Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Mon Feb 27 2023 Valid 271630Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing a few tornadoes and damaging gusts will be possible across the Ohio Valley today, especially across parts of Indiana and Ohio through this afternoon. ...Ohio Valley... A compact shortwave trough with an associated pocket of cold mid-level temperatures (around -18 to -20C at 500 mb) will advance quickly east-northeastward over the OH Valley and Great Lakes region today. At the surface, a low will gradually occlude as it develops eastward over northern IL, southern Lower MI, and vicinity through this evening. Pronounced low/mid-level flow strengthens and veers with height per recent area VWPs, with plentiful low-level shear to support updraft rotation. While instability should remain fairly weak owing to modest low-level moisture along/south of a warm front, visible satellite imagery shows some clearing occurring across eastern IL into IN this morning. RAP forecast soundings suggest that as surface temperatures warm into the 60s amid mid to upper 50s dewpoints, resultant 250-600 J/kg MLCAPE should support surface-based convection. A 50-60+ kt low-level jet, with flow quickly veering to southwesterly above that through mid levels, is aiding enlarged hodographs across the gradually destabilizing warm sector, with effective SRH of 200-300+ m2/s2 likely along/south of the surface front. A couple of tornadoes have already occurred this morning associated with a low-topped supercell in east-central IL. As additional low-topped storms develop over the next couple of hours and spread eastward into parts of northern/central IN, threat for a few tornadoes should continue given the plentiful low-level shear. Isolated damaging winds may also occur with any small bowing segments. Sufficient low-level moisture to support surface-based convection will attempt to advance northward into parts of OH this afternoon as well. Some tornado and damaging wind threat should continue across OH if this occurs, as the enhanced wind fields attendant to the low-level jet and mid-level shortwave trough shift quickly eastward across the OH Valley. These low-topped cells will eventually outpace the low-level moisture return and surface-based instability by this evening, with a lessening severe threat with eastward extent into PA/WV. ..Gleason/Wendt.. 02/27/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Mon Feb 27 2023 Valid 271630Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing a few tornadoes and damaging gusts will be possible across the Ohio Valley today, especially across parts of Indiana and Ohio through this afternoon. ...Ohio Valley... A compact shortwave trough with an associated pocket of cold mid-level temperatures (around -18 to -20C at 500 mb) will advance quickly east-northeastward over the OH Valley and Great Lakes region today. At the surface, a low will gradually occlude as it develops eastward over northern IL, southern Lower MI, and vicinity through this evening. Pronounced low/mid-level flow strengthens and veers with height per recent area VWPs, with plentiful low-level shear to support updraft rotation. While instability should remain fairly weak owing to modest low-level moisture along/south of a warm front, visible satellite imagery shows some clearing occurring across eastern IL into IN this morning. RAP forecast soundings suggest that as surface temperatures warm into the 60s amid mid to upper 50s dewpoints, resultant 250-600 J/kg MLCAPE should support surface-based convection. A 50-60+ kt low-level jet, with flow quickly veering to southwesterly above that through mid levels, is aiding enlarged hodographs across the gradually destabilizing warm sector, with effective SRH of 200-300+ m2/s2 likely along/south of the surface front. A couple of tornadoes have already occurred this morning associated with a low-topped supercell in east-central IL. As additional low-topped storms develop over the next couple of hours and spread eastward into parts of northern/central IN, threat for a few tornadoes should continue given the plentiful low-level shear. Isolated damaging winds may also occur with any small bowing segments. Sufficient low-level moisture to support surface-based convection will attempt to advance northward into parts of OH this afternoon as well. Some tornado and damaging wind threat should continue across OH if this occurs, as the enhanced wind fields attendant to the low-level jet and mid-level shortwave trough shift quickly eastward across the OH Valley. These low-topped cells will eventually outpace the low-level moisture return and surface-based instability by this evening, with a lessening severe threat with eastward extent into PA/WV. ..Gleason/Wendt.. 02/27/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Mon Feb 27 2023 Valid 271630Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing a few tornadoes and damaging gusts will be possible across the Ohio Valley today, especially across parts of Indiana and Ohio through this afternoon. ...Ohio Valley... A compact shortwave trough with an associated pocket of cold mid-level temperatures (around -18 to -20C at 500 mb) will advance quickly east-northeastward over the OH Valley and Great Lakes region today. At the surface, a low will gradually occlude as it develops eastward over northern IL, southern Lower MI, and vicinity through this evening. Pronounced low/mid-level flow strengthens and veers with height per recent area VWPs, with plentiful low-level shear to support updraft rotation. While instability should remain fairly weak owing to modest low-level moisture along/south of a warm front, visible satellite imagery shows some clearing occurring across eastern IL into IN this morning. RAP forecast soundings suggest that as surface temperatures warm into the 60s amid mid to upper 50s dewpoints, resultant 250-600 J/kg MLCAPE should support surface-based convection. A 50-60+ kt low-level jet, with flow quickly veering to southwesterly above that through mid levels, is aiding enlarged hodographs across the gradually destabilizing warm sector, with effective SRH of 200-300+ m2/s2 likely along/south of the surface front. A couple of tornadoes have already occurred this morning associated with a low-topped supercell in east-central IL. As additional low-topped storms develop over the next couple of hours and spread eastward into parts of northern/central IN, threat for a few tornadoes should continue given the plentiful low-level shear. Isolated damaging winds may also occur with any small bowing segments. Sufficient low-level moisture to support surface-based convection will attempt to advance northward into parts of OH this afternoon as well. Some tornado and damaging wind threat should continue across OH if this occurs, as the enhanced wind fields attendant to the low-level jet and mid-level shortwave trough shift quickly eastward across the OH Valley. These low-topped cells will eventually outpace the low-level moisture return and surface-based instability by this evening, with a lessening severe threat with eastward extent into PA/WV. ..Gleason/Wendt.. 02/27/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1026 AM CST Mon Feb 27 2023 Valid 271630Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing a few tornadoes and damaging gusts will be possible across the Ohio Valley today, especially across parts of Indiana and Ohio through this afternoon. ...Ohio Valley... A compact shortwave trough with an associated pocket of cold mid-level temperatures (around -18 to -20C at 500 mb) will advance quickly east-northeastward over the OH Valley and Great Lakes region today. At the surface, a low will gradually occlude as it develops eastward over northern IL, southern Lower MI, and vicinity through this evening. Pronounced low/mid-level flow strengthens and veers with height per recent area VWPs, with plentiful low-level shear to support updraft rotation. While instability should remain fairly weak owing to modest low-level moisture along/south of a warm front, visible satellite imagery shows some clearing occurring across eastern IL into IN this morning. RAP forecast soundings suggest that as surface temperatures warm into the 60s amid mid to upper 50s dewpoints, resultant 250-600 J/kg MLCAPE should support surface-based convection. A 50-60+ kt low-level jet, with flow quickly veering to southwesterly above that through mid levels, is aiding enlarged hodographs across the gradually destabilizing warm sector, with effective SRH of 200-300+ m2/s2 likely along/south of the surface front. A couple of tornadoes have already occurred this morning associated with a low-topped supercell in east-central IL. As additional low-topped storms develop over the next couple of hours and spread eastward into parts of northern/central IN, threat for a few tornadoes should continue given the plentiful low-level shear. Isolated damaging winds may also occur with any small