Severe Storms

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0314 PM CDT Sun Sep 29 2024 Valid 011200Z - 071200Z Fire weather concerns may persist through the early parts of the upcoming work week across parts of the Rockies and High Plains, but confidence in robust fire weather concerns abates heading into the later parts of the week. Long-range guidance shows reasonably good agreement in a gradually building upper ridge over the central CONUS through the next 7 days. This will maintain relatively dry conditions across the central Rockies and Plains where fuels are fairly dry. This upper-air regime will also favor surface low development primarily across the Canadian Prairies with occasional cold frontal intrusions into the Plains. Fire weather concerns will likely emerge as winds increase with each of these dry frontal passages. ...D3/Tuesday - High Plains and southern Wyoming... Breezy pressure gradient winds are anticipated along the central to northern High Plains D3/Tuesday afternoon amid weak troughing in the lee of the Canadian Rockies juxtaposed with a strong surface high over the central Great Plains. Winds generally in the 15-20 mph range appear most likely per recent ensemble solutions, but some locations may see winds up to 20-25 mph. Dry conditions will persist from this weekend into early next week with 15-25% RH expected by peak heating. Consequently, elevated to locally critical fire weather conditions appear possible. Fire weather concerns may emerge across the Wyoming Basin as well within a westerly downslope flow regime; however, stronger mid-level flow is expected to be displaced to the north which limits confidence in a robust/sustained fire weather threat. ..Moore.. 09/29/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Sun Sep 29 2024 Valid 292000Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast for today. ...20Z Update... The previous forecast (see below) remains unchanged. ..Squitieri.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Sep 29 2024/ ...Synopsis... A relatively quiet convective day is expected across the CONUS today. Over portions of UT, weak/peripheral midlevel height falls will promote isolated high-based thunderstorms capable of locally strong gusts, aided by inverted-V thermodynamic profiles. Weak instability and flow/shear should limit thunderstorm intensity and organization. Farther east, isolated thunderstorms will be possible this afternoon and evening over portions of the OH Valley into the Mid-Atlantic -- ahead of a vertically stacked/weakening cyclone. Very poor deep-layer lapse rates and warm air aloft may limit lightning over many areas, though a few isolated flashes cannot be ruled out, given some large-scale ascent. Ahead of a quasi-stationary front draped across northern FL, diurnal heating of a moist/uncapped air mass will support isolated to widely scattered thunderstorms across the FL Peninsula this afternoon. Locally strong water-loaded downbursts could accompany a couple storms over northeast FL, where low-level convergence and midlevel flow will be slightly stronger. However, poor midlevel lapse rates and only marginal deep-layer shear should limit the severe threat. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...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 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...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 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...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 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...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 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...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 0149 PM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL TO NORTHERN PLAINS... ...Central and Northern Plains... Both the Elevated and Critical fire weather risk areas have been expanded to encompass more of the central and northern Plains based on trends in recent guidance. Nearly all solutions, including the typically moist NAM-based solutions, have trended towards a faster cold frontal progression through Monday evening with widespread 15-25% RH reductions and 20-30 mph winds in the post-frontal regime. The general consensus among deterministic and ensemble guidance is that much of central NE and south-central SD will see several hours of critical wind/RH conditions, and elevated conditions may extend as far east as the upper MS River Valley (though some uncertainty persist regarding how far east the cold front will reach by late afternoon). ERCs generally remain above the 80th percentile across the central/northern Plains and will support the fire weather concern. ...Northeast Utah into Wyoming... An Elevated risk area has been introduced for portions of northeast UT into southwest WY. Breezy westerly winds in the wake of the synoptic cold front should promote downslope warming/drying in the lee of the Wasatch and Uinta Mountains. With the stronger gradient winds displaced to the east, 15-20 mph winds appear most likely, but a few locations may see winds up to 20-25 mph with RH reductions into the teens and low 20s. ..Moore.. 09/29/2024 .PREV DISCUSSION... /ISSUED 1244 AM CDT Sun Sep 29 2024/ ...Synopsis... A southeastward-moving cold front will bring elevated to critical fire-weather conditions to the central and northern Great Plains. Gusty winds of 20-25 MPH will coincide with post-frontal boundary-layer relative humidity values of 10-15% across much of South Dakota into Nebraska and northern Kansas. These conditions will overlap with ERC fuels that exceed the 98th annual percentile, and warm/dry conditions expected the preceding day. A Critical highlight area was introduced where the greatest confidence in persistent dry and windy conditions will occur, though additional adjustments and expansions may be needed as frontal timing and speed come into clearer focus. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern NC to far southeast VA during the afternoon before the trough departs. A more substantial upper-level trough will move across ON and the northern Great Lakes. Ahead of the trough, a surface cold front will march east across the central Great Lakes to the Lower OH Valley during the afternoon. Surface dew points ahead of the cold front should be in the low 60s, which will yield a plume of weak buoyancy. Forecast soundings suggest relatively warm 700-mb temperatures will inhibit thunderstorm development ahead of the front. But convergence along it may be sufficient for surface-based thunderstorms across parts of Lower MI into IN/OH during the afternoon. Weak low-level winds and modest deep-layer shear, owing to stronger flow lagging behind the front, should preclude severe storms. The greatest coverage of thunderstorms is most likely across the central FL Peninsula as the moist air mass heats during the day and sea breeze boundaries provide lift. ..Grams.. 09/29/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1156 AM CDT Sun Sep 29 2024 Valid 301200Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Monday. ...Southern VA and the Carolinas... A weakening, positive-tilt mid/upper trough will slowly move eastward over the central/southern Appalachians on Monday. Thermodynamic profiles across the region suggest convection should remain shallow due to relatively warm temperatures at mid/upper levels, especially along/south of the quasi-stationary front arcing from central/southern NC to southern WV. Overall thunderstorm coverage should be quite isolated. On the southeast flank of the trough, mid-level southwesterlies will remain enhanced from GA to southern NC. Adequate deep-layer shear with moderate straight-line hodograph elongation should be present near the southeast NC vicinity of the front. But poor mid-level lapse rates (around 4-5 C/km) will temper hail growth. ...FL Peninsula... Rich low-level moisture combined with ascent along the sea breeze should promote isolated to widely scattered thunderstorms during the afternoon. Weak shear will limit organized severe potential. ...Southwest... Limited mid-level moisture within the upper-level ridge may be adequate for very isolated thunderstorms from the southern Rockies to the Mogollon Rim. Consensus of model soundings suggest buoyancy should be scant at most, with high-based, low-topped convection. Gusty, erratic surface winds are possible within dry microbursts. ..Grams.. 09/29/2024 Read more