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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 PM CST Mon Dec 25 2023 Valid 260100Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis... A large deep-layer cyclone will become vertically stacked and be centered over the north-central Great Plains through tonight. An occluded cyclone near the IA/MN/NE border will feature a boundary arcing from the Upper Midwest southeastward into OH Valley, with the southern portion of the boundary continuing to progress east as a cold front across the northeast Gulf Coast states tonight. A few widely spaced showers/thunderstorms are possible from GA/SC into the southern Appalachians this evening as well as a low risk for thunderstorm activity across the southern FL Peninsula into the FL Straits. Scant to weak buoyancy sampled by the 00z southeastern U.S. raobs indicates thunderstorms will likely remain weak through tonight. Elsewhere, quiescent conditions will occur in areas displaced from precipitation associated with the deep-layer cyclone over the central U.S., and an approaching shortwave trough over the Pacific Northwest. ..Smith.. 12/26/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 PM CST Mon Dec 25 2023 Valid 260100Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis... A large deep-layer cyclone will become vertically stacked and be centered over the north-central Great Plains through tonight. An occluded cyclone near the IA/MN/NE border will feature a boundary arcing from the Upper Midwest southeastward into OH Valley, with the southern portion of the boundary continuing to progress east as a cold front across the northeast Gulf Coast states tonight. A few widely spaced showers/thunderstorms are possible from GA/SC into the southern Appalachians this evening as well as a low risk for thunderstorm activity across the southern FL Peninsula into the FL Straits. Scant to weak buoyancy sampled by the 00z southeastern U.S. raobs indicates thunderstorms will likely remain weak through tonight. Elsewhere, quiescent conditions will occur in areas displaced from precipitation associated with the deep-layer cyclone over the central U.S., and an approaching shortwave trough over the Pacific Northwest. ..Smith.. 12/26/2023 Read more

No watches are valid as of Mon Dec 25 22:30:02 UTC 2023.

MD 2346 CONCERNING HEAVY SNOW FOR PORTIONS OF SOUTH-CENTRAL NORTH DAKOTA...CENTRAL AND EASTERN SOUTH DAKOTA...AND NORTH CENTRAL NEBRASKA
Mesoscale Discussion 2346 NWS Storm Prediction Center Norman OK 0331 PM CST Mon Dec 25 2023 Areas affected...Portions of South-Central North Dakota...central and eastern South Dakota...and North Central Nebraska Concerning...Heavy snow Valid 252131Z - 260130Z SUMMARY...Moderate to heavy snow possible this evening, with blizzard conditions at times from south-central North Dakota southward into central South Dakota and north-central Nebraska. DISCUSSION...A deep surface low located across western Iowa has begun to occlude this afternoon while bringing warm and moist air across Iowa and Minnesota into the Dakotas. Aloft, a mid-level low is stacked back to the southwest with very cold air being funneled in by strong northwesterly flow across the High Plains into the Central Plains. Areas of moderate to heavy snow have been ongoing across eastern Nebraska and eastern South Dakota, with a transition to accumulating ice/freezing rain to the northeast. Due to the strength of the surface low, background flow has increased with the strong mass response with surface winds sustained at 25-30 mph gusting as high as 40-50 mph. Blizzard conditions have been observed across central South Dakota with visibility around 1/4 mi and sustained winds at 20-30 mph gusting up to 50 mph. As the surface low shifts back westward through the evening, strengthening mid-level flow around 40-50 kts will overspread portions of the Dakotas into western Nebraska. Warm air overspreading eastern North Dakota into northeastern South Dakota will lead to a transition from snow to freezing rain with potential for ice accumulations. The increased upper-level support across the Dakotas into far northern Nebraska will aid in formation of snow bands capable of 1"+/hr rates along with potential for blowing snow and reduced visibility below 1/4 mi with continued strong surface winds. These conditions will continue to spread westward as the low shifts west through the late evening and overnight. ..Thornton/Hart.. 12/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...FSD...ABR...BIS...LBF...UNR... LAT...LON 42480106 43430210 43880217 44520205 45310195 45890125 46919946 47049925 47499717 46689638 46029630 44159761 43679792 43159838 42649882 42239942 42209951 42160028 42480106 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0300 PM CST Mon Dec 25 2023 Valid 271200Z - 021200Z The potential for critical fire-weather conditions is low through the extended forecast period. An expansive midlevel low will move gradually eastward from the Middle MS Valley to the central/southern Appalachians from D3/Wednesday through D5/Friday. Along the southern periphery of this feature, strong deep-layer flow will overspread the Lower MS Valley, Gulf Coast, and Southeast. This will promote locally breezy/gusty offshore flow across these areas, though generally cool surface temperatures will limit RH reductions. While ongoing extreme/exceptional drought suggests fuels may be locally receptive to carrying fires across the region, recent rainfall and the marginal wind/RH combination should limit most fire-weather concerns. Elsewhere across the CONUS, a limited overlap of warm/dry/breezy conditions will mitigate fire-weather potential. ..Weinman.. 12/25/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Mon Dec 25 21:06:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0158 PM CST Mon Dec 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...20Z Update... Thunderstorms have largely been relegated to the Dry Tortugas vicinity this afternoon and may remain west to south of the FL Keys into this evening. Thunder potential over most of the FL Peninsula appears rather limited. Some uptick in weak, elevated convection should occur farther north in the southern Appalachians to Savannah Valley vicinity, with sporadic embedded thunderstorms possible after dusk. Poor near-surface lapse rates in conjunction with the trailing portion of 40+ kt 850-mb flow shifting northeast while shrinking in areal extent, all suggest that severe potential remains negligible. ..Grams.. 12/25/2023 .PREV DISCUSSION... /ISSUED 1021 AM CST Mon Dec 25 2023/ A large upper low dominates the weather across the CONUS today, while the primary weather-making shortwave rotates across the Southeast states and Mid-Atlantic region. Scattered thunderstorms are possible from the central Appalachians southward into FL today, with relatively cool/stable near-surface conditions limiting any risk of severe weather. ...FL Keys... The only area of some minor concern is over the middle and lower FL Keys. Radar/satellite imagery show a cluster of strong thunderstorms about 120nm west of Key West. This activity is moving slowly eastward, and will likely affect the Keys late this afternoon and early evening. However, low-level winds are weakening with time, and CAPE values are strong over the open waters compared to farther east near the Keys. Therefore, the risk of severe storms moving inland appears low. Read more

