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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...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 1236 AM CST Wed Dec 11 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated fire weather conditions are expected to persist along the southern CA coast through at least the morning hours today. A prolonged offshore wind event continues to wane along the southern CA coast, but 06 UTC surface observations continue to show areas of elevated to critical fire weather conditions within the higher coastal terrain. Multiple sites continue to report sustained offshore winds of 15-20 mph with frequent gusts of 25-35 mph. Additionally, nearly 12 hours of downslope warming/drying has resulted in widespread RH reductions into the single digits and teens. These conditions are expected to persist through the morning hours as a surface high over the Great Basin migrates east in the wake of a highly amplified upper trough over the central U.S. Upper-level ridging building through the day will promote diminishing low- to mid-level winds by afternoon, but ample diurnal heating and some degree of subsidence warming will maintain the very dry conditions. As such, the primary fire weather concern will be focused during the morning hours with dry, but calmer, conditions through the afternoon. ..Moore.. 12/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Wed Dec 11 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... In the wake of a strong shortwave trough moving into the Canadian Maritimes, a mid/upper cyclone is forecast to progress from the Ontario/Quebec border vicinity eastward through Quebec on Thursday. Strong mid-level flow throughout the base of this cyclone is expected to extend from the northern/central Plains through the Northeast. Even with these strong dynamics, extensive surface ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Consequently, no thunderstorms are anticipated. Farther west, a low-amplitude shortwave trough is expected to progress across the Great Basin into the Four Corners region while enhanced mid-level westerly flow associated with it spreads from southern CA across the Southwest. Some modified moisture return is anticipated across south TX late Thursday night/early Friday morning, but this will remain well downstream of the shortwave trough. As such, the lack of moisture/buoyancy ahead of this shortwave will preclude thunderstorm development. ..Mosier.. 12/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF SOUTHERN NEW ENGLAND ALONG THE ATLANTIC COAST SOUTH TO FAR NORTHEASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe thunderstorms are possible today across the East Coast States, as far north as southern New England. The most probable area for a few tornadoes and damaging winds appears to be centered on eastern North Carolina from midday onward. ...Synopsis... South of a closed low over the western Ontario area, a strong/high-amplitude trough initially aligned roughly along the Mississippi Valley will shift rapidly eastward and then northeastward, acquiring substantial negative tilt with time. At the surface, a cold front will sweep eastward, clearing most of the coast through the afternoon, and eventually shifting southward and off the southern Florida coast/the Keys during the evening hours. ...Southern Atlantic Coast states... As a cold front advances eastward across the East Coast states through the morning and afternoon hours, strong ascent forced by the potent/advancing upper trough will support showers and embedded thunderstorms within the weakly unstable warm sector. Despite the thermodynamic deficiencies that are expected, a high-end wind field will exist, with flow veering gradually and increasing rapidly in magnitude with height. Resulting shear will favor supercells with any semi-discrete storms, while linear organization is also expected in an overall mixed-mode evolution. Along with potential for damaging wind gusts, a few tornadoes are also expected. The greatest risk appears to exist across the eastern North Carolina/Coastal Plain area, during the afternoon. Weaker flow aloft farther south into Florida suggests limiting southern extent of the SLGT risk area to the far northeastern South Carolina vicinity, similar to prior forecasts. Risk will end in most areas by late afternoon, as the front moves offshore in all areas except Florida, before finally clearing the Peninsula after dark. ...Mid-Atlantic region to southern New England... As a surface low deepens over the central Appalachians region and moves quickly northward through the day, low-topped convection near the trailing cold front may evolve into broken linear segments. The boundary layer is forecast to remain stable, with potential a couple hundred J/kg CAPE above 850 to 900mb, sufficient for occasional/sporadic lightning. Meanwhile, extremely strong low-level flow is expected, which will support very fast-moving convection. Given the strongly dynamic synoptic setup as the upper trough takes on increasingly negative tilt, the overall setup suggests locally strong wind gusts despite the surface-based stable layer. As such, will raise damaging wind probability to 15% and thus introduce SLGT risk to parts of southern New England and coastal areas of the Mid-Atlantic region, with some gusts in excess of 60 MPH expected. ..Goss/Moore.. 