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SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Wed Jan 22 2025 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast for Friday. ...Synopsis... On Friday, an upper trough will extend from the Great Lakes southwestward into TX, with strong southwest flow aloft from across the Southeast. This trough will be progressive and move off the East Coast by early Saturday, allowing for rising heights/warming aloft across much of the CONUS. Meanwhile, another upper trough will develop southward into parts of the northwestern states. At the surface, substantial cool and/or dry air will remain from the Four Corners states eastward to the Atlantic Coast, with offshore winds over the Gulf of Mexico. Elsewhere, while cooling aloft will occur overnight over the northwest USA, little to no instability is forecast due to cold surface conditions. ..Jewell.. 01/22/2025 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0125 AM CST Wed Jan 22 2025 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast for Friday. ...Synopsis... On Friday, an upper trough will extend from the Great Lakes southwestward into TX, with strong southwest flow aloft from across the Southeast. This trough will be progressive and move off the East Coast by early Saturday, allowing for rising heights/warming aloft across much of the CONUS. Meanwhile, another upper trough will develop southward into parts of the northwestern states. At the surface, substantial cool and/or dry air will remain from the Four Corners states eastward to the Atlantic Coast, with offshore winds over the Gulf of Mexico. Elsewhere, while cooling aloft will occur overnight over the northwest USA, little to no instability is forecast due to cold surface conditions. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1147 PM CST Tue Jan 21 2025 Valid 231200Z - 241200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Thursday. ...Synopsis... A cool and stable pattern will persist on Thursday across the CONUS, with a sprawling area of high pressure stretching from the Great Basin to the East Coast. An elongated, positive-tilt upper trough will extend from Quebec southwestward across the Great Lakes and into the southern High Plains by 00Z, and will move toward the MS Valley into Friday morning. Given high pressure at the surface, and generally dry westerly flow above the stable surface layer over the Southeast, thunderstorms remain unlikely. ..Jewell.. 01/22/2025 Read more

MD 0053 CONCERNING HEAVY SNOW FOR CENTRAL AND EASTERN PORTIONS OF THE CAROLINAS
Mesoscale Discussion 0053 NWS Storm Prediction Center Norman OK 0801 PM CST Tue Jan 21 2025 Areas affected...central and eastern portions of the Carolinas Concerning...Heavy snow Valid 220201Z - 220700Z SUMMARY...Moderate to heavy snow should gradually become widespread through early tonight across portions of the central and eastern Carolinas. DISCUSSION...700 mb warm-air and moisture advection are increasing over central and eastern parts of the Carolinas with the approach of a pronounced 500 mb trough that is traversing the central Appalachians. Beneath the 700 mb moistening, strong surface-850 mb cold-air advection is contributing to further saturation and sensible cooling of the column to support a predominance of snow, which is currently being indicated by surface observations on a widespread basis. Ahead of the upper trough, 700 mb frontogenesis is intensifying, which should support increased snowfall rates. As such, in addition to the transition to snow, 0.5-1.0 inch/hour snowfall rates may develop over the next couple of hours, as also suggested by some of the latest high-resolution guidance runs. ..Squitieri.. 01/22/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...ILM...CHS...CAE...GSP... LAT...LON 31968072 32388112 33088159 33798169 34438124 35427983 35787825 36017695 36227604 35877554 35337562 34927650 34557721 34057805 33607881 32857959 32288042 31968072 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1037 PM CST Tue Jan 21 2025 Valid 221200Z - 231200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Models indicate that mid-level ridging across the far western Canadian Provinces will become suppressed by another short wave perturbation emerging from the upstream mid-latitude Pacific, but not before downstream troughing continues to dig southeast and south of the northern U.S. Rockies. This will reinforce larger scale troughing across much of the interior into eastern United States. Although surface ridging initially across much of the Gulf Coast and Atlantic Seaboard is forecast to weaken, seasonably cold and stable boundary-layer conditions may be slow to moderate. It appears that another expansive surface ridge will build across the Great Basin/Rockies into the Great Plains, with a reinforcing intrusion of arctic air surging through much of the upper Mississippi Valley and northeastern Great Plains, today through 12Z Thursday. ..Kerr.. 01/22/2025 Read more

