SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Tue Jan 28 2025 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Discussion... Split upper-level flow will persist over the CONUS with a slow-moving southern-stream upper low over the Southwest Deserts and northwest Mexico. In the presence of steep lapse rates, a few lightning flashes will be possible across southern California and northern Arizona through around sunset. No thunderstorms are expected elsewhere as cool/stable conditions prevail. ..Guyer/Squitieri.. 01/28/2025 Read more

MD 0056 CONCERNING HEAVY SNOW FOR THE UPPER MICHIGAN VICINITY
Mesoscale Discussion 0056 NWS Storm Prediction Center Norman OK 0633 AM CST Tue Jan 28 2025 Areas affected...the Upper Michigan vicinity Concerning...Heavy snow Valid 281233Z - 281700Z SUMMARY...A period of heavy snow, at rates on the order of 1-2+ inches per hour, appears possible in a corridor overspreading the central Upper Peninsula of Michigan vicinity by midday. DISCUSSION...Downstream of a low-amplitude short wave perturbation, accompanying an intense (110+ kt at 500 mb) jet streak digging east-southeast of the Canadian Prairies, lower/mid-tropospheric warm advection is overspreading the Upper Midwest into Great Lakes region. Associated forcing for ascent is becoming focused across the southwestern flank of an arctic air mass now entrenched across much of the Great Lakes region, particularly near a zone of strong lower/mid-tropospheric frontogenesis, which is forecast to shift from northwestern Ontario across the western Lake Superior and central Upper Peninsula of Michigan vicinity through 17-18z. Forecast soundings across this region indicate that the sub-freezing thermodynamic profiles are in the process of saturating, ahead of an ongoing band of moderate to heavy snow, which appears likely to be maintained through at least early afternoon. Temperatures appear within a few degrees of -15C through an initially deep layer from lower-levels into the 700-600 mb layer, where conditions will be most conducive to large dendritic ice crystal growth. Coinciding with maximizing lift associated with the frontogenetic forcing, it appears that this may support a 2-3 hour period of heavy snow rates on the order of 1-2 inches per hour. Forecast soundings also indicate that a layer a steepening mid-level lapse rates may be accompanied by the development of weak CAPE and embedded convective development with heavier snow rates possible. ..Kerr.. 01/28/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...APX...MQT...GRB...DLH... LAT...LON 48538911 47918791 46888619 46278519 45418590 44838674 45668731 46428796 46938875 47878969 48538911 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 28 2025 Valid 281300Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Synopsis... Water-vapor imagery loop indicates a split flow upper-air pattern over North America with a closed mid- to upper-level low meandering over the Desert Southwest. A few showers associated with the upper low may become convectively augmented and yield a couple of lightning flashes. Otherwise, docile conditions will prevail across the remainder of the Lower 48 from a thunderstorm perspective. Deep, cyclonic flow will encompass the Upper Midwest southeastward into the Appalachians/Eastern Seaboard and maintain seasonably cool/stable air via continental trajectories. ..Smith/Kerr.. 01/28/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Tue Jan 28 2025 Valid 311200Z - 051200Z ...DISCUSSION... Models forecast steady eastward progression of a cold front across the Southeast and Mid-Atlantic region Day 4/Friday, as a mid-level low devolves into a fast-moving open wave that is expected to cross the Appalachians Friday night, exiting the East Coast states prior to the start of the Day 5 period. While non-zero severe potential will likely exist ahead of the cold front across southern portions of the central Gulf Coast states, it appears at this time that instability will remain meager at best, limiting overall severe potential. After the front moves offshore, lingering only across the Florida Peninsula Day 5/Saturday, severe weather is not expected. Models begin to diverge Day 6/Sunday, with the GFS maintaining a low-amplitude, quasi-zonal flow regime through much of the remainder of the period. While the ECMWF undergoes a gradual trend of slightly greater amplification toward more pronounced eastern U.S. troughing and central U.S. ridging, prevalence of surface high pressure/cold continental air east of the Rockies precludes severe potential through the end of the period. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Tue Jan 28 2025 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN TEXAS INTO WESTERN MISSISSIPPI... ...SUMMARY... Strong/isolated severe storms will be possible Thursday from eastern Texas eastward across the Lower Mississippi Valley. ...Synopsis... An upper low initially forecast to lie over the central/southern High Plains area will shift eastward across Kansas/Oklahoma Thursday, and across the Ozarks Thursday night. As this occurs, a weak surface low is forecast to evolve/shift north-northeastward out of northeastern Texas into Arkansas during the first half of the period, and then on northeastward to Illinois overnight. A trailing front will shift eastward out of eastern Texas into Arkansas/Louisiana with time, and then across the Lower Mississippi Valley to the Lower Ohio and Tennessee Valleys and central Gulf Coast states through the end of the period. ...East Texas to Mississippi... As the surface low shifts north-northeastward with time, and a cold front begins to advance eastward, persistent southerly low-level flow will advect partially modified Gulf air northward into southeastern Texas and Louisiana. Though lapse rates will remain weak, low-level moistening should be sufficient to allow very weak/tall/skinny surface-based CAPE to develop ahead of the advancing front. Elevated convection should be ongoing at the start of the period, moving out of the Hill Country and into East Texas. As the low-level moistening gradually allows storms to become surface-based, potential for damaging winds and a couple of tornadoes will increase through the afternoon, likely maximizing during the early evening hours and expanding into/across Louisiana. Despite the weak CAPE which should hinder the overall risk, very favorable low-level and deep-layer shear will characterize the warm sector, with southerlies increasing and veering substantially with height through the lower half of the troposphere. The main storm mode is expected to be rotating storms embedded within linear bands, spreading eastward across the Lower Mississippi Valley through the evening before weakening overnight ..Goss.. 01/28/2025 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Tue Jan 28 2025 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN TEXAS INTO WESTERN MISSISSIPPI... ...SUMMARY... Strong/isolated severe storms will be possible Thursday from eastern Texas eastward across the Lower Mississippi Valley. ...Synopsis... An upper low initially forecast to lie over the central/southern High Plains area will shift eastward across Kansas/Oklahoma Thursday, and across the Ozarks Thursday night. As this occurs, a weak surface low is forecast to evolve/shift north-northeastward out of northeastern Texas into Arkansas during the first half of the period, and then on northeastward to Illinois overnight. A trailing front will shift eastward out of eastern Texas into Arkansas/Louisiana with time, and then across the Lower Mississippi Valley to the Lower Ohio and Tennessee Valleys and central Gulf Coast states through the end of the period. ...East Texas to Mississippi... As the surface low shifts north-northeastward with time, and a cold front begins to advance eastward, persistent southerly low-level flow will advect partially modified Gulf air northward into southeastern Texas and Louisiana. Though lapse rates will remain weak, low-level moistening should be sufficient to allow very weak/tall/skinny surface-based CAPE to develop ahead of the advancing front. Elevated convection should be ongoing at the start of the period, moving out of the Hill Country and into East Texas. As the low-level moistening gradually allows storms to become surface-based, potential for damaging winds and a couple of tornadoes will increase through the afternoon, likely maximizing during the early evening hours and expanding into/across Louisiana. Despite the weak CAPE which should hinder the overall risk, very favorable low-level and deep-layer shear will characterize the warm sector, with southerlies increasing and veering substantially with height through the lower half of the troposphere. The main storm mode is expected to be rotating storms embedded within linear bands, spreading eastward across the Lower Mississippi Valley through the evening before weakening overnight ..Goss.. 01/28/2025 Read more

MD 0055 CONCERNING SNOW SQUALL FOR NORTH AND WESTERN NEW YORK
Mesoscale Discussion 0055 NWS Storm Prediction Center Norman OK 1223 AM CST Tue Jan 28 2025 Areas affected...North and western New York Concerning...Snow Squall Valid 280623Z - 281130Z SUMMARY...Brief, but intense, snow showers along a strong cold front will move into northern and western New York through the overnight hours. Ahead of the front, heavy snowfall rates up to 1-2 inches/hour are possible along the northeastern shores of the Lower Great Lakes. DISCUSSION...A strong cold front, evident by a pronounced leading band of heavy snow showers, has been pushing southeast out of Ontario/Quebec over the past several hours. Higher reflectivity values (up to 30 dBz) and occasional lightning flashes have been noted along portions of the front, indicative of the deep convective nature of the snow bands. Wind