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SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHEAST/CAROLINAS... ...SUMMARY... Scattered strong to potentially severe thunderstorms are possible Thursday across parts of the Southeast and Carolinas, with the greatest threat currently expected from late morning into the afternoon. Locally damaging wind, isolated hail, and a tornado or two are all possible. ...Synopsis... A large-scale mid/upper-level trough is forecast to amplify across the eastern CONUS on Thanksgiving Day. Within the larger trough, one shortwave will take on a negative tilt as it moves quickly east-northeastward from the OH/TN Valley region toward the Mid Atlantic and New England. In the wake of this leading shortwave trough, a northern-stream shortwave will move southeastward from the northern Great Plains toward the Ohio Valley by the end of the period. A surface cyclone associated with the leading shortwave will deepen as it moves from the Mid Atlantic toward southern New England and eventually the Canadian Maritimes. A trailing cold front will move across parts of the Carolinas/Virginia and the Southeast. ...Southeast into the Carolinas... Given the inconsistent signal for robust storm development, a Marginal Risk was maintained with this outlook. However, greater probabilities for all hazards may be needed if confidence increases regarding a sufficient coverage of organized storms through the day. Strong deep-layer flow/shear (with 60-80 kt flow at 500 mb) will be in place atop the relatively moist boundary layer across parts of the Southeast/Carolinas, prior to the frontal passage. Prefrontal MLCAPE is expected to generally be in the 500-1000 J/kg range, with higher values possible where stronger diurnal heating occurs. The resulting environment will be conditionally favorable for organized convection due to the strong deep-layer shear and sufficient instability. However, some weakening and veering of low-level flow is expected with time, as the primary cyclone and stronger large-scale ascent move quickly northeastward away from the region. As a result, uncertainty remains regarding the coverage and intensity of storms along/ahead of the front. Thunderstorms may develop or be ongoing during the morning, though the coverage and intensity of early-day convection remains unclear. Gradual intensification of ongoing convection and/or additional storm development will be possible with time, both along the front, and potentially in the warm sector if sufficient heating can remove any lingering MLCINH. The relatively modest large-scale ascent may limit storm coverage, but also potentially allow for a discrete or clustered supercell mode with the storms that do form. Any sustained supercells could pose an all-hazards severe threat, especially from GA into the Carolinas, where stronger low-level flow/shear may persist through the morning into at least the early afternoon, to the south of the surface low track. The 00Z HRRR/FV3 depict potential supercell development along/ahead of the front, but other 00Z HREF members show only minimal to very isolated organized storm development. Other guidance has generally trended toward a faster frontal passage (as depicted by the ECMWF/UKMET), which could be less favorable for organized storm potential due to reduced time for diurnal destabilization. Additional trimming of the Marginal Risk from the north may be needed if the trend toward a faster frontal passage continues. ..Dean.. 11/27/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHEAST/CAROLINAS... ...SUMMARY... Scattered strong to potentially severe thunderstorms are possible Thursday across parts of the Southeast and Carolinas, with the greatest threat currently expected from late morning into the afternoon. Locally damaging wind, isolated hail, and a tornado or two are all possible. ...Synopsis... A large-scale mid/upper-level trough is forecast to amplify across the eastern CONUS on Thanksgiving Day. Within the larger trough, one shortwave will take on a negative tilt as it moves quickly east-northeastward from the OH/TN Valley region toward the Mid Atlantic and New England. In the wake of this leading shortwave trough, a northern-stream shortwave will move southeastward from the northern Great Plains toward the Ohio Valley by the end of the period. A surface cyclone associated with the leading shortwave will deepen as it moves from the Mid Atlantic toward southern New England and eventually the Canadian Maritimes. A trailing cold front will move across parts of the Carolinas/Virginia and the Southeast. ...Southeast into the Carolinas... Given the inconsistent signal for robust storm development, a Marginal Risk was maintained with this outlook. However, greater probabilities for all hazards may be needed if confidence increases regarding a sufficient coverage of organized storms through the day. Strong deep-layer flow/shear (with 60-80 kt flow at 500 mb) will be in place atop the relatively moist boundary layer across parts of the Southeast/Carolinas, prior to the frontal passage. Prefrontal MLCAPE is expected to generally be in the 500-1000 J/kg range, with higher values possible where stronger diurnal heating occurs. The resulting environment will be conditionally favorable for organized convection due to the strong deep-layer shear and sufficient instability. However, some weakening and veering of low-level flow is expected with time, as the primary cyclone and stronger large-scale ascent move quickly northeastward away from the region. As a result, uncertainty remains regarding the coverage and intensity of storms along/ahead of the front. Thunderstorms may