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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1031 AM CST Tue Nov 28 2023 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/28/2023 .PREV DISCUSSION... /ISSUED 0140 AM CST Tue Nov 28 2023/ ...Synopsis... On the backside of a departing large-scale trough over the Northeast, strong deep-layer west-northwesterly flow will overspread the Southeast. At the same time, surface high pressure will shift east-southeastward from the Great Plains into the central Gulf Coast. Along the eastern periphery of the surface high, an enhanced pressure gradient will support 10-15 mph northwesterly surface winds (with higher gusts), while shallow boundary-layer mixing into dry air aloft favors 25-35 percent minimum RH across portions of the Southeast and southern Appalachians. While locally elevated fire-weather conditions are possible for these areas, recent rainfall and generally cool surface temperatures should limit the overall threat. Farther west, strong northwesterly flow aloft will cross the northern Rockies, yielding dry/breezy downslope flow into the northern High Plains. A lack of appreciable precipitation over this area suggests that fuels are at least modestly receptive, and locally elevated fire-weather conditions are possible. Similar to the Southeast, cool surface temperatures should mitigate the threat. ...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 1031 AM CST Tue Nov 28 2023 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/28/2023 .PREV DISCUSSION... /ISSUED 0140 AM CST Tue Nov 28 2023/ ...Synopsis... On the backside of a departing large-scale trough over the Northeast, strong deep-layer west-northwesterly flow will overspread the Southeast. At the same time, surface high pressure will shift east-southeastward from the Great Plains into the central Gulf Coast. Along the eastern periphery of the surface high, an enhanced pressure gradient will support 10-15 mph northwesterly surface winds (with higher gusts), while shallow boundary-layer mixing into dry air aloft favors 25-35 percent minimum RH across portions of the Southeast and southern Appalachians. While locally elevated fire-weather conditions are possible for these areas, recent rainfall and generally cool surface temperatures should limit the overall threat. Farther west, strong northwesterly flow aloft will cross the northern Rockies, yielding dry/breezy downslope flow into the northern High Plains. A lack of appreciable precipitation over this area suggests that fuels are at least modestly receptive, and locally elevated fire-weather conditions are possible. Similar to the Southeast, cool surface temperatures should mitigate the threat. ...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 1031 AM CST Tue Nov 28 2023 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/28/2023 .PREV DISCUSSION... /ISSUED 0140 AM CST Tue Nov 28 2023/ ...Synopsis... On the backside of a departing large-scale trough over the Northeast, strong deep-layer west-northwesterly flow will overspread the Southeast. At the same time, surface high pressure will shift east-southeastward from the Great Plains into the central Gulf Coast. Along the eastern periphery of the surface high, an enhanced pressure gradient will support 10-15 mph northwesterly surface winds (with higher gusts), while shallow boundary-layer mixing into dry air aloft favors 25-35 percent minimum RH across portions of the Southeast and southern Appalachians. While locally elevated fire-weather conditions are possible for these areas, recent rainfall and generally cool surface temperatures should limit the overall threat. Farther west, strong northwesterly flow aloft will cross the northern Rockies, yielding dry/breezy downslope flow into the northern High Plains. A lack of appreciable precipitation over this area suggests that fuels are at least modestly receptive, and locally elevated fire-weather conditions are possible. Similar to the Southeast, cool surface temperatures should mitigate the threat. ...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 1031 AM CST Tue Nov 28 2023 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/28/2023 .PREV DISCUSSION... /ISSUED 0140 AM CST Tue Nov 28 2023/ ...Synopsis... On the backside of a departing large-scale trough over the Northeast, strong deep-layer west-northwesterly flow will overspread the Southeast. At the same time, surface high pressure will shift east-southeastward from the Great Plains into the central Gulf Coast. Along the eastern periphery of the surface high, an enhanced pressure gradient will support 10-15 mph northwesterly surface winds (with higher gusts), while shallow boundary-layer mixing into dry air aloft favors 25-35 percent minimum RH across portions of the Southeast and southern Appalachians. While locally elevated fire-weather conditions are possible for these areas, recent rainfall and generally cool surface temperatures should limit the overall threat. Farther west, strong northwesterly flow aloft will cross the northern Rockies, yielding dry/breezy downslope flow into the northern High Plains. A lack of appreciable precipitation over this area suggests that fuels are at least modestly receptive, and locally elevated fire-weather conditions are possible. Similar to the Southeast, cool surface temperatures should mitigate the threat. ...