MD 2345 CONCERNING WINTER MIXED PRECIPITATION FOR EASTERN NEBRASKA...FAR WESTERN IOWA...EASTERN SOUTH DAKOTA...FAR WESTERN MINNESOTA...FAR SOUTHEAST NORTH DAKOTA
Mesoscale Discussion 2345 NWS Storm Prediction Center Norman OK 0700 AM CST Mon Dec 25 2023 Areas affected...Eastern Nebraska...Far Western Iowa...Eastern South Dakota...Far Western Minnesota...Far Southeast North Dakota Concerning...Winter mixed precipitation Valid 251300Z - 251900Z SUMMARY...A mix of freezing rain and sleet will be likely this morning along a narrow corridor from far western Iowa northward into far western Minnesota. Moderate snow, with the possibility of localized heavy snow, will be likely from eastern Nebraska northward across much of east-central South Dakota. DISCUSSION...A mid-level low will steadily deepen across the central High Plains this morning, as a surface low moves northward across central Iowa. A distinct band of large-scale ascent is forecast to move around the northern periphery of the system, making conditions favorable for widespread winter precipitation. Surface temperatures will be in the upper 20s and lower 30s F from near Omaha, Nebraska northward to near Fargo, North Dakota. RAP forecast soundings along this corridor this morning have a warm layer near 850 mb, suggesting that precipitation will be mostly in the form of freezing rain, and possibly sleet. Freezing rain rates of one tenth of an inch per hour will be possible in some areas. Further west from northeast Nebraska northward across much of east-central South Dakota, forecast soundings show sub-freezing temperatures throughout the low levels. This will support moderate snow. As isentropic lift dramatically strengthens this morning, locally heavy snow will be possible in some areas. Snowfall rates could reach near one inch per hour within the heaviest of bands. ..Broyles.. 12/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...DMX...FGF...FSD...OAX...ABR...GID...BIS... LBF... LAT...LON 42069893 41459833 40979733 40909660 41059597 41249549 41619522 42669541 43779580 44409603 45409619 46209610 46769644 46869705 46469784 45749879 44899946 44299968 43179945 42069893 Read more