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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 PM CST Tue Feb 18 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today through tonight. ...West-central coast of FL Peninsula... An organized QLCS is expected to evolve just off the MS River Delta over the north-central Gulf by 12Z this morning. 00Z HREF guidance is consistent in depicting this QLCS moving southeastward along the northern periphery of the Loop Current, with a weakening trend as it progresses across the cooler waters of the northeast Gulf. Remnants of this MCS should reach the west coast of the FL Peninsula, roughly centered on the Tampa Bay area at peak heating in the afternoon. Despite favorable time of day, poor lapse rates above a shallow boundary layer and modest large-scale ascent owing to dampening of the parent low-amplitude shortwave trough should help mitigate an appreciable severe risk. But with an increase in low-level flow accompanying the decaying MCS, locally strong gusts along the immediate coast are possible. ..Grams/Thornton.. 02/19/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1136 PM CST Tue Feb 18 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today through tonight. ...West-central coast of FL Peninsula... An organized QLCS is expected to evolve just off the MS River Delta over the north-central Gulf by 12Z this morning. 00Z HREF guidance is consistent in depicting this QLCS moving southeastward along the northern periphery of the Loop Current, with a weakening trend as it progresses across the cooler waters of the northeast Gulf. Remnants of this MCS should reach the west coast of the FL Peninsula, roughly centered on the Tampa Bay area at peak heating in the afternoon. Despite favorable time of day, poor lapse rates above a shallow boundary layer and modest large-scale ascent owing to dampening of the parent low-amplitude shortwave trough should help mitigate an appreciable severe risk. But with an increase in low-level flow accompanying the decaying MCS, locally strong gusts along the immediate coast are possible. ..Grams/Thornton.. 02/19/2025 Read more

MD 0116 CONCERNING HEAVY SNOW FOR NORTHEASTERN ARKANSAS...SOUTHEASTERN MISSOURI...WESTERN TENNESSEE...WESTERN KENTUCKY...SOUTHERN ILLINOIS
Mesoscale Discussion 0116 NWS Storm Prediction Center Norman OK 0601 PM CST Tue Feb 18 2025 Areas affected...Northeastern Arkansas...Southeastern Missouri...Western Tennessee...Western Kentucky...Southern Illinois Concerning...Heavy snow Valid 190001Z - 190300Z SUMMARY...Snowfall rates will gradually increase across portions of western Kentucky and western Tennessee through the evening. Rates will decrease through time, though some moderate to heavy snowfall rates up to 1"/hr will be possible in heavier bands. DISCUSSION...Radar analysis shows the gradual shift of snowfall into portions of western Kentucky and Tennessee this evening. Moderate to heavy snowfall is ongoing across southeastern Missouri into southern Illinois, where a persistent heavy band extends, driven by 700-850 mb frontogenesis and isentropic ascent. This enhancement will gradually shift eastward through time, with potential for a few heavier bands with occasional 1"/hr rates. HREF ensemble guidance shows a down trend in rates overall through the evening, with a transition to mostly light snow for portions of western Tennessee. Confidence is highest in potential for better rates across northwestern Kentucky into southern Illinois. ..Thornton.. 02/19/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LMK...OHX...PAH...MEG...LSX...LZK... LAT...LON 36199081 37389042 37878993 38068914 37978804 37858767 37538701 37378687 36828672 36458661 35628715 35118774 35078876 35158957 35399041 35479063 35929094 36109086 36199081 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Tue Feb 18 2025 Valid 190100Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Hail should be the primary hazard, but a brief tornado and localized severe gusts may occur along the immediate Louisiana Coast. ...Southeast TX and south LA... Overall forecast scenario appears to be evolving as anticipated. Elevated convection over southeast TX/southwest LA will have the best chance at producing marginally severe hail along the eastern periphery of steeper mid-level lapse rates, sampled upstream by the 00Z FWD sounding. An increasingly predominant cluster convective mode is anticipated with time tonight, limiting the hail threat amid weaker lapse rates with eastern extent across LA. Guidance continues a slightly southward trend to placement of the warm front overnight near the LA coast as weak surface cyclogenesis occurs in the northwest Gulf. With ongoing convection curtailing northward displacement of the stable surface air mass inland, these trends suggest the wind/tornado threats should remain spatially confined along the immediate coast near the MS River Delta. ..Grams.. 02/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Tue Feb 18 2025 Valid 190100Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Hail should be the primary hazard, but a brief tornado and localized severe gusts may occur along the immediate Louisiana Coast. ...Southeast TX and south LA... Overall forecast scenario appears to be evolving as anticipated. Elevated convection over southeast TX/southwest LA will have the best chance at producing marginally severe hail along the eastern periphery of steeper mid-level lapse rates, sampled upstream by the 00Z FWD sounding. An increasingly predominant cluster convective mode is anticipated with time tonight, limiting the hail threat amid weaker lapse rates with eastern extent across LA. Guidance continues a slightly southward trend to placement of the warm front overnight near the LA coast as weak surface cyclogenesis occurs in the northwest Gulf. With ongoing convection curtailing northward displacement of the stable surface air mass inland, these trends suggest the wind/tornado threats should remain spatially confined along the immediate coast near the MS River Delta. ..Grams.. 