develop or be ongoing during the morning, though the coverage and intensity of early-day convection remains unclear. Gradual intensification of ongoing convection and/or additional storm development will be possible with time, both along the front, and potentially in the warm sector if sufficient heating can remove any lingering MLCINH. The relatively modest large-scale ascent may limit storm coverage, but also potentially allow for a discrete or clustered supercell mode with the storms that do form. Any sustained supercells could pose an all-hazards severe threat, especially from GA into the Carolinas, where stronger low-level flow/shear may persist through the morning into at least the early afternoon, to the south of the surface low track. The 00Z HRRR/FV3 depict potential supercell development along/ahead of the front, but other 00Z HREF members show only minimal to very isolated organized storm development. Other guidance has generally trended toward a faster frontal passage (as depicted by the ECMWF/UKMET), which could be less favorable for organized storm potential due to reduced time for diurnal destabilization. Additional trimming of the Marginal Risk from the north may be needed if the trend toward a faster frontal passage continues. ..Dean.. 11/27/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHEAST/CAROLINAS... ...SUMMARY... Scattered strong to potentially severe thunderstorms are possible Thursday across parts of the Southeast and Carolinas, with the greatest threat currently expected from late morning into the afternoon. Locally damaging wind, isolated hail, and a tornado or two are all possible. ...Synopsis... A large-scale mid/upper-level trough is forecast to amplify across the eastern CONUS on Thanksgiving Day. Within the larger trough, one shortwave will take on a negative tilt as it moves quickly east-northeastward from the OH/TN Valley region toward the Mid Atlantic and New England. In the wake of this leading shortwave trough, a northern-stream shortwave will move southeastward from the northern Great Plains toward the Ohio Valley by the end of the period. A surface cyclone associated with the leading shortwave will deepen as it moves from the Mid Atlantic toward southern New England and eventually the Canadian Maritimes. A trailing cold front will move across parts of the Carolinas/Virginia and the Southeast. ...Southeast into the Carolinas... Given the inconsistent signal for robust storm development, a Marginal Risk was maintained with this outlook. However, greater probabilities for all hazards may be needed if confidence increases regarding a sufficient coverage of organized storms through the day. Strong deep-layer flow/shear (with 60-80 kt flow at 500 mb) will be in place atop the relatively moist boundary layer across parts of the Southeast/Carolinas, prior to the frontal passage. Prefrontal MLCAPE is expected to generally be in the 500-1000 J/kg range, with higher values possible where stronger diurnal heating occurs. The resulting environment will be conditionally favorable for organized convection due to the strong deep-layer shear and sufficient instability. However, some weakening and veering of low-level flow is expected with time, as the primary cyclone and stronger large-scale ascent move quickly northeastward away from the region. As a result, uncertainty remains regarding the coverage and intensity of storms along/ahead of the front. Thunderstorms may develop or be ongoing during the morning, though the coverage and intensity of early-day convection remains unclear. Gradual intensification of ongoing convection and/or additional storm development will be possible with time, both along the front, and potentially in the warm sector if sufficient heating can remove any lingering MLCINH. The relatively modest large-scale ascent may limit storm coverage, but also potentially allow for a discrete or clustered supercell mode with the storms that do form. Any sustained supercells could pose an all-hazards severe threat, especially from GA into the Carolinas, where stronger low-level flow/shear may persist through the morning into at least the early afternoon, to the south of the surface low track. The 00Z HRRR/FV3 depict potential supercell development along/ahead of the front, but other 00Z HREF members show only minimal to very isolated organized storm development. Other guidance has generally trended toward a faster frontal passage (as depicted by the ECMWF/UKMET), which could be less favorable for organized storm potential due to reduced time for diurnal destabilization. Additional trimming of the Marginal Risk from the north may be needed if the trend toward a faster frontal passage continues. ..Dean.. 11/27/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1208 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...Synopsis... Mid-level troughing will prevail across the eastern half the U.S., with surface high pressure and associated cooler temperatures overspreading much of the CONUS tomorrow (Thursday). While quiescent fire weather conditions are likely over most areas, portions of southern California may see Elevated fire concerns during the day. A surface pressure gradient, induced by widespread high pressure to the east, will support locally strong offshore flow in terrain-favoring areas surrounding the Los Angeles metropolitan area. Specifically, guidance shows 15+ mph sustained offshore winds amid 15-20 percent RH in and near the Ventura Valley area. Given minimal precipitation accumulations, fuels should be at least modestly receptive to wildfire spread, necessitating Elevated highlights this outlook. ..Squitieri.. 11/27/2024 ...