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 1031 AM CST Tue Nov 28 2023 Valid 281700Z - 291200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/28/2023 .PREV DISCUSSION... /ISSUED 0140 AM CST Tue Nov 28 2023/ ...Synopsis... On the backside of a departing large-scale trough over the Northeast, strong deep-layer west-northwesterly flow will overspread the Southeast. At the same time, surface high pressure will shift east-southeastward from the Great Plains into the central Gulf Coast. Along the eastern periphery of the surface high, an enhanced pressure gradient will support 10-15 mph northwesterly surface winds (with higher gusts), while shallow boundary-layer mixing into dry air aloft favors 25-35 percent minimum RH across portions of the Southeast and southern Appalachians. While locally elevated fire-weather conditions are possible for these areas, recent rainfall and generally cool surface temperatures should limit the overall threat. Farther west, strong northwesterly flow aloft will cross the northern Rockies, yielding dry/breezy downslope flow into the northern High Plains. A lack of appreciable precipitation over this area suggests that fuels are at least modestly receptive, and locally elevated fire-weather conditions are possible. Similar to the Southeast, cool surface temperatures should mitigate the threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Tue Nov 28 2023 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Synopsis... A midlevel shortwave trough is moving over the Lower Great Lakes now, and subtle veering of flow this afternoon will result in shorter over-lake fetches and reduced depth/organization to the lake effect snow bands. Given the marginal thermodynamic profiles for charge separation, the threat for isolated lightning flashes is expected to diminish through the afternoon. Farther west, a midlevel low will move slowly eastward toward the central/northern CA coast by early Wednesday. There may be sufficient cooling/moistening of profiles for weak buoyancy and isolated lightning flashes near the end of the period along the coast. ..Thompson/Moore.. 11/28/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Tue Nov 28 2023 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Synopsis... A midlevel shortwave trough is moving over the Lower Great Lakes now, and subtle veering of flow this afternoon will result in shorter over-lake fetches and reduced depth/organization to the lake effect snow bands. Given the marginal thermodynamic profiles for charge separation, the threat for isolated lightning flashes is expected to diminish through the afternoon. Farther west, a midlevel low will move slowly eastward toward the central/northern CA coast by early Wednesday. There may be sufficient cooling/moistening of profiles for weak buoyancy and isolated lightning flashes near the end of the period along the coast. ..Thompson/Moore.. 11/28/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Tue Nov 28 2023 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Synopsis... A midlevel shortwave trough is moving over the Lower Great Lakes now, and subtle veering of flow this afternoon will result in shorter over-lake fetches and reduced depth/organization to the lake effect snow bands. Given the marginal thermodynamic profiles for charge separation, the threat for isolated lightning flashes is expected to diminish through the afternoon. Farther west, a midlevel low will move slowly eastward toward the central/northern CA coast by early Wednesday. There may be sufficient cooling/moistening of profiles for weak buoyancy and isolated lightning flashes near the end of the period along the coast. ..Thompson/Moore.. 11/28/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Tue Nov 28 2023 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Synopsis... A midlevel shortwave trough is moving over the Lower Great Lakes now, and subtle veering of flow this afternoon will result in shorter over-lake fetches and reduced depth/organization to the lake effect snow bands. Given the marginal thermodynamic profiles for charge separation, the threat for isolated lightning flashes is expected to diminish through the afternoon. Farther west, a midlevel low will move slowly eastward toward the central/northern CA coast by early Wednesday. There may be sufficient cooling/moistening of profiles for weak buoyancy and isolated lightning flashes near the end of the period along the coast. ..Thompson/Moore.. 11/28/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Tue Nov 28 2023 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Synopsis... A midlevel shortwave trough is moving over the Lower Great Lakes now, and subtle veering of flow this afternoon will result in shorter over-lake fetches and reduced depth/organization to the lake effect snow bands. Given the marginal thermodynamic profiles for charge separation, the threat for isolated lightning flashes is expected to diminish through the afternoon. Farther west, a midlevel low will move slowly eastward toward the central/northern CA coast by early Wednesday. There may be sufficient cooling/moistening of profiles for weak buoyancy and isolated lightning flashes near the end of the period along the coast. ..Thompson/Moore.. 11/28/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CST Tue Nov 28 2023 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Lower Great Lakes... In proximity to the mid-level cold core (-40C at 500 mb) centered over eastern Ontario and Quebec, steep lapse rates persist with lake-induced CAPE and lake effect snow in the lee of the Great Lakes. This low-topped convection may be still conducive to a few lightning flashes through the morning/early afternoon, particularly in the lee of Lake Ontario. ...California coast... A southern-stream trough will approach the California coast late tonight and early Wednesday. Given the expected weakening nature of the approaching surface cyclone, and its offshore forecast track, the potential for appreciable boundary-layer destabilization inland of northern/central coastal areas appears quite low. While mid-level cooling ahead of the modest mid-level cold core (500 mb temperatures around -22 to -24C) may contribute to convection capable of lightning offshore, lightning production with the convection should tend to wane as it approaches central California coastal areas late tonight into early Wednesday. ..Guyer/Mosier.. 