gusts upwards of 20-25 mph have also been noted with the passage of the front across Ontario/Quebec, as well as occasional visibility reductions. Similar conditions are possible as the snow bands cross the Lower Great Lakes and move into northern and western NY. A combination of rapidly falling temperatures along/behind the front, bursts of heavy snow within the stronger bands, and winds gusting up to 25 mph will support snow squall conditions across northern/western NY, and possibly into central NY, over the next several hours. Prior to the passage of the front, southwesterly winds oriented along Lake Erie and Lake Ontario will continue to support moderate to heavy lake effect snow bands on the northeastern shores of both lakes. Recent surface observations have reported visibility reductions between 1/4 to 3/4 of a mile. Despite 20-30 mph winds, blowing snow model output suggests that these visibility reductions are attributable to moderate to heavy snowfall rates. Recent guidance supports this idea and hints that rates up to 1-2 inches/hour are possible prior to the passage of the front. ..Moore.. 01/28/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BTV...ALY...BGM...BUF...CTP...CLE... LAT...LON 42287757 42067847 41987899 41977948 42047976 42197993 42337993 42407972 42617936 42877914 43097911 43237913 43387891 43517827 43417754 43457705 43567674 43827654 44107653 44357633 44807553 45007507 45067476 45077399 45067354 45037338 44897327 44657319 44427333 44217352 43997380 43697430 42337741 42287757 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0146 AM CST Tue Jan 28 2025 Valid 291200Z - 301200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be limited for Wednesday across the country. The upper low currently over western Arizona will shift into the southern Plains through Wednesday evening. Widespread rain chances will overspread the southern Plains and Southwest regions through the day limiting fire weather potential for most areas. One exception is West Texas and south-central NM where rainfall should be limited. While breezy southwest winds are likely, recent guidance suggests the probability of reaching elevated RH thresholds is low. Elsewhere across the country, cool temperatures, weak winds, and/or recent rain/snowfall preclude fire weather concerns. ..Moore.. 01/28/2025 ...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 0146 AM CST Tue Jan 28 2025 Valid 291200Z - 301200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns are expected to be limited for Wednesday across the country. The upper low currently over western Arizona will shift into the southern Plains through Wednesday evening. Widespread rain chances will overspread the southern Plains and Southwest regions through the day limiting fire weather potential for most areas. One exception is West Texas and south-central NM where rainfall should be limited. While breezy southwest winds are likely, recent guidance suggests the probability of reaching elevated RH thresholds is low. Elsewhere across the country, cool temperatures, weak winds, and/or recent rain/snowfall preclude fire weather concerns. ..Moore.. 01/28/2025 ...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 0107 AM CST Tue Jan 28 2025 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns appear limited for today across the country, though localized elevated conditions may emerge across parts of the central Plains and southwest New Mexico. Early-morning water vapor imagery depicts a de-amplifying upper low over western AZ. This feature is expected to meander east through the day, resulting in modest surface pressure falls across western NM and maintaining 30-40 knot mid-level winds over the region. While pressure gradient winds are expected to be modest (10-15 mph) diurnal heating of a very dry low-level air mass (well sampled by the 00 UTC EPZ sounding) will support deep mixing and downward momentum transfer of the stronger mid-level winds, manifesting as 20-30 mph gusts at the surface. With afternoon RH minimums in the teens expected again for today, localized elevated fire weather conditions may emerge across southwest NM where these stronger gusts are most likely to occur based on recent ensemble guidance. Across the Plains, a clipper low moving southeastward out of the Canadian Prairies will maintain a moderate pressure gradient over the central to northern Plains. Winds between 15-20 mph are expected, with some RH reductions into the 20-35% range possible as a dry air mass (currently upstream over the High Plains) overspreads the region. Confidence in sustained/widespread elevated conditions remains limited, and fuels remain only modestly dry. These concerns preclude highlights at this time, but localized elevated conditions are possible across portions of NE and SD. ..Moore.. 01/28/2025 ...