02/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Tue Feb 18 2025 Valid 190100Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Hail should be the primary hazard, but a brief tornado and localized severe gusts may occur along the immediate Louisiana Coast. ...Southeast TX and south LA... Overall forecast scenario appears to be evolving as anticipated. Elevated convection over southeast TX/southwest LA will have the best chance at producing marginally severe hail along the eastern periphery of steeper mid-level lapse rates, sampled upstream by the 00Z FWD sounding. An increasingly predominant cluster convective mode is anticipated with time tonight, limiting the hail threat amid weaker lapse rates with eastern extent across LA. Guidance continues a slightly southward trend to placement of the warm front overnight near the LA coast as weak surface cyclogenesis occurs in the northwest Gulf. With ongoing convection curtailing northward displacement of the stable surface air mass inland, these trends suggest the wind/tornado threats should remain spatially confined along the immediate coast near the MS River Delta. ..Grams.. 02/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Tue Feb 18 2025 Valid 190100Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Hail should be the primary hazard, but a brief tornado and localized severe gusts may occur along the immediate Louisiana Coast. ...Southeast TX and south LA... Overall forecast scenario appears to be evolving as anticipated. Elevated convection over southeast TX/southwest LA will have the best chance at producing marginally severe hail along the eastern periphery of steeper mid-level lapse rates, sampled upstream by the 00Z FWD sounding. An increasingly predominant cluster convective mode is anticipated with time tonight, limiting the hail threat amid weaker lapse rates with eastern extent across LA. Guidance continues a slightly southward trend to placement of the warm front overnight near the LA coast as weak surface cyclogenesis occurs in the northwest Gulf. With ongoing convection curtailing northward displacement of the stable surface air mass inland, these trends suggest the wind/tornado threats should remain spatially confined along the immediate coast near the MS River Delta. ..Grams.. 02/19/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Tue Feb 18 2025 Valid 190100Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Hail should be the primary hazard, but a brief tornado and localized severe gusts may occur along the immediate Louisiana Coast. ...Southeast TX and south LA... Overall forecast scenario appears to be evolving as anticipated. Elevated convection over southeast TX/southwest LA will have the best chance at producing marginally severe hail along the eastern periphery of steeper mid-level lapse rates, sampled upstream by the 00Z FWD sounding. An increasingly predominant cluster convective mode is anticipated with time tonight, limiting the hail threat amid weaker lapse rates with eastern extent across LA. Guidance continues a slightly southward trend to placement of the warm front overnight near the LA coast as weak surface cyclogenesis occurs in the northwest Gulf. With ongoing convection curtailing northward displacement of the stable surface air mass inland, these trends suggest the wind/tornado threats should remain spatially confined along the immediate coast near the MS River Delta. ..Grams.. 02/19/2025 Read more

No watches are valid as of Tue Feb 18 23:46:02 UTC 2025.

No Mesoscale Discussions are in effect as of Tue Feb 18 23:46:02 UTC 2025.

MD 0114 CONCERNING HEAVY SNOW FOR PORTIONS OF SOUTHEASTERN KS...FAR NORTHEASTERN OK AND THE OZARK PLATEAU
Mesoscale Discussion 0114 NWS Storm Prediction Center Norman OK 1220 PM CST Tue Feb 18 2025 Areas affected...portions of southeastern KS...far northeastern OK and the Ozark Plateau Concerning...Heavy snow Valid 181820Z - 182345Z SUMMARY...Snowfall rates are expected to increase across portions of eastern KS and the Ozarks over the next few hours. Rates of 1-1.5 in/hr are expected within the heavier banding. DISCUSSION...As of 1820 UTC, regional radar and surface observations showed a broad area of winter precipitation ongoing over the Plains and beginning to shift eastward toward the Ozark Plateau. A pronounced band of heavier snow has slowly coalesced over the last couple of hours across portions of southeastern KS and northeastern OK. Likely supported by 850-700 mb frontogenesis and isentropic ascent, heavy snow with rates over 1" per hour have been observed. As ascent from the upstream shortwave trough continues to intensify, so to should the snow band as it gradually shifts eastward into parts of MO and northern AR. Hi-res model guidance and area RAP soundings generally agree with observational trends and suggest strengthening of the band is likely over the next several hours. Very cold low-level temperatures (teens to single digits) will support efficient dendrite generation with snow to liquid ratios in excess of 15:1. Confidence is highest that the heavier rates will occur generally along and south of I-44 across parts of northern AR and southern MO through this evening. ..Lyons.. 