12/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF SOUTHERN NEW ENGLAND ALONG THE ATLANTIC COAST SOUTH TO FAR NORTHEASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe thunderstorms are possible today across the East Coast States, as far north as southern New England. The most probable area for a few tornadoes and damaging winds appears to be centered on eastern North Carolina from midday onward. ...Synopsis... South of a closed low over the western Ontario area, a strong/high-amplitude trough initially aligned roughly along the Mississippi Valley will shift rapidly eastward and then northeastward, acquiring substantial negative tilt with time. At the surface, a cold front will sweep eastward, clearing most of the coast through the afternoon, and eventually shifting southward and off the southern Florida coast/the Keys during the evening hours. ...Southern Atlantic Coast states... As a cold front advances eastward across the East Coast states through the morning and afternoon hours, strong ascent forced by the potent/advancing upper trough will support showers and embedded thunderstorms within the weakly unstable warm sector. Despite the thermodynamic deficiencies that are expected, a high-end wind field will exist, with flow veering gradually and increasing rapidly in magnitude with height. Resulting shear will favor supercells with any semi-discrete storms, while linear organization is also expected in an overall mixed-mode evolution. Along with potential for damaging wind gusts, a few tornadoes are also expected. The greatest risk appears to exist across the eastern North Carolina/Coastal Plain area, during the afternoon. Weaker flow aloft farther south into Florida suggests limiting southern extent of the SLGT risk area to the far northeastern South Carolina vicinity, similar to prior forecasts. Risk will end in most areas by late afternoon, as the front moves offshore in all areas except Florida, before finally clearing the Peninsula after dark. ...Mid-Atlantic region to southern New England... As a surface low deepens over the central Appalachians region and moves quickly northward through the day, low-topped convection near the trailing cold front may evolve into broken linear segments. The boundary layer is forecast to remain stable, with potential a couple hundred J/kg CAPE above 850 to 900mb, sufficient for occasional/sporadic lightning. Meanwhile, extremely strong low-level flow is expected, which will support very fast-moving convection. Given the strongly dynamic synoptic setup as the upper trough takes on increasingly negative tilt, the overall setup suggests locally strong wind gusts despite the surface-based stable layer. As such, will raise damaging wind probability to 15% and thus introduce SLGT risk to parts of southern New England and coastal areas of the Mid-Atlantic region, with some gusts in excess of 60 MPH expected. ..Goss/Moore.. 12/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF SOUTHERN NEW ENGLAND ALONG THE ATLANTIC COAST SOUTH TO FAR NORTHEASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe thunderstorms are possible today across the East Coast States, as far north as southern New England. The most probable area for a few tornadoes and damaging winds appears to be centered on eastern North Carolina from midday onward. ...Synopsis... South of a closed low over the western Ontario area, a strong/high-amplitude trough initially aligned roughly along the Mississippi Valley will shift rapidly eastward and then northeastward, acquiring substantial negative tilt with time. At the surface, a cold front will sweep eastward, clearing most of the coast through the afternoon, and eventually shifting southward and off the southern Florida coast/the Keys during the evening hours. ...Southern Atlantic Coast states... As a cold front advances eastward across the East Coast states through the morning and afternoon hours, strong ascent forced by the potent/advancing upper trough will support showers and embedded thunderstorms within the weakly unstable warm sector. Despite the thermodynamic deficiencies that are expected, a high-end wind field will exist, with flow veering gradually and increasing rapidly in magnitude with height. Resulting shear will favor supercells with any semi-discrete storms, while linear organization is also expected in an overall mixed-mode evolution. Along with potential for damaging wind gusts, a few tornadoes are also expected. The greatest risk appears to exist across the eastern North Carolina/Coastal Plain area, during the afternoon. Weaker flow aloft farther south into Florida suggests limiting southern extent of the SLGT risk area to the far northeastern South Carolina vicinity, similar to prior forecasts. Risk will end in most areas by late afternoon, as the front moves offshore in all areas except Florida, before finally clearing the Peninsula after dark. ...Mid-Atlantic region to southern New England... As a surface low deepens over the central Appalachians region and moves quickly northward through the day, low-topped convection near the trailing cold front may evolve into broken linear segments. The boundary layer is forecast to remain stable, with potential a couple hundred J/kg CAPE above 850 to 900mb, sufficient for occasional/sporadic lightning. Meanwhile, extremely strong low-level flow is expected, which will support very fast-moving convection. Given the strongly dynamic synoptic setup as the upper trough takes on increasingly negative tilt, the overall setup suggests locally strong wind gusts despite the surface-based stable layer. As such, will raise damaging wind probability to 15% and thus introduce SLGT risk to parts of southern New England and coastal areas of the Mid-Atlantic region, with some gusts in excess of 60 MPH expected. ..Goss/Moore.. 