11/28/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CST Tue Nov 28 2023 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Lower Great Lakes... In proximity to the mid-level cold core (-40C at 500 mb) centered over eastern Ontario and Quebec, steep lapse rates persist with lake-induced CAPE and lake effect snow in the lee of the Great Lakes. This low-topped convection may be still conducive to a few lightning flashes through the morning/early afternoon, particularly in the lee of Lake Ontario. ...California coast... A southern-stream trough will approach the California coast late tonight and early Wednesday. Given the expected weakening nature of the approaching surface cyclone, and its offshore forecast track, the potential for appreciable boundary-layer destabilization inland of northern/central coastal areas appears quite low. While mid-level cooling ahead of the modest mid-level cold core (500 mb temperatures around -22 to -24C) may contribute to convection capable of lightning offshore, lightning production with the convection should tend to wane as it approaches central California coastal areas late tonight into early Wednesday. ..Guyer/Mosier.. 11/28/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CST Tue Nov 28 2023 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Lower Great Lakes... In proximity to the mid-level cold core (-40C at 500 mb) centered over eastern Ontario and Quebec, steep lapse rates persist with lake-induced CAPE and lake effect snow in the lee of the Great Lakes. This low-topped convection may be still conducive to a few lightning flashes through the morning/early afternoon, particularly in the lee of Lake Ontario. ...California coast... A southern-stream trough will approach the California coast late tonight and early Wednesday. Given the expected weakening nature of the approaching surface cyclone, and its offshore forecast track, the potential for appreciable boundary-layer destabilization inland of northern/central coastal areas appears quite low. While mid-level cooling ahead of the modest mid-level cold core (500 mb temperatures around -22 to -24C) may contribute to convection capable of lightning offshore, lightning production with the convection should tend to wane as it approaches central California coastal areas late tonight into early Wednesday. ..Guyer/Mosier.. 11/28/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CST Tue Nov 28 2023 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Lower Great Lakes... In proximity to the mid-level cold core (-40C at 500 mb) centered over eastern Ontario and Quebec, steep lapse rates persist with lake-induced CAPE and lake effect snow in the lee of the Great Lakes. This low-topped convection may be still conducive to a few lightning flashes through the morning/early afternoon, particularly in the lee of Lake Ontario. ...California coast... A southern-stream trough will approach the California coast late tonight and early Wednesday. Given the expected weakening nature of the approaching surface cyclone, and its offshore forecast track, the potential for appreciable boundary-layer destabilization inland of northern/central coastal areas appears quite low. While mid-level cooling ahead of the modest mid-level cold core (500 mb temperatures around -22 to -24C) may contribute to convection capable of lightning offshore, lightning production with the convection should tend to wane as it approaches central California coastal areas late tonight into early Wednesday. ..Guyer/Mosier.. 11/28/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CST Tue Nov 28 2023 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today or tonight. ...Lower Great Lakes... In proximity to the mid-level cold core (-40C at 500 mb) centered over eastern Ontario and Quebec, steep lapse rates persist with lake-induced CAPE and lake effect snow in the lee of the Great Lakes. This low-topped convection may be still conducive to a few lightning flashes through the morning/early afternoon, particularly in the lee of Lake Ontario. ...California coast... A southern-stream trough will approach the California coast late tonight and early Wednesday. Given the expected weakening nature of the approaching surface cyclone, and its offshore forecast track, the potential for appreciable boundary-layer destabilization inland of northern/central coastal areas appears quite low. While mid-level cooling ahead of the modest mid-level cold core (500 mb temperatures around -22 to -24C) may contribute to convection capable of lightning offshore, lightning production with the convection should tend to wane as it approaches central California coastal areas late tonight into early Wednesday. ..Guyer/Mosier.. 11/28/2023 Read more

MD 2289 CONCERNING HEAVY SNOW FOR WESTERN NY...EXTREME NORTHWEST PA...FAR NORTHEAST OH