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 1208 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...Synopsis... Mid-level troughing will prevail across the eastern half the U.S., with surface high pressure and associated cooler temperatures overspreading much of the CONUS tomorrow (Thursday). While quiescent fire weather conditions are likely over most areas, portions of southern California may see Elevated fire concerns during the day. A surface pressure gradient, induced by widespread high pressure to the east, will support locally strong offshore flow in terrain-favoring areas surrounding the Los Angeles metropolitan area. Specifically, guidance shows 15+ mph sustained offshore winds amid 15-20 percent RH in and near the Ventura Valley area. Given minimal precipitation accumulations, fuels should be at least modestly receptive to wildfire spread, necessitating Elevated highlights this outlook. ..Squitieri.. 11/27/2024 ...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 1208 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...Synopsis... Mid-level troughing will prevail across the eastern half the U.S., with surface high pressure and associated cooler temperatures overspreading much of the CONUS tomorrow (Thursday). While quiescent fire weather conditions are likely over most areas, portions of southern California may see Elevated fire concerns during the day. A surface pressure gradient, induced by widespread high pressure to the east, will support locally strong offshore flow in terrain-favoring areas surrounding the Los Angeles metropolitan area. Specifically, guidance shows 15+ mph sustained offshore winds amid 15-20 percent RH in and near the Ventura Valley area. Given minimal precipitation accumulations, fuels should be at least modestly receptive to wildfire spread, necessitating Elevated highlights this outlook. ..Squitieri.. 11/27/2024 ...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 1208 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...Synopsis... Mid-level troughing will prevail across the eastern half the U.S., with surface high pressure and associated cooler temperatures overspreading much of the CONUS tomorrow (Thursday). While quiescent fire weather conditions are likely over most areas, portions of southern California may see Elevated fire concerns during the day. A surface pressure gradient, induced by widespread high pressure to the east, will support locally strong offshore flow in terrain-favoring areas surrounding the Los Angeles metropolitan area. Specifically, guidance shows 15+ mph sustained offshore winds amid 15-20 percent RH in and near the Ventura Valley area. Given minimal precipitation accumulations, fuels should be at least modestly receptive to wildfire spread, necessitating Elevated highlights this outlook. ..Squitieri.. 11/27/2024 ...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 1208 AM CST Wed Nov 27 2024 Valid 281200Z - 291200Z ...Synopsis... Mid-level troughing will prevail across the eastern half the U.S., with surface high pressure and associated cooler temperatures overspreading much of the CONUS tomorrow (Thursday). While quiescent fire weather conditions are likely over most areas, portions of southern California may see Elevated fire concerns during the day. A surface pressure gradient, induced by widespread high pressure to the east, will support locally strong offshore flow in terrain-favoring areas surrounding the Los Angeles metropolitan area. Specifically, guidance shows 15+ mph sustained offshore winds amid 15-20 percent RH in and near the Ventura Valley area. Given minimal precipitation accumulations, fuels should be at least modestly receptive to wildfire spread, necessitating Elevated highlights this outlook. ..Squitieri.. 11/27/2024 ...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 1202 AM CST Wed Nov 27 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will gradually amplify across the central CONUS as a surface low translates from the Southern Plains to the Atlantic Coast today. Behind a surface cold front, cool temperatures amid surface high pressure will sweep across much of the CONUS west of the Appalachians. As a result, cool and/or moist conditions will prevail, promoting quiescent fire weather conditions across much of the U.S. Downslope flow may occur across much of western TX during the afternoon, supporting dry and windy conditions. However, fuels are marginally receptive at best for fire spread, so any fire weather concerns should remain localized. ..Squitieri.. 11/27/2024 ...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 1202 AM CST Wed Nov 27 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will gradually amplify across the central CONUS as a surface low translates from the Southern Plains to the Atlantic Coast today. Behind a surface cold front, cool temperatures amid surface high pressure will sweep across much of the CONUS west of the Appalachians. As a result, cool and/or moist conditions will prevail, promoting quiescent fire weather conditions across much of the U.S. Downslope flow may occur across much of western TX during the afternoon, supporting dry and windy conditions. However, fuels are marginally receptive at best for fire spread, so any fire weather concerns should remain localized. ..Squitieri.. 11/27/2024 ...