02/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LSX...LZK...SGF...EAX...TSA...ICT... LAT...LON 38309384 38089168 37839048 37408956 37318946 36628951 36489018 36119161 36009271 36159440 36839512 37789510 38199456 38309384 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0428 PM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Discussion... In the wake of a cold front exiting the Florida Peninsula, strong surface high pressure (1040+ mb) and an Arctic air mass will settle over much of the CONUS on Thursday. Prevalent cold and stable conditions are expected to considerably limit thunderstorm potential. ..Guyer.. 02/18/2025 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook RESENT 2 NWS Storm Prediction Center Norman OK 0341 PM CST Tue Feb 18 2025 Valid 182000Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHEAST TEXAS INTO SOUTHERN LOUISIANA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across southern Louisiana tonight. Hail should be the primary hazard, but a brief tornado and occasional severe gusts may occur along the immediate Louisiana Coast. ...20Z Update... The previous forecast remains on track. Low-level warm-air and moisture advection are already underway across coastal portions of TX and LA, as indicated by 19Z mesoanalysis. Current thinking is that the low-level warm-air/moisture advection will continue to increase and boost elevated CAPE to 1000 J/kg along the coast with the approach of a mid-level impulse currently situated over NM. Elevated thunderstorms should develop later this evening. Mainly hail is expected given elongated hodographs. However, if any supercellular structure can materialize along the southeast LA coast and become rooted in the boundary layer tonight, a damaging gust or tornado cannot be ruled out. ..Squitieri.. 02/18/2025 .PREV DISCUSSION... /ISSUED 1029 AM CST Tue Feb 18 2025/ ...Southeast Texas into Southern Louisiana... Water-vapor imagery this morning shows a shortwave trough moving into northern AZ from the Great Basin. This upper feature will move east-southeast during the period reaching northern LA/southern AR by daybreak Wednesday. Surface analysis this morning delineates an arctic cold front from the Concho Valley northeastward into north TX. This boundary will continue to surge south-southeastward to the TX coast tonight. A modifying airmass over the northwest Gulf Basin will aid in destabilization this afternoon/evening over southeast TX. Thunderstorms should eventually form by this evening across parts of southeast TX as large-scale ascent increases. Forecast soundings continue to indicate this thunderstorm activity will likely remain elevated with around 1000 J/kg MUCAPE. This activity will spread eastward across portions of southern LA late this evening and overnight while posing mainly an isolated hail threat. The surface-based thunderstorm probabilities are greatest near the south-central and southeast LA coast. However, low-level lapse rates in a deep/saturated environment will be modest, likely limiting tornado potential. Nonetheless, if a couple of storms can become near-surface based in the coastal parishes, a risk for severe gusts may accompany the stronger storms. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook RESENT 2 NWS Storm Prediction Center Norman OK 0341 PM CST Tue Feb 18 2025 Valid 182000Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF SOUTHEAST TEXAS INTO SOUTHERN LOUISIANA... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across parts of southeast Texas, shifting across southern Louisiana tonight. Hail should be the primary hazard, but a brief tornado and occasional severe gusts may occur along the immediate Louisiana Coast. ...20Z Update... The previous forecast remains on track. Low-level warm-air and moisture advection are already underway across coastal portions of TX and LA, as indicated by 19Z mesoanalysis. Current thinking is that the low-level warm-air/moisture advection will continue to increase and boost elevated CAPE to 1000 J/kg along the coast with the approach of a mid-level impulse currently situated over NM. Elevated thunderstorms should develop later this evening. Mainly hail is expected given elongated hodographs. However, if any supercellular structure can materialize along the southeast LA coast and become rooted in the boundary layer tonight, a damaging gust or tornado cannot be ruled out. ..Squitieri.. 02/18/2025 .PREV DISCUSSION... /ISSUED 1029 AM CST Tue Feb 18 2025/ ...Southeast Texas into Southern Louisiana... Water-vapor imagery this morning shows a shortwave trough moving into northern AZ from the Great Basin. This upper feature will move east-southeast during the period reaching northern LA/southern AR by daybreak Wednesday. Surface analysis this morning delineates an arctic cold front from the Concho Valley northeastward into north TX. This boundary will continue to surge south-southeastward to the TX coast tonight. A modifying airmass over the northwest Gulf Basin will aid in destabilization this afternoon/evening over southeast TX. Thunderstorms should eventually form by this evening across parts of southeast TX as large-scale ascent increases. Forecast soundings continue to indicate this thunderstorm activity will likely remain elevated with around 1000 J/kg MUCAPE. This activity will spread eastward across portions of southern LA late this evening and overnight while posing mainly an isolated hail threat. The surface-based thunderstorm probabilities are greatest near the south-central and southeast LA coast. However, low-level lapse rates in a deep/saturated environment will be modest, likely limiting tornado potential. Nonetheless, if a couple of storms can become near-surface based in the coastal parishes, a risk for severe gusts may accompany the stronger storms. Read more