Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0147 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 Sun Aug 18 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST INTO CENTRAL NEVADA... ...Synopsis... A mid-level impulse embedded in the broader cyclonic flow aloft will traverse the West Coast and impinge on the Pacific Northwest while an upper ridge persists across the central U.S. today. The departure of upper support will result in somewhat weaker isallobaric flow from the lee of the Cascades into the Great Basin compared to yesterday. Nonetheless, some residual gradient flow, combined with robust boundary layer mixing, will support dry and windy conditions during the afternoon to the lee of the Sierra into the western Great Basin, where Elevated highlights have been maintained. Critical highlights remain where guidance consensus shows the greatest chance of 20+ mph sustained southwesterly surface winds overlapping with 15 percent RH and fuels receptive to wildfire spread. ..Squitieri.. 08/18/2024 ...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 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 18 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH CAROLINA...THE MID-ATLANTIC...SABINE RIVER VALLEY...AND FROM THE CENTRAL AND NORTHERN HIGH PLAINS INTO THE NORTHERN ROCKIES... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible on Monday over the eastern half of North Carolina into the Mid-Atlantic, and from far east Texas into Louisiana. Isolated severe wind gusts and hail may occur from parts of the central and northern High Plains into the northern Rockies. ...North Carolina/Mid-Atlantic... An upper-level trough will move across the eastern U.S. on Monday, as an associated cold front advances eastward into the coastal areas of the middle Atlantic Seaboard. Along and ahead of the front, surface dewpoints are forecast to be in the lower 70s F. This will result in weak instability by early afternoon near the coast from North Carolina into the Mid-Atlantic. Surface heating and increasing low-level convergence along the front will enable thunderstorms to form during the afternoon. Additional storms are forecast to develop in the post-frontal airmass. In most areas, forecast soundings suggest that 0-6 km shear will be around 30 knots with 0-3 km lapse rates peaking in the 7 to 7.5 C/km range. This could be enough for isolated severe wind gusts associated with the stronger multicells during the mid to late aftennnoon. ...Far East Texas/Louisiana... North-northwesterly mid-level flow will be in place on Monday over much of the central U.S. At the surface, a cold front will be located across the Red River and Sabine River Valleys. Surface dewpoints are forecast to be in the lower 70s F from east Texas into western and central Louisiana. This will contribute to a narrow corridor of moderate instability by afternoon. Isolated thunderstorms may form along and to the east of this axis of instability with storms moving south-southeastward toward the Gulf Coast during the mid to late afternoon. A consensus of model forecasts at this time in the Sabine River Valley Monday currently have MLCAPE peaking in the 2000 to 3000 J/kg range, with 0-6 km shear near 30 knots. This would support an isolated severe threat, with a potential for marginally severe wind gusts. ...Central and Northern High Plains/Northern Rockies... An upper-level ridge is forecast to move eastward across the central and northern High Plains on Monday. To the west of the ridge, an axis of moderate instability will be in place by afternoon from eastern Colorado northward into the western Dakotas and eastern Montana. As surface temperatures warm during the day, convection will likely form in the higher terrain. Additional more isolated storms may develop in the lower elevations. Forecast soundings along and near the instability axis by mid to late afternoon have MLCAPE peaking in the 1000 to 2000 J/kg range, with 0-3 km lapse rates becoming very steep. This, combined with relatively large surface temperature-dewpoint spreads should be favorable for high-based storms associated with isolated severe wind gusts. Hail will also be possible with the stronger cores. ..Broyles.. 08/18/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDDLE ATLANTIC TO THE DEEP SOUTH... ...SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ...Middle Atlantic to Deep South... Great Lakes/OH Valley upper trough will shift east today with a 19/00z position forecast along the spine of the Appalachians. Modest 500mb flow should extend within the base of the trough into the Middle Atlantic. This flow regime will aid the organizational potential of convection that evolves ahead of the primary synoptic front. Latest model guidance suggests a weak surface low may develop over northern VA/MD by late afternoon and this feature should track into NJ during the overnight hours. While deep-layer flow is not forecast to be exceptionally strong, 0-6km bulk shear will exceed 30kt within a warm-advection zone. Forecast soundings favor storm rotation and a few supercells may ultimately evolve across this region. In addition to damaging wind threat, some risk for hail and perhaps a brief tornado can be expected. Trailing front across the Deep South will not be particularly convergent as it surges into GA-AL-MS. Pre-frontal boundary layer will be adequately buoyant for robust updrafts and any storms that evolve ahead of the wind shift will do so within an environment that favors some organization. Convection will propagate southeast toward the Gulf Coast as northwesterly flow deepens with trough passage. ...Rockies/Central Plains... Water-vapor imagery depicts a well-defined short-wave trough topping the Rockies ridge over western WY at this time. This feature will track southeast across the central Plains this afternoon as a 500mb speed max translates into the lower MO Valley. LLJ will respond to this feature which should contribute to an extensive zone of elevated convection early in the period. This activity will propagate southeast along a sharp corridor of warm advection into eastern KS, then into the lower MS Valley during the overnight hours. Have increased severe probabilities to account for this evolution. Primary concern is damaging winds. ...Interior West... Isolated strong/locally severe thunderstorms will once again develop across western UT and track north-northeast along the western/northern periphery of the dominant anticyclone. Gusty winds are possible with this diurnally enhanced activity. ..Darrow/Squitieri.. 