Aggregator

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CST Tue Dec 10 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... A mid/upper cyclone is forecast to be over the Ontario/Quebec vicinity early Thursday morning, with cyclonic flow throughout its base extending from the northern/central Plains through the Northeast. This cyclone is expected to gradually shift eastward through Quebec, with the associated cyclonic flow shifting northward and eastward as well. 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. At the surface, extensive ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Modest lee troughing is anticipated across the High Plains ahead of the approaching shortwave. However, scouring of the low-level moisture by an antecedent frontal passage will limit moisture advection, with stable conditions prevailing across the central and southern Plains as well. ..Mosier.. 12/10/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 AM CST Tue Dec 10 2024 Valid 121200Z - 131200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... A mid/upper cyclone is forecast to be over the Ontario/Quebec vicinity early Thursday morning, with cyclonic flow throughout its base extending from the northern/central Plains through the Northeast. This cyclone is expected to gradually shift eastward through Quebec, with the associated cyclonic flow shifting northward and eastward as well. 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. At the surface, extensive ridging is expected from the northern Plains into much of the eastern CONUS, promoting dry and stable conditions. Modest lee troughing is anticipated across the High Plains ahead of the approaching shortwave. However, scouring of the low-level moisture by an antecedent frontal passage will limit moisture advection, with stable conditions prevailing across the central and southern Plains as well. ..Mosier.. 12/10/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0132 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...Synopsis... Elevated to locally critical fire weather conditions are anticipated Wednesday along the southern CA coast as an ongoing offshore wind event begins to wane. This event is expected to peak in intensity this morning (Tuesday) before gradually abating through the late afternoon and overnight hours. Critical (20+ mph) wind speeds will likely be ongoing within the coastal mountains by 12 UTC Wednesday, but winds are expected to weaken steadily through the day as the surface high over the Great Basin shifts southeast into the Four Corners/southern High Plains. Regardless, overnight RH recovery will be minimal due to the long-duration nature of the offshore wind event heading into Wednesday morning, which will promote several hours of elevated to locally critical fire weather conditions (most likely through 18 UTC). By late Wednesday afternoon, 15-25 mph winds should be confined to typically breezy locations within the higher terrain, though widespread 5-15% RH values should persist, given increasing subsidence and diurnal heating. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 0102 AM CST Tue Dec 10 2024 Valid 101200Z - 111200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN CALIFORNIA COAST... ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN CALIFORNIA COAST... ...Synopsis... Critical to extremely critical fire weather conditions are expected today along the southern CA coast, posing a high-end fire weather threat. 06 UTC surface observations within the southern CA coastal mountains are showing widespread RH reductions into the low to mid teens with sustained winds between 25-35 mph and frequent gusts upwards of 40-50 mph (occasionally gusting to 60-75 mph in a few locations). Other observed trends across the region suggest that winds will increase through the early to mid-morning hours (most likely peaking during the 12-17 UTC period). Surface pressure obs across northeast NV are reporting a 1036 mb surface high with further pressure rises to around 1037-1039 mb expected through 15 UTC. Additionally, latest upper-air analyses show a low to mid-level cold front pushing south into southern CA. The arrival of the cooler/more dense air mass and stronger mid-level flow, accompanied by further surface pressure rises, should result in strengthening winds through the morning hours. The observed LAX-DAG pressure gradient has also been trending lower (i.e. stronger) than depicted by most deterministic solutions, but guidance that has captured recent trends well shows increasingly widespread 60+ mph wind gusts within the Sierra Madre, San Gabriel, and San Jacinto mountains by mid-morning. Single-digit RH values will also become more common by the afternoon hours, given the duration of the downslope wind event coupled with the diurnal heating cycle. The prolonged nature of the event is also promoting rapid drying of 1- and 10-hour fuels, which will increase the fire weather threat through the day. Extremely critical wind speeds will gradually begin to abate after roughly 20 UTC, as the surface high over the Great Basin begins to weaken. However, widespread critical fire weather conditions should still persist well into early Wednesday morning. ..Moore.. 12/10/2024 ...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 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CST Tue Dec 10 2024 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NC INTO SOUTHERN NEW ENGLAND... ...SUMMARY... Strong to isolated severe thunderstorms are possible along and ahead of a cold front from eastern North Carolina into southern New England on Wednesday. ...Synopsis... A deep upper trough is expected to extend from central Canada southward along the length of the MS Valley into the western Gulf early Wednesday morning. A shortwave trough embedded within the base of this larger troughing is forecast to move quickly northeastward from the Lower MS Valley into the Mid-Atlantic. In response, the parent upper troughing will shift eastward while also deamplifying. Strong mid/upper flow is anticipated throughout the eastern periphery of this troughing, with a 100-110 kt 500 mb jet shifting northeastward from the Southeast into the Mid-Atlantic throughout the day. An associated surface low will deepen as it moves northeastward from northern VA through the Hudson Valley into NH/VT. An attendant cold front is forecast to sharpens as it moves quickly eastward, moving off the East Coast by Wednesday evening. ...Eastern North Carolina to southern New England... Low to mid 60s dewpoints are expected to advect northward into the Carolinas and northern Mid-Atlantic States ahead of the approaching cold front, with mid to upper 50s possible farther north into southern New England. These dewpoints will support modest buoyancy, with the overall buoyancy tempered by poor mid-level lapse rates and widespread precipitation. Even so, a strongly forced convective line is still expected to develop along the front as it moves quickly eastward across the region during the afternoon. Deeper convection is anticipated in this line when increasing large-scale ascent aligns with the low-level forcing along the front. Guidance differs on when and where this occurs, with some guidance suggesting it occurs primarily offshore. Even so, there is still enough potential for this occur onshore to maintain probabilities for strong gusts. Expectation is for this deeper convection to combine with the robust kinematic fields to provide a large reservoir of high-momentum air capable of mixing down to the surface. Given the strength of the forcing, this potential exists as far north across southern New England where buoyancy is expected to be very low. Additionally, some potential exists for surface-based storms within the warm sector ahead of the front, provided that antecedent precipitation does not entirely stabilize the low levels. Some guidance suggests a pre-frontal band of surface-based storms develops with low-level confluence within the warm sector over coastal NC and the Outer Banks. ..Mosier.. 12/10/2024 Read more