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 1202 AM CST Wed Nov 27 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will gradually amplify across the central CONUS as a surface low translates from the Southern Plains to the Atlantic Coast today. Behind a surface cold front, cool temperatures amid surface high pressure will sweep across much of the CONUS west of the Appalachians. As a result, cool and/or moist conditions will prevail, promoting quiescent fire weather conditions across much of the U.S. Downslope flow may occur across much of western TX during the afternoon, supporting dry and windy conditions. However, fuels are marginally receptive at best for fire spread, so any fire weather concerns should remain localized. ..Squitieri.. 11/27/2024 ...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 1202 AM CST Wed Nov 27 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will gradually amplify across the central CONUS as a surface low translates from the Southern Plains to the Atlantic Coast today. Behind a surface cold front, cool temperatures amid surface high pressure will sweep across much of the CONUS west of the Appalachians. As a result, cool and/or moist conditions will prevail, promoting quiescent fire weather conditions across much of the U.S. Downslope flow may occur across much of western TX during the afternoon, supporting dry and windy conditions. However, fuels are marginally receptive at best for fire spread, so any fire weather concerns should remain localized. ..Squitieri.. 11/27/2024 ...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 1202 AM CST Wed Nov 27 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will gradually amplify across the central CONUS as a surface low translates from the Southern Plains to the Atlantic Coast today. Behind a surface cold front, cool temperatures amid surface high pressure will sweep across much of the CONUS west of the Appalachians. As a result, cool and/or moist conditions will prevail, promoting quiescent fire weather conditions across much of the U.S. Downslope flow may occur across much of western TX during the afternoon, supporting dry and windy conditions. However, fuels are marginally receptive at best for fire spread, so any fire weather concerns should remain localized. ..Squitieri.. 11/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1149 PM CST Tue Nov 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Isolated strong to severe storms are possible late tonight into early Thursday morning, from the lower Mississippi Valley into parts of central and northern Alabama. ...Lower Mississippi Valley/Central Gulf Coast States... A mid-level trough will move across the southern and central Plains today, and into the mid Mississippi Valley tonight. Ahead of the system, low-level moisture will return northward into the lower Mississippi Valley and central Gulf Coast states. A capping inversion is expected across the moist sector, which should limit convective potential through much of the evening. As large-ascent and mid-level temperatures cool due to the approach of the trough, isolated to scattered convective development will become likely from late evening in the overnight across central and northern Mississippi. RAP forecast soundings in north-central Mississippi by 06Z/Thursday have MLCAPE approaching 1000 J/kg, with 0-6 km shear around 50 knots. This could support isolated supercell development as convective coverage increases in the 06Z to 12Z timeframe. Isolated severe wind gusts will be possible with rotating cells. In addition, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 near the instability axis during the overnight, suggesting potential for an isolated tornado threat. 700-500 mb lapse rates around 8 C/km may also support a marginal hail threat. As the storms move eastward into western and northern Alabama from late tonight into the early morning hours on Thursday, an isolated severe threat will likely continue. ..Broyles/Squitieri.. 11/27/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1149 PM CST Tue Nov 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Isolated strong to severe storms are possible late tonight into early Thursday morning, from the lower Mississippi Valley into parts of central and northern Alabama. ...Lower Mississippi Valley/Central Gulf Coast States... A mid-level trough will move across the southern and central Plains today, and into the mid Mississippi Valley tonight. Ahead of the system, low-level moisture will return northward into the lower Mississippi Valley and central Gulf Coast states. A capping inversion is expected across the moist sector, which should limit convective potential through much of the evening. As large-ascent and mid-level temperatures cool due to the approach of the trough, isolated to scattered convective development will become likely from late evening in the overnight across central and northern Mississippi. RAP forecast soundings in north-central Mississippi by 06Z/Thursday have MLCAPE approaching 1000 J/kg, with 0-6 km shear around 50 knots. This could support isolated supercell development as convective coverage increases in the 06Z to 12Z timeframe. Isolated severe wind gusts will be possible with rotating cells. In addition, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 near the instability axis during the overnight, suggesting potential for an isolated tornado threat. 700-500 mb lapse rates around 8 C/km may also support a marginal hail threat. As the storms move eastward into western and northern Alabama from late tonight into the early morning hours on Thursday, an isolated severe threat will likely continue. ..Broyles/Squitieri.. 