Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Fri Sep 05 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe weather appears low on Sunday. ...Synopsis... A large upper trough will affect the Great Lakes to Northeast region, while an upper ridge gradually weakens over the Rockies. High pressure will bring cooler and stable conditions to much of the central and eastern CONUS, as the leading cold front moves into coastal Southeast and toward the northern Gulf. As such, instability for thunderstorms will be limited in area. Afternoon storms do appear likely over the eastern Carolinas during the afternoon as the front lingers. Shear will be weak but a few stronger storms capable of locally gusty winds may occur. To the west, the stalled portion of the front over central TX may yield areas of rain and thunderstorms, but severe appears unlikely. Otherwise, a few nocturnal storms are expected over the central High Plains Sunday night, as southerly winds in the low-levels support a narrow ribbon of moisture/instability. While low-end hail cannot be ruled out, overall potential remains low at this time frame. ..Jewell.. 09/05/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Fri Sep 05 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe weather appears low on Sunday. ...Synopsis... A large upper trough will affect the Great Lakes to Northeast region, while an upper ridge gradually weakens over the Rockies. High pressure will bring cooler and stable conditions to much of the central and eastern CONUS, as the leading cold front moves into coastal Southeast and toward the northern Gulf. As such, instability for thunderstorms will be limited in area. Afternoon storms do appear likely over the eastern Carolinas during the afternoon as the front lingers. Shear will be weak but a few stronger storms capable of locally gusty winds may occur. To the west, the stalled portion of the front over central TX may yield areas of rain and thunderstorms, but severe appears unlikely. Otherwise, a few nocturnal storms are expected over the central High Plains Sunday night, as southerly winds in the low-levels support a narrow ribbon of moisture/instability. While low-end hail cannot be ruled out, overall potential remains low at this time frame. ..Jewell.. 09/05/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...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 0215 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...Update... Some minor changes were made to the Isolated Dry Thunderstorm area for Saturday. The latest model trends regarding the track and ascent associated with the initial mid-level shortwave trough moving onshore suggest additional lightning strikes may occur further west over the Cascades of WA. Farther south, into portions of the northern Great Basin and far southeastern OR, fuels appear far less receptive. Therefore, some of this region was trimmed out of the isolated area. Please see the previous discussion below for additional details. ..Barnes.. 09/05/2025 .PREV DISCUSSION... /ISSUED 0152 AM CDT Fri Sep 05 2025/ ...Synopsis... A mid-level trough will continue to approach the East Coast as upper ridging builds over the Rockies and a mid-level trough remains in place along the Pacific Northwest coast tomorrow (Saturday). A mid-level impulse will pivot around the northwestern trough, providing locally stronger upper support for dry and breezy conditions across northern California into southern Oregon. At the moment, the overlap of 15+ mph sustained southwesterly surface winds amid 15-20 percent RH seem to be too localized to warrant Elevated highlights at this time. Of greater concern is the development of scattered thunderstorms ahead of the mid-level trough over parts of the Pacific Northwest into the northern Rockies. Here, a mix of wet and dry storm modes will overspread a dry boundary layer, as well as dry fuel beds. Storm motions will be relatively slow. However, the high receptiveness of the fuels may compensate for possible wet, slow moving storms to support lightning-induced ignitions, warranting the introduction of isolated dry thunderstorm highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 PM CDT Fri Sep 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE... ...SUMMARY... Scattered strong to severe thunderstorms are most likely Saturday from eastern Pennsylvania and New Jersey into parts of southern New England. Isolated strong gusts are possible extending southward across the Piedmont. ...Synopsis... A leading mid/upper level speed max will pivot northeastward across Quebec on Saturday, with the right-entrance region sweeping across much of the northeastern states. Given the trajectory, only subtle height falls will occur over the region, but midlevel southwest winds will increase to around 60 kt, enhancing deep-layer shear. This cyclonic pattern aloft will extend well south across the Appalachians, where winds will be much weaker. However, relatively cool midlevel temperatures will aid destabilization in these areas. At the surface, a cold front will push east from ME into northern VA, with a moist air mass ahead of it. Winds at 850 mb will increase to 30-40 kt across the Northeast, which will aid the northward transport of moisture and destabilization. ...Northeast... A wave of low pressure is forecast to develop over eastern PA early in the day, translating northeastward along the front and into ME by late afternoon. Stronger heating and steep low-level lapse rates should develop from VA into eastern PA/NJ and into interior southern New England, with MLCAPE around 1500 J/kg as an areal average. As the warm air mass develops and accelerates north ahead of the cold front, both instability and shear parameter space will become favorable for severe storms, including supercell potential. A line of storms is expected by 17 to 18Z, from eastern PA toward the Hudson Valley, expanding N/S and pushing east through the afternoon. Given 40-50 kt effective deep-layer shear and enhanced low-level shear with the midday surface theta-e surge, the initial storm mode may be cellular along the boundary, with a brief tornado or two possible along with some hail. Damaging winds are then most likely as outflows merge, and spread east across the remainder of the region through late afternoon. ...Piedmont... Strong heating will occur across most of the area, with areas of high-level clouds expected across the Appalachians. The moist/uncapped air mass and weak surface trough should yield scattered afternoon storms. Despite weak shear, favorable timing with peak heating/steep boundary layer lapse rates as well as up to 2000 J/kg MUCAPE may yield locally strong to damaging downbursts. A few storms could produce marginal hail given sufficient longevity. ..Jewell.. 09/05/2025 Read more