08/18/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDDLE ATLANTIC TO THE DEEP SOUTH... ...SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ...Middle Atlantic to Deep South... Great Lakes/OH Valley upper trough will shift east today with a 19/00z position forecast along the spine of the Appalachians. Modest 500mb flow should extend within the base of the trough into the Middle Atlantic. This flow regime will aid the organizational potential of convection that evolves ahead of the primary synoptic front. Latest model guidance suggests a weak surface low may develop over northern VA/MD by late afternoon and this feature should track into NJ during the overnight hours. While deep-layer flow is not forecast to be exceptionally strong, 0-6km bulk shear will exceed 30kt within a warm-advection zone. Forecast soundings favor storm rotation and a few supercells may ultimately evolve across this region. In addition to damaging wind threat, some risk for hail and perhaps a brief tornado can be expected. Trailing front across the Deep South will not be particularly convergent as it surges into GA-AL-MS. Pre-frontal boundary layer will be adequately buoyant for robust updrafts and any storms that evolve ahead of the wind shift will do so within an environment that favors some organization. Convection will propagate southeast toward the Gulf Coast as northwesterly flow deepens with trough passage. ...Rockies/Central Plains... Water-vapor imagery depicts a well-defined short-wave trough topping the Rockies ridge over western WY at this time. This feature will track southeast across the central Plains this afternoon as a 500mb speed max translates into the lower MO Valley. LLJ will respond to this feature which should contribute to an extensive zone of elevated convection early in the period. This activity will propagate southeast along a sharp corridor of warm advection into eastern KS, then into the lower MS Valley during the overnight hours. Have increased severe probabilities to account for this evolution. Primary concern is damaging winds. ...Interior West... Isolated strong/locally severe thunderstorms will once again develop across western UT and track north-northeast along the western/northern periphery of the dominant anticyclone. Gusty winds are possible with this diurnally enhanced activity. ..Darrow/Squitieri.. 08/18/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDDLE ATLANTIC TO THE DEEP SOUTH... ...SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ...Middle Atlantic to Deep South... Great Lakes/OH Valley upper trough will shift east today with a 19/00z position forecast along the spine of the Appalachians. Modest 500mb flow should extend within the base of the trough into the Middle Atlantic. This flow regime will aid the organizational potential of convection that evolves ahead of the primary synoptic front. Latest model guidance suggests a weak surface low may develop over northern VA/MD by late afternoon and this feature should track into NJ during the overnight hours. While deep-layer flow is not forecast to be exceptionally strong, 0-6km bulk shear will exceed 30kt within a warm-advection zone. Forecast soundings favor storm rotation and a few supercells may ultimately evolve across this region. In addition to damaging wind threat, some risk for hail and perhaps a brief tornado can be expected. Trailing front across the Deep South will not be particularly convergent as it surges into GA-AL-MS. Pre-frontal boundary layer will be adequately buoyant for robust updrafts and any storms that evolve ahead of the wind shift will do so within an environment that favors some organization. Convection will propagate southeast toward the Gulf Coast as northwesterly flow deepens with trough passage. ...Rockies/Central Plains... Water-vapor imagery depicts a well-defined short-wave trough topping the Rockies ridge over western WY at this time. This feature will track southeast across the central Plains this afternoon as a 500mb speed max translates into the lower MO Valley. LLJ will respond to this feature which should contribute to an extensive zone of elevated convection early in the period. This activity will propagate southeast along a sharp corridor of warm advection into eastern KS, then into the lower MS Valley during the overnight hours. Have increased severe probabilities to account for this evolution. Primary concern is damaging winds. ...Interior West... Isolated strong/locally severe thunderstorms will once again develop across western UT and track north-northeast along the western/northern periphery of the dominant anticyclone. Gusty winds are possible with this diurnally enhanced activity. ..Darrow/Squitieri.. 08/18/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDDLE ATLANTIC TO THE DEEP SOUTH... ...SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ...Middle Atlantic to Deep South... Great Lakes/OH Valley upper trough will shift east today with a 19/00z position forecast along the spine of the Appalachians. Modest 500mb flow should extend within the base of the trough into the Middle Atlantic. This flow regime will aid the organizational potential of convection that evolves ahead of the primary synoptic front. Latest model guidance suggests a weak surface low may develop over northern VA/MD by late afternoon and this feature should track into NJ during the overnight hours. While deep-layer flow is not forecast to be exceptionally strong, 0-6km bulk shear will exceed 30kt within a warm-advection zone. Forecast soundings favor storm rotation and a few supercells may ultimately evolve across this region. In addition to damaging wind threat, some risk for hail and perhaps a brief tornado can be expected. Trailing front across the Deep South will not be particularly convergent as it surges into GA-AL-MS. Pre-frontal boundary layer will be adequately buoyant for robust updrafts and any storms that evolve ahead of the wind shift will do so within an environment that favors some organization. Convection will propagate southeast toward the Gulf Coast as northwesterly flow deepens with trough passage. ...Rockies/Central Plains... Water-vapor imagery depicts a well-defined short-wave trough topping the Rockies ridge over western WY at this time. This feature will track southeast across the central Plains this afternoon as a 500mb speed max translates into the lower MO Valley. LLJ will respond to this feature which should contribute to an extensive zone of elevated convection early in the period. This activity will propagate southeast along a sharp corridor of warm advection into eastern KS, then into the lower MS Valley during the overnight hours. Have increased severe probabilities to account for this evolution. Primary concern is damaging winds. ...Interior West... Isolated strong/locally severe thunderstorms will once again develop across western UT and track north-northeast along the western/northern periphery of the dominant anticyclone. Gusty winds are possible with this diurnally enhanced activity. ..Darrow/Squitieri.. 08/18/2024 Read more