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 0107 AM CST Tue Jan 28 2025 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns appear limited for today across the country, though localized elevated conditions may emerge across parts of the central Plains and southwest New Mexico. Early-morning water vapor imagery depicts a de-amplifying upper low over western AZ. This feature is expected to meander east through the day, resulting in modest surface pressure falls across western NM and maintaining 30-40 knot mid-level winds over the region. While pressure gradient winds are expected to be modest (10-15 mph) diurnal heating of a very dry low-level air mass (well sampled by the 00 UTC EPZ sounding) will support deep mixing and downward momentum transfer of the stronger mid-level winds, manifesting as 20-30 mph gusts at the surface. With afternoon RH minimums in the teens expected again for today, localized elevated fire weather conditions may emerge across southwest NM where these stronger gusts are most likely to occur based on recent ensemble guidance. Across the Plains, a clipper low moving southeastward out of the Canadian Prairies will maintain a moderate pressure gradient over the central to northern Plains. Winds between 15-20 mph are expected, with some RH reductions into the 20-35% range possible as a dry air mass (currently upstream over the High Plains) overspreads the region. Confidence in sustained/widespread elevated conditions remains limited, and fuels remain only modestly dry. These concerns preclude highlights at this time, but localized elevated conditions are possible across portions of NE and SD. ..Moore.. 01/28/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CST Tue Jan 28 2025 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL TEXAS VICINITY... ...SUMMARY... A few strong/possibly severe storms will be possible across parts of the southern Plains Wednesday evening/overnight. ...Synopsis... A closed mid-level low over Arizona early Wednesday will move eastward and then northeastward across the Southwest/southern Rockies, with strong mid-level southwesterlies spreading into the south-central U.S. ahead of this system. At the surface, weak pressure falls across the southern Plains in response to the approach of the upper system will lead to the development of an inverted trough over central Texas through the second half of the period. A broad zone of low-level warm advection/quasigeostrophic forcing for ascent will result in mainly elevated convective development through the second half of the period. ...Central Texas... Low-level theta-e advection will increase through the day Wednesday atop a cool surface-based airmass will result in gradual/weak elevated destabilization. As quasigeostrophic ascent likewise increases with time, elevated showers -- and eventually, scattered thunderstorms -- are expected, with most of the thunderstorm activity to occur after dark. While the greatest low-level moisture (limited to low 60s dewpoints) will occur over eastern portions of central Texas (the Hill Country region), truly surface-based convection appears a low-probability occurrence. Overall, expect convection to be elevated above a persistently stable surface layer, with any wind risk or brief tornado potential limited to eastern portions of the risk area. Otherwise, a few storms capable of producing marginal hail are expected, but overall risk should remain limited by modest CAPE. ..Goss.. 01/28/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CST Tue Jan 28 2025 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL TEXAS VICINITY... ...SUMMARY... A few strong/possibly severe storms will be possible across parts of the southern Plains Wednesday evening/overnight. ...Synopsis... A closed mid-level low over Arizona early Wednesday will move eastward and then northeastward across the Southwest/southern Rockies, with strong mid-level southwesterlies spreading into the south-central U.S. ahead of this system. At the surface, weak pressure falls across the southern Plains in response to the approach of the upper system will lead to the development of an inverted trough over central Texas through the second half of the period. A broad zone of low-level warm advection/quasigeostrophic forcing for ascent will result in mainly elevated convective development through the second half of the period. ...Central Texas... Low-level theta-e advection will increase through the day Wednesday atop a cool surface-based airmass will result in gradual/weak elevated destabilization. As quasigeostrophic ascent likewise increases with time, elevated showers -- and eventually, scattered thunderstorms -- are expected, with most of the thunderstorm activity to occur after dark. While the greatest low-level moisture (limited to low 60s dewpoints) will occur over eastern portions of central Texas (the Hill Country region), truly surface-based convection appears a low-probability occurrence. Overall, expect convection to be