11/27/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1149 PM CST Tue Nov 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Isolated strong to severe storms are possible late tonight into early Thursday morning, from the lower Mississippi Valley into parts of central and northern Alabama. ...Lower Mississippi Valley/Central Gulf Coast States... A mid-level trough will move across the southern and central Plains today, and into the mid Mississippi Valley tonight. Ahead of the system, low-level moisture will return northward into the lower Mississippi Valley and central Gulf Coast states. A capping inversion is expected across the moist sector, which should limit convective potential through much of the evening. As large-ascent and mid-level temperatures cool due to the approach of the trough, isolated to scattered convective development will become likely from late evening in the overnight across central and northern Mississippi. RAP forecast soundings in north-central Mississippi by 06Z/Thursday have MLCAPE approaching 1000 J/kg, with 0-6 km shear around 50 knots. This could support isolated supercell development as convective coverage increases in the 06Z to 12Z timeframe. Isolated severe wind gusts will be possible with rotating cells. In addition, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 near the instability axis during the overnight, suggesting potential for an isolated tornado threat. 700-500 mb lapse rates around 8 C/km may also support a marginal hail threat. As the storms move eastward into western and northern Alabama from late tonight into the early morning hours on Thursday, an isolated severe threat will likely continue. ..Broyles/Squitieri.. 11/27/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1149 PM CST Tue Nov 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Isolated strong to severe storms are possible late tonight into early Thursday morning, from the lower Mississippi Valley into parts of central and northern Alabama. ...Lower Mississippi Valley/Central Gulf Coast States... A mid-level trough will move across the southern and central Plains today, and into the mid Mississippi Valley tonight. Ahead of the system, low-level moisture will return northward into the lower Mississippi Valley and central Gulf Coast states. A capping inversion is expected across the moist sector, which should limit convective potential through much of the evening. As large-ascent and mid-level temperatures cool due to the approach of the trough, isolated to scattered convective development will become likely from late evening in the overnight across central and northern Mississippi. RAP forecast soundings in north-central Mississippi by 06Z/Thursday have MLCAPE approaching 1000 J/kg, with 0-6 km shear around 50 knots. This could support isolated supercell development as convective coverage increases in the 06Z to 12Z timeframe. Isolated severe wind gusts will be possible with rotating cells. In addition, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 near the instability axis during the overnight, suggesting potential for an isolated tornado threat. 700-500 mb lapse rates around 8 C/km may also support a marginal hail threat. As the storms move eastward into western and northern Alabama from late tonight into the early morning hours on Thursday, an isolated severe threat will likely continue. ..Broyles/Squitieri.. 11/27/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1149 PM CST Tue Nov 26 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST STATES... ...SUMMARY... Isolated strong to severe storms are possible late tonight into early Thursday morning, from the lower Mississippi Valley into parts of central and northern Alabama. ...Lower Mississippi Valley/Central Gulf Coast States... A mid-level trough will move across the southern and central Plains today, and into the mid Mississippi Valley tonight. Ahead of the system, low-level moisture will return northward into the lower Mississippi Valley and central Gulf Coast states. A capping inversion is expected across the moist sector, which should limit convective potential through much of the evening. As large-ascent and mid-level temperatures cool due to the approach of the trough, isolated to scattered convective development will become likely from late evening in the overnight across central and northern Mississippi. RAP forecast soundings in north-central Mississippi by 06Z/Thursday have MLCAPE approaching 1000 J/kg, with 0-6 km shear around 50 knots. This could support isolated supercell development as convective coverage increases in the 06Z to 12Z timeframe. Isolated severe wind gusts will be possible with rotating cells. In addition, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 near the instability axis during the overnight, suggesting potential for an isolated tornado threat. 700-500 mb lapse rates around 8 C/km may also support a marginal hail threat. As the storms move eastward into western and northern Alabama from late tonight into the early morning hours on Thursday, an isolated severe threat will likely continue. ..Broyles/Squitieri.. 11/27/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 PM CST Tue Nov 26 2024 Valid 270100Z - 271200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the continental U.S. tonight. ...DISCUSSION... A zonal mid-level flow pattern will be in place tonight across the continental U.S. At the surface, a cool and relatively dry airmass across much of the nation, will limit thunderstorm potential through tonight. ..Broyles.. 11/27/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 PM CST Tue Nov 26 2024 Valid 270100Z - 271200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the continental U.S. tonight. ...DISCUSSION... A zonal mid-level flow pattern will be in place tonight across the continental U.S. At the surface, a cool and relatively dry airmass across much of the nation, will limit thunderstorm potential through tonight. ..Broyles.. 11/27/2024 Read more