MD 0052 CONCERNING HEAVY SNOW FOR FAR SOUTHEAST LOUISIANA...FAR SOUTHERN MISSISSIPPI...FAR SOUTHERN ALABAMA...FLORIDA PANHANDLE
Mesoscale Discussion 0052 NWS Storm Prediction Center Norman OK 0452 PM CST Tue Jan 21 2025 Areas affected...Far Southeast Louisiana...Far Southern Mississippi...Far Southern Alabama...Florida Panhandle Concerning...Heavy snow Valid 212252Z - 220445Z SUMMARY...Heavy snow will be likely over the next few hours along parts of the central Gulf Coast from far southeast Louisiana into the Florida Panhandle and southern Alabama. Snowfall rates are expected to exceed 1 inch per hour within the heaviest parts of the band. DISCUSSION...Water vapor imagery shows a mid-level trough from the Ohio Valley extending southwestward into the lower Mississippi Valley. A powerful mid-level jet of 100 to 140 knots is located to the east of the trough, with the exit region of this jet located in the central Gulf Coast region. Widespread precipitation is ongoing beneath this feature (where lift is strong) from far southeast Louisiana east-northeastward into the Florida Panhandle and southern Alabama. Most of the precipitation is in the form of snow, with some reports of heavy snow. The latest model forecasts suggest that a band of strong isentropic ascent will continue to spread eastward across the central Gulf Coast region, making conditions favorable for heavy snow over the next few hours. Snowfall rates are expected to exceed 1 inch per hour in some locations. The potential for heavy snow is expected to continue into early to mid evening over southern Alabama and the Florida Panhandle. Further to the west, snowfall rates should gradually decrease over parts of far southeast Louisiana and southern Mississippi. ..Broyles/Smith.. 01/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TAE...BMX...MOB...LIX... LAT...LON 31968552 31388505 30768485 30258490 29918518 29958587 30098666 30118728 29978839 29728905 29538948 29508972 29708985 29978979 30298952 30718851 31188774 32058650 31968552 Read more

MD 0051 CONCERNING HEAVY SNOW FOR PORTIONS OF SOUTHERN GA AND NORTHERN FL
Mesoscale Discussion 0051 NWS Storm Prediction Center Norman OK 0354 PM CST Tue Jan 21 2025 Areas affected...portions of southern GA and northern FL Concerning...Heavy snow Valid 212154Z - 220400Z SUMMARY...Wintry precipitation to the west and north should gradually expand in coverage and intensity over portions of southern GA and northern FL late this afternoon and evening. An initial wintry mix of snow, sleet and freezing rain will be possible before heavy snow, with rates near 1 in/hr, develops this evening. DISCUSSION...As of 2140 UTC, regional radar analysis showed a broad area of winter precipitation ongoing over much of the northern Gulf Coast and Southeast. A band of moderate snow was also expanding over portions of south-central GA. So far, temperatures have remained above freezing over portions of southern GA and northern FL. Strong cold advection from upstream stations in the mid to low 20s F should support a continued cooling trend through the remainder of the afternoon and into this evening. Columnar cooling will be further aided by rapid moistening as deep-layer ascent increases with the approach of the main precipitation shield. This should result in temperatures falling to near or below freezing in the next couple of hours, concurrent with the onset of precipitation from heavier banding to the north and west. As precipitation rates intensify, an initial wintry mix of sleet and freezing rain will develop from southwest to northeast. This should be followed by a relatively fast transition to all snow from the far eastern FL Panhandle and across southern GA between 23-02z. Strong frontogenetic response in the 850-700 mb layer and rapidly cooling temperatures may support snowfall rates near 1"/hr for a few hours as snow gradually expands northeastward through the evening hours. ..Lyons.. 01/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CHS...CAE...JAX...FFC...TAE... LAT...LON 30088437 30198306 31128159 31988108 32488132 32928181 33008217 32508404 31498515 30518497 30088437 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Tue Jan 21 2025 Valid 220100Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. tonight. ...01Z Update... Generally dry and/or stable conditions prevail across much of the nation. East of the Rockies, downslope warming has contribute to some moderation of temperatures across the northern and central Great Plains. Otherwise, cold surface ridging remains entrenched across the southern Great Plains and Gulf Basin through much of the Atlantic Seaboard and offshore Atlantic waters. The surface front near the shallow leading edge of this air mass did shift back inland across the mid/upper Florida Keys and southeastern Florida coastal areas. However, models indicate that warm/dry layers aloft (evident in 22/00Z observed soundings) will suppress deep convective development rooted within weak boundary-layer instability, before the front advances back across and offshore of coastal areas later tonight, in the wake of a developing frontal wave across the southwestern Atlantic. ..Kerr.. 01/22/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0639 PM CST Tue Jan 21 2025 Valid 220100Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. tonight. ...01Z Update... Generally dry and/or stable conditions prevail across much of the nation. East of the Rockies, downslope warming has contribute to some moderation of temperatures across the northern and central Great Plains. Otherwise, cold surface ridging remains entrenched across the southern Great Plains and Gulf Basin through much of the Atlantic Seaboard and offshore Atlantic waters. The surface front near the shallow leading edge of this air mass did shift back inland across the mid/upper Florida Keys and southeastern Florida coastal areas. However, models indicate that warm/dry layers aloft (evident in 22/00Z observed soundings) will suppress deep convective development rooted within weak boundary-layer instability, before the front advances back across and offshore of coastal areas later tonight, in the wake of a developing frontal wave across the southwestern Atlantic. ..Kerr.. 01/22/2025 Read more