12/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF SOUTHERN NEW ENGLAND ALONG THE ATLANTIC COAST SOUTH TO FAR NORTHEASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe thunderstorms are possible today across the East Coast States, as far north as southern New England. The most probable area for a few tornadoes and damaging winds appears to be centered on eastern North Carolina from midday onward. ...Synopsis... South of a closed low over the western Ontario area, a strong/high-amplitude trough initially aligned roughly along the Mississippi Valley will shift rapidly eastward and then northeastward, acquiring substantial negative tilt with time. At the surface, a cold front will sweep eastward, clearing most of the coast through the afternoon, and eventually shifting southward and off the southern Florida coast/the Keys during the evening hours. ...Southern Atlantic Coast states... As a cold front advances eastward across the East Coast states through the morning and afternoon hours, strong ascent forced by the potent/advancing upper trough will support showers and embedded thunderstorms within the weakly unstable warm sector. Despite the thermodynamic deficiencies that are expected, a high-end wind field will exist, with flow veering gradually and increasing rapidly in magnitude with height. Resulting shear will favor supercells with any semi-discrete storms, while linear organization is also expected in an overall mixed-mode evolution. Along with potential for damaging wind gusts, a few tornadoes are also expected. The greatest risk appears to exist across the eastern North Carolina/Coastal Plain area, during the afternoon. Weaker flow aloft farther south into Florida suggests limiting southern extent of the SLGT risk area to the far northeastern South Carolina vicinity, similar to prior forecasts. Risk will end in most areas by late afternoon, as the front moves offshore in all areas except Florida, before finally clearing the Peninsula after dark. ...Mid-Atlantic region to southern New England... As a surface low deepens over the central Appalachians region and moves quickly northward through the day, low-topped convection near the trailing cold front may evolve into broken linear segments. The boundary layer is forecast to remain stable, with potential a couple hundred J/kg CAPE above 850 to 900mb, sufficient for occasional/sporadic lightning. Meanwhile, extremely strong low-level flow is expected, which will support very fast-moving convection. Given the strongly dynamic synoptic setup as the upper trough takes on increasingly negative tilt, the overall setup suggests locally strong wind gusts despite the surface-based stable layer. As such, will raise damaging wind probability to 15% and thus introduce SLGT risk to parts of southern New England and coastal areas of the Mid-Atlantic region, with some gusts in excess of 60 MPH expected. ..Goss/Moore.. 12/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF SOUTHERN NEW ENGLAND ALONG THE ATLANTIC COAST SOUTH TO FAR NORTHEASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe thunderstorms are possible today across the East Coast States, as far north as southern New England. The most probable area for a few tornadoes and damaging winds appears to be centered on eastern North Carolina from midday onward. ...Synopsis... South of a closed low over the western Ontario area, a strong/high-amplitude trough initially aligned roughly along the Mississippi Valley will shift rapidly eastward and then northeastward, acquiring substantial negative tilt with time. At the surface, a cold front will sweep eastward, clearing most of the coast through the afternoon, and eventually shifting southward and off the southern Florida coast/the Keys during the evening hours. ...Southern Atlantic Coast states... As a cold front advances eastward across the East Coast states through the morning and afternoon hours, strong ascent forced by the potent/advancing upper trough will support showers and embedded thunderstorms within the weakly unstable warm sector. Despite the thermodynamic deficiencies that are expected, a high-end wind field will exist, with flow veering gradually and increasing rapidly in magnitude with height. Resulting shear will favor supercells with any semi-discrete storms, while linear organization is also expected in an overall mixed-mode evolution. Along with potential for damaging wind gusts, a few tornadoes are also expected. The greatest risk appears to exist across the eastern North Carolina/Coastal Plain area, during the afternoon. Weaker flow aloft farther south into Florida suggests limiting southern extent of the SLGT risk area to the far northeastern South Carolina vicinity, similar to prior forecasts. Risk will end in most areas by late afternoon, as the front moves offshore in all areas except Florida, before finally clearing the Peninsula after dark. ...Mid-Atlantic region to southern New England... As a surface low deepens over the central Appalachians region and moves quickly northward through the day, low-topped convection near the trailing cold front may evolve into broken linear segments. The boundary layer is forecast to remain stable, with potential a couple hundred J/kg CAPE above 850 to 900mb, sufficient for occasional/sporadic lightning. Meanwhile, extremely strong low-level flow is expected, which will support very fast-moving convection. Given the strongly dynamic synoptic setup as the upper trough takes on increasingly negative tilt, the overall setup suggests locally strong wind gusts despite the surface-based stable layer. As such, will raise damaging wind probability to 15% and thus introduce SLGT risk to parts of southern New England and coastal areas of the Mid-Atlantic region, with some gusts in excess of 60 MPH expected. ..Goss/Moore.. 12/11/2024 Read more