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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 10 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms will be possible on Monday along parts of the eastern Gulf Coast, Atlantic Seaboard and in the western states. No severe threat is expected across the continental U.S. Monday or Monday night. ...DISCUSSION... A mid-level trough will move through the eastern U.S. on Monday, as a cold front advances southeastward into the Mid-Atlantic and southern Appalachians. Ahead of the front, thunderstorms will be possible on Monday within a moist airmass across the eastern Carolinas. Isolated storms may also occur along a sea breeze boundary in coastal parts of south and east Florida. In addition, some lighting strikes may occur in the central Gulf Coast, in association with the outer bands of Tropical Cyclone Rafael. In the western U.S., thunderstorms may develop on Monday ahead of a mid-level trough from the Sierras northward into western Oregon and western Washington. No severe threat is expected across the continental U.S. Monday and Monday night. ..Broyles.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1039 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED TO CHANGE SUNDAY TO MONDAY ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Monday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1016 AM CST Sun Nov 10 2024 Valid 101630Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Discussion... An upper low now crossing the Upper Mississippi Valley is forecast to gradually devolve into an open wave, as it crosses the Upper Great Lakes region and shifts across the Ottawa River and St. Lawrence Valleys, and Lower Great Lakes through the end of the period. As this occurs, a surface cold front will similarly progress eastward across the Upper Great Lakes and Midwest region today, reaching the central and southern Appalachians by 11/12Z (Sunday morning). Ahead of the front, a relatively moist boundary layer but weak lapse rates aloft will permit only weak warm-sector instability. While a more tropical low-level airmass will reside in the vicinity of the Lower Mississippi Valley, in part due to east-southeasterly advection associated with the presence of Tropical Storm Rafael sitting nearly stationary over the central Gulf, weak shear precludes appreciable severe potential. Farther north, stronger flow aloft will be offset by lower theta-e/weak CAPE as compared to areas farther south. As such, severe weather is not anticipated. ..Goss/Lyons.. 11/10/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...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 0929 AM CST Sun Nov 10 2024 Valid 101700Z - 111200Z Elevated conditions are likely from northern New Jersey and far northeast Pennsylvania to southern New England late this morning into the afternoon before showers arrive as a warm front lifts northward through the Northeast. Locally elevated conditions are already developing in parts of Upstate New York and northeast Pennsylvania ahead of the increasing cloud cover and showers. While marginally elevated conditions are expected in a relatively narrow temporal window, the ongoing drought and record high fire danger in the region led to the issuance. ..Nauslar.. 11/10/2024 .PREV DISCUSSION... /ISSUED 1218 AM CST Sun Nov 10 2024/ ...Synopsis... Fire weather concerns are expected to be minimal today across the CONUS. 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. Some briefly Elevated conditions are possible in the Northeast ahead of the approaching front, but wetting rainfall will be expected by the afternoon. Lingering dry conditions will be possible across southern California, but generally light winds will keep fire concerns low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0626 AM CST Sun Nov 10 2024 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Synopsis... General upper-air pattern deamplification is expected over most of the CONUS through the period, except over: 1. The West Coast (height falls ahead of an approaching, high-amplitude synoptic trough) and 2. The Great Lakes (height falls preceding the ejection of the cyclone now centered over northwest IA). The formerly cut-off/larger cyclone is rejoining the prevailing westerlies, and will accelerate eastward and weaken over the Great Lakes. This will happen as a strong shortwave trough -- evident in moisture-channel imagery over eastern/southern AB -- digs east-southeastward toward Lake Superior by 12Z tomorrow, while forming a closed or nearly closed 500-mb low. Meanwhile, Tropical Storm Rafael continues to weaken as its low- level center and deep convection get more displaced from each other, per NHC discussions. The circulation is forecast to continue weakening, as the low-level vortex loops around the central/west- central Gulf today, then shift southwestward thereafter. Refer to NHC advisories for latest forecast track/intensity of Rafael. In between those features, a plume of moist low-level air, cooling northward at the surface and aloft, will support isolated to scattered thunderstorms, near and east of an occluded/cold frontal zone drawn at 11Z from southern IL across westernmost portions of KY/TN, western MS, central/southwestern LA, and TX coastal waters. ...Gulf Coast to Ohio Valley... Overall severe potential will be limited by lack of stronger shear in the south (closer to the coast) where low-level theta-e is largest, and lack of surface-based instability in the north. Some model soundings suggest that surface-based parcels and marginal deep shear (effective-shear magnitudes in the 30-40-kt range) may overlap this afternoon over portions of the Tennessee Valley to lower Ohio Valley. While this will need to be monitored, lack of backing in low-level flow will limit both convergence and hodograph size, amid weak deep-layer lapse rates and potentially messy convective mode. At this time, the severe threat appears too low and conditional for an outlook area. ..Edwards/Bentley.. 11/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0626 AM CST Sun Nov 10 2024 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Synopsis... General upper-air pattern deamplification is expected over most of the CONUS through the period, except over: 1. The West Coast (height falls ahead of an approaching, high-amplitude synoptic trough) and 2. The Great Lakes (height falls preceding the ejection of the cyclone now centered over northwest IA). The formerly cut-off/larger cyclone is rejoining the prevailing westerlies, and will accelerate eastward and weaken over the Great Lakes. This will happen as a strong shortwave trough -- evident in moisture-channel imagery over eastern/southern AB -- digs east-southeastward toward Lake Superior by 12Z tomorrow, while forming a closed or nearly closed 500-mb low. Meanwhile, Tropical Storm Rafael continues to weaken as its low- level center and deep convection get more displaced from each other, per NHC discussions. The circulation is forecast to continue weakening, as the low-level vortex loops around the central/west- central Gulf today, then shift southwestward thereafter. Refer to NHC advisories for latest forecast track/intensity of Rafael. In between those features, a plume of moist low-level air, cooling northward at the surface and aloft, will support isolated to scattered thunderstorms, near and east of an occluded/cold frontal zone drawn at 11Z from southern IL across westernmost portions of KY/TN, western MS, central/southwestern LA, and TX coastal waters. ...Gulf Coast to Ohio Valley... Overall severe potential will be limited by lack of stronger shear in the south (closer to the coast) where low-level theta-e is largest, and lack of surface-based instability in the north. Some model soundings suggest that surface-based parcels and marginal deep shear (effective-shear magnitudes in the 30-40-kt range) may overlap this afternoon over portions of the Tennessee Valley to lower Ohio Valley. While this will need to be monitored, lack of backing in low-level flow will limit both convergence and hodograph size, amid weak deep-layer lapse rates and potentially messy convective mode. At this time, the severe threat appears too low and conditional for an outlook area. ..Edwards/Bentley.. 11/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0626 AM CST Sun Nov 10 2024 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Synopsis... General upper-air pattern deamplification is expected over most of the CONUS through the period, except over: 1. The West Coast (height falls ahead of an approaching, high-amplitude synoptic trough) and 2. The Great Lakes (height falls preceding the ejection of the cyclone now centered over northwest IA). The formerly cut-off/larger cyclone is rejoining the prevailing westerlies, and will accelerate eastward and weaken over the Great Lakes. This will happen as a strong shortwave trough -- evident in moisture-channel imagery over eastern/southern AB -- digs east-southeastward toward Lake Superior by 12Z tomorrow, while forming a closed or nearly closed 500-mb low. Meanwhile, Tropical Storm Rafael continues to weaken as its low- level center and deep convection get more displaced from each other, per NHC discussions. The circulation is forecast to continue weakening, as the low-level vortex loops around the central/west- central Gulf today, then shift southwestward thereafter. Refer to NHC advisories for latest forecast track/intensity of Rafael. In between those features, a plume of moist low-level air, cooling northward at the surface and aloft, will support isolated to scattered thunderstorms, near and east of an occluded/cold frontal zone drawn at 11Z from southern IL across westernmost portions of KY/TN, western MS, central/southwestern LA, and TX coastal waters. ...Gulf Coast to Ohio Valley... Overall severe potential will be limited by lack of stronger shear in the south (closer to the coast) where low-level theta-e is largest, and lack of surface-based instability in the north. Some model soundings suggest that surface-based parcels and marginal deep shear (effective-shear magnitudes in the 30-40-kt range) may overlap this afternoon over portions of the Tennessee Valley to lower Ohio Valley. While this will need to be monitored, lack of backing in low-level flow will limit both convergence and hodograph size, amid weak deep-layer lapse rates and potentially messy convective mode. At this time, the severe threat appears too low and conditional for an outlook area. ..Edwards/Bentley.. 11/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0626 AM CST Sun Nov 10 2024 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Synopsis... General upper-air pattern deamplification is expected over most of the CONUS through the period, except over: 1. The West Coast (height falls ahead of an approaching, high-amplitude synoptic trough) and 2. The Great Lakes (height falls preceding the ejection of the cyclone now centered over northwest IA). The formerly cut-off/larger cyclone is rejoining the prevailing westerlies, and will accelerate eastward and weaken over the Great Lakes. This will happen as a strong shortwave trough -- evident in moisture-channel imagery over eastern/southern AB -- digs east-southeastward toward Lake Superior by 12Z tomorrow, while forming a closed or nearly closed 500-mb low. Meanwhile, Tropical Storm Rafael continues to weaken as its low- level center and deep convection get more displaced from each other, per NHC discussions. The circulation is forecast to continue weakening, as the low-level vortex loops around the central/west- central Gulf today, then shift southwestward thereafter. Refer to NHC advisories for latest forecast track/intensity of Rafael. In between those features, a plume of moist low-level air, cooling northward at the surface and aloft, will support isolated to scattered thunderstorms, near and east of an occluded/cold frontal zone drawn at 11Z from southern IL across westernmost portions of KY/TN, western MS, central/southwestern LA, and TX coastal waters. ...Gulf Coast to Ohio Valley... Overall severe potential will be limited by lack of stronger shear in the south (closer to the coast) where low-level theta-e is largest, and lack of surface-based instability in the north. Some model soundings suggest that surface-based parcels and marginal deep shear (effective-shear magnitudes in the 30-40-kt range) may overlap this afternoon over portions of the Tennessee Valley to lower Ohio Valley. While this will need to be monitored, lack of backing in low-level flow will limit both convergence and hodograph size, amid weak deep-layer lapse rates and potentially messy convective mode. At this time, the severe threat appears too low and conditional for an outlook area. ..Edwards/Bentley.. 11/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0626 AM CST Sun Nov 10 2024 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears minimal through tonight. ...Synopsis... General upper-air pattern deamplification is expected over most of the CONUS through the period, except over: 1. The West Coast (height falls ahead of an approaching, high-amplitude synoptic trough) and 2. The Great Lakes (height falls preceding the ejection of the cyclone now centered over northwest IA). The formerly cut-off/larger cyclone is rejoining the prevailing westerlies, and will accelerate eastward and weaken over the Great Lakes. This will happen as a strong shortwave trough -- evident in moisture-channel imagery over eastern/southern AB -- digs east-southeastward toward Lake Superior by 12Z tomorrow, while forming a closed or nearly closed 500-mb low. Meanwhile, Tropical Storm Rafael continues to weaken as its low- level center and deep convection get more displaced from each other, per NHC discussions. The circulation is forecast to continue weakening, as the low-level vortex loops around the central/west- central Gulf today, then shift southwestward thereafter. Refer to NHC advisories for latest forecast track/intensity of Rafael. In between those features, a plume of moist low-level air, cooling northward at the surface and aloft, will support isolated to scattered thunderstorms, near and east of an occluded/cold frontal zone drawn at 11Z from southern IL across westernmost portions of KY/TN, western MS, central/southwestern LA, and TX coastal waters. ...Gulf Coast to Ohio Valley... Overall severe potential will be limited by lack of stronger shear in the south (closer to the coast) where low-level theta-e is largest, and lack of surface-based instability in the north. Some model soundings suggest that surface-based parcels and marginal deep shear (effective-shear magnitudes in the 30-40-kt range) may overlap this afternoon over portions of the Tennessee Valley to lower Ohio Valley. While this will need to be monitored, lack of backing in low-level flow will limit both convergence and hodograph size, amid weak deep-layer lapse rates and potentially messy convective mode. At this time, the severe threat appears too low and conditional for an outlook area. ..Edwards/Bentley.. 11/10/2024 Read more