinement of this area, and/or potential upgrades may be needed in subsequent outlooks if confidence sufficiently increases in a more favorable/focused corridor of severe potential. Where stronger heating/destabilization can occur, damaging gusts will be possible. ..Leitman.. 09/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS TOWARD THE CENTRAL/SOUTHERN APPALACHIANS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. ...OH/TN Valleys toward the Central/Southern Appalachians... A complicated/messy scenario is unfolding for severe potential on Tuesday. Most 00z CAMs and deterministic guidance suggests potentially widespread convection may be ongoing Tuesday morning across the Ohio Valley vicinity. This will limit heating and destabilization across a broad warm sector ahead of an eastward-advancing surface cold front. Nevertheless, a deepening mid/upper trough will slowly shift east from eastern portions of the central/southern Plains toward the MS River. Strengthening deep-layer southwesterly flow will overspread the region, providing support for organized convection, with a mix clusters and line segments possible. Given uncertainty due to morning convection and subsequent airmass destabilization, as well has some disagreement in timing of the mid/upper trough, have introduced a rather broad Marginal risk (level 1 of 5). Some refinement of this area, and/or potential upgrades may be needed in subsequent outlooks if confidence sufficiently increases in a more favorable/focused corridor of severe potential. Where stronger heating/destabilization can occur, damaging gusts will be possible. ..Leitman.. 09/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Mon Sep 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO AND TENNESSEE VALLEYS TOWARD THE CENTRAL/SOUTHERN APPALACHIANS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. ...OH/TN Valleys toward the Central/Southern Appalachians... A complicated/messy scenario is unfolding for severe potential on Tuesday. Most 00z CAMs and deterministic guidance suggests potentially widespread convection may be ongoing Tuesday morning across the Ohio Valley vicinity. This will limit heating and destabilization across a broad warm sector ahead of an eastward-advancing surface cold front. Nevertheless, a deepening mid/upper trough will slowly shift east from eastern portions of the central/southern Plains toward the MS River. Strengthening deep-layer southwesterly flow will overspread the region, providing support for organized convection, with a mix clusters and line segments possible. Given uncertainty due to morning convection and subsequent airmass destabilization, as well has some disagreement in timing of the mid/upper trough, have introduced a rather broad Marginal risk (level 1 of 5). Some refinement of this area, and/or potential upgrades may be needed in subsequent outlooks if confidence sufficiently increases in a more favorable/focused corridor of severe potential. Where stronger heating/destabilization can occur, damaging gusts will be possible. ..Leitman.. 09/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1223 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE OZARKS TO THE OHIO/TENNESSEE VALLEYS REGION... ...SUMMARY... Isolated strong to severe thunderstorms are possible from the Ozarks into parts of the Tennessee and lower Ohio Valleys. ...Ozarks to TN/OH Valley Region... Northern-stream short-wave trough is forecast to dig into the northern Plains later this afternoon, which will encourage the positive-tilt trough over the central Plains to eject east, and deamplify over the MS Valley late in the period. This evolution is expected to aid weak surface wave/low development along the synoptic front, mostly likely over northern AR early in the period. Latest model guidance suggests this weak feature will track northeast into southern IN by 24/12z. While the surface front is not particularly sharp, this boundary will serve as the focus for scattered convection through the period. Pre frontal boundary-layer heating will prove instrumental in destabilization as mid-level lapse rates should remain weak through the period. Latest NAM suggests 0-3km lapse rates will steepen across eastern AR into western KY by early afternoon, which will result in MLCAPE in excess of 1000 J/kg, coincident with modest 0-6km bulk shear. Forecast soundings favor multi cell updrafts with some organizational potential, as effective shear will be on the order of 30kt along this pre frontal corridor. At this time it appears most updrafts will struggle to generate more than marginally strong gusts, or perhaps some hail approaching 1 inch. Most robust updrafts should develop by late morning and continue into the early-evening hours before nocturnal cooling lessens buoyancy. ..Darrow/Thornton.. 09/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1223 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE OZARKS TO THE OHIO/TENNESSEE VALLEYS REGION... ...SUMMARY... Isolated strong to severe thunderstorms are possible from the Ozarks into parts of the Tennessee and lower Ohio Valleys. ...Ozarks to TN/OH Valley Region... Northern-stream short-wave trough is forecast to dig into the northern Plains later this afternoon, which will encourage the positive-tilt trough over the central Plains to eject east, and deamplify over the MS Valley late in the period. This evolution is expected to aid weak surface wave/low development along the synoptic front, mostly likely over northern AR early in the period. Latest model guidance suggests this weak feature will track northeast into southern IN by 24/12z. While the surface front is not particularly sharp, this boundary will serve as the focus for scattered convection through the period. Pre frontal boundary-layer heating will prove instrumental in destabilization as mid-level lapse rates should remain weak through the period. Latest NAM suggests 0-3km lapse rates will steepen across eastern AR into western KY by early afternoon, which will result in MLCAPE in excess of 1000 J/kg, coincident with modest 0-6km bulk shear. Forecast soundings favor multi cell updrafts with some organizational potential, as effective shear will be on the order of 30kt along this pre frontal corridor. At this time it appears most updrafts will struggle to generate more than marginally strong gusts, or perhaps some hail approaching 1 inch. Most robust updrafts should develop by late morning and continue into the early-evening hours before nocturnal cooling lessens buoyancy. ..Darrow/Thornton.. 09/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1223 AM CDT Mon Sep 23 2024 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE OZARKS TO THE OHIO/TENNESSEE VALLEYS REGION... ...SUMMARY... Isolated strong to severe thunderstorms are possible from the Ozarks into parts of the Tennessee and lower Ohio Valleys. ...Ozarks to TN/OH Valley Region... Northern-stream short-wave trough is forecast to dig into the northern Plains later this afternoon, which will encourage the positive-tilt trough over the central Plains to eject east, and deamplify over the MS Valley late in the period. This evolution is expected to aid weak surface wave/low development along the synoptic front, mostly likely over northern AR early in the period. Latest model guidance suggests this weak feature will track northeast into southern IN by 24/12z. While the surface front is not particularly sharp, this boundary will serve as the focus for scattered convection through the period. Pre frontal boundary-layer heating will prove instrumental in destabilization as mid-level lapse rates should remain weak through the period. Latest NAM suggests 0-3km lapse rates will steepen across eastern AR into western KY by early afternoon, which will result in MLCAPE in excess of 1000 J/kg, coincident with modest 0-6km bulk shear. Forecast soundings favor multi cell updrafts with some organizational potential, as effective shear will be on the order of 30kt along this pre frontal corridor. At this time it appears most updrafts will struggle to generate more than marginally strong gusts, or perhaps some hail approaching 1 inch. Most robust updrafts should develop by late morning and continue into the early-evening hours before nocturnal cooling lessens buoyancy. ..Darrow/Thornton.. 09/23/2024 Read more