Mesoscale Discussion 2289 NWS Storm Prediction Center Norman OK 0116 AM CST Tue Nov 28 2023 Areas affected...Western NY...Extreme Northwest PA...Far Northeast OH Concerning...Heavy snow Valid 280716Z - 281115Z SUMMARY...Heavy snowfall, with rates over 2" per hour, are possible across the Tug Hill Plateau over the next several hours. Moderate to occasionally heavy snowfall is also anticipated farther south in the immediate lee of Lake Erie. DISCUSSION...Recent radar imagery continues to show a loosely organized band of heavy snowfall extending from eastern portions of Lake Ontario eastward through Oswego, southern Jefferson, and Lewis Counties. Overall organization of this band is expected to improve over the next several hours as broad westerly flow across the lake persists, and local convergence increases due to strengthening and veering of the winds south of the lake. Some strengthening is possible with the winds over the lake as well as the more west-northwesterly winds north of the lake. Snowfall rates from 1" to 2" per hour will continue for the next several hours, likely maximizing in the 08Z-10Z time frame, when rates of 2" per hour are most likely. Farther south, a shorter lake fetch is contributing to a broad areas of moderate snowfall in the lee of Lake Erie. Less low-level convergence and weaker band organization should keep snowfall rates a bit lower here than areas farther north, with rates generally expected to maximize around 1" per hour. ..Mosier.. 11/28/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BGM...BUF...CTP...CLE... LAT...LON 43587694 43987619 44157546 43557530 42217781 41548055 41388156 41968137 42697907 43587694 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Tue Nov 28 2023 Valid 011200Z - 061200Z ...DISCUSSION... A pair of embedded shortwave troughs within the larger-scale southwesterlies will move across the OH Valley and southern Plains on Friday/D4, as a cold front sinks southward along the northern Gulf Coast. Ongoing showers and thunderstorms will move quickly east across AL/GA, with only weak instability present. Meanwhile, drying behind this lead system will result in little to no instability for the lagging wave over the Plains. On Saturday/D5, another shortwave trough will move into the central/southern Plains, with minimal moisture return/quality. This wave will take a similar track to the previous ones toward the mid MS Valley, to the north of the better moisture. Nonetheless, scattered showers and storms are likely on D5 and into Sunday/D6 from the northern Gulf Coast into the Southeast. Thereafter, high pressure is again forecast over the Plains, with offshore flow developing over the Gulf of Mexico and East Coast Monday/D7 into Tuesday/D8 as the upper trough amplifies over the East. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Tue Nov 28 2023 Valid 011200Z - 061200Z ...DISCUSSION... A pair of embedded shortwave troughs within the larger-scale southwesterlies will move across the OH Valley and southern Plains on Friday/D4, as a cold front sinks southward along the northern Gulf Coast. Ongoing showers and thunderstorms will move quickly east across AL/GA, with only weak instability present. Meanwhile, drying behind this lead system will result in little to no instability for the lagging wave over the Plains. On Saturday/D5, another shortwave trough will move into the central/southern Plains, with minimal moisture return/quality. This wave will take a similar track to the previous ones toward the mid MS Valley, to the north of the better moisture. Nonetheless, scattered showers and storms are likely on D5 and into Sunday/D6 from the northern Gulf Coast into the Southeast. Thereafter, high pressure is again forecast over the Plains, with offshore flow developing over the Gulf of Mexico and East Coast Monday/D7 into Tuesday/D8 as the upper trough amplifies over the East. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Tue Nov 28 2023 Valid 011200Z - 061200Z ...DISCUSSION... A pair of embedded shortwave troughs within the larger-scale southwesterlies will move across the OH Valley and southern Plains on Friday/D4, as a cold front sinks southward along the northern Gulf Coast. Ongoing showers and thunderstorms will move quickly east across AL/GA, with only weak instability present. Meanwhile, drying behind this lead system will result in little to no instability for the lagging wave over the Plains. On Saturday/D5, another shortwave trough will move into the central/southern Plains, with minimal moisture return/quality. This wave will take a similar track to the previous ones toward the mid MS Valley, to the north of the better moisture. Nonetheless, scattered showers and storms are likely on D5 and into Sunday/D6 from the northern Gulf Coast into the Southeast. Thereafter, high pressure is again forecast over the Plains, with offshore flow developing over the Gulf of Mexico and East Coast Monday/D7 into Tuesday/D8 as the upper trough amplifies over the East. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CST Tue Nov 28 2023 Valid 011200Z - 061200Z ...DISCUSSION... A pair of embedded shortwave troughs within the larger-scale southwesterlies will move across the OH Valley and southern Plains on Friday/D4, as a cold front sinks southward along the northern Gulf Coast. Ongoing showers and thunderstorms will move quickly east across AL/GA, with only weak instability present. Meanwhile, drying behind this lead system will result in little to no instability for the lagging wave over the Plains. On Saturday/D5, another shortwave trough will move into the central/southern Plains, with minimal moisture return/quality. This wave will take a similar track to the previous ones toward the mid MS Valley, to the north of the better moisture. Nonetheless, scattered showers and storms are likely on D5 and into Sunday/D6 from the northern Gulf Coast into the Southeast. Thereafter, high pressure is again forecast over the Plains, with offshore flow developing over the Gulf of Mexico and East Coast Monday/D7 into Tuesday/D8 as the upper trough amplifies over the East. Read more