elevated above a persistently stable surface layer, with any wind risk or brief tornado potential limited to eastern portions of the risk area. Otherwise, a few storms capable of producing marginal hail are expected, but overall risk should remain limited by modest CAPE. ..Goss.. 01/28/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1139 PM CST Mon Jan 27 2025 Valid 281200Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may affect northwest Arizona on Tuesday. ...Discussion... A dry and cool airmass will prevail across the CONUS on Tuesday. This will result in minimal thunderstorm activity. The only exception will be across northern Arizona where cold air aloft and steep lapse rates may result in some weak instability sufficient for a few lightning flashes. ..Bentley.. 01/28/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0635 PM CST Mon Jan 27 2025 Valid 280100Z - 281200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential will remain very low through tonight. ...Synopsis... Thunderstorm activity through late afternoon/early evening has been focused across western AZ under an upper low where very cold temperatures aloft, combined with modest low-level warming, has supported sufficient buoyancy for lightning production. This environment was sampled well by the 00 UTC FGZ sounding; however, buoyancy is expected to quickly diminish as surface temperatures rapidly cool with the loss of daytime heating. Falling LightningCast probability values over the past 30-60 minutes suggest this trend is already underway. While a flash or two appears possible during the 01-02 UTC time frame, lightning potential through the remainder of the overnight hours appears sufficiently low to remove thunder probabilities. ..Moore.. 01/28/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0635 PM CST Mon Jan 27 2025 Valid 280100Z - 281200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential will remain very low through tonight. ...Synopsis... Thunderstorm activity through late afternoon/early evening has been focused across western AZ under an upper low where very cold temperatures aloft, combined with modest low-level warming, has supported sufficient buoyancy for lightning production. This environment was sampled well by the 00 UTC FGZ sounding; however, buoyancy is expected to quickly diminish as surface temperatures rapidly cool with the loss of daytime heating. Falling LightningCast probability values over the past 30-60 minutes suggest this trend is already underway. While a flash or two appears possible during the 01-02 UTC time frame, lightning potential through the remainder of the overnight hours appears sufficiently low to remove thunder probabilities. ..Moore.. 01/28/2025 Read more

No Mesoscale Discussions are in effect as of Mon Jan 27 22:01:02 UTC 2025.

No watches are valid as of Mon Jan 27 22:01:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0347 PM CST Mon Jan 27 2025 Valid 291200Z - 041200Z Fire weather concerns will remain low in the early part of the extended forecast. An upper-low that has remained over the western US will eject across the southern Rockies into the Plains D3/Wednesday through D4/Thursday, bringing windy conditions but also chances for precipitation. Towards the weekend, potential for windy/dry conditions will exist across portions of the High Plains and Southern Plains as enhanced upper-level flow moves across the Rockies. A surface cyclone will develop across the southern Plains, with strengthening of a lee trough across the High Plains. This pattern will favor periods of elevated fire-weather conditions, particularly across southwestern and western Texas where freeze cured grasses may support risk for fire spread. Elsewhere, marginal fuels and chances for additional precipitation should limit the potential for critical conditions. ..Thornton.. 01/27/2025 ...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 0347 PM CST Mon Jan 27 2025 Valid 291200Z - 041200Z Fire weather concerns will remain low in the early part of the extended forecast. An upper-low that has remained over the western US will eject across the southern Rockies into the Plains D3/Wednesday through D4/Thursday, bringing windy conditions but also chances for precipitation. Towards the weekend, potential for windy/dry conditions will exist across portions of the High Plains and Southern Plains as enhanced upper-level flow moves across the Rockies. A surface cyclone will develop across the southern Plains, with strengthening of a lee trough across the High Plains. This pattern will favor periods of elevated fire-weather conditions, particularly across southwestern and western Texas where freeze cured grasses may support risk for fire spread. Elsewhere, marginal fuels and chances for additional precipitation should limit the potential for critical conditions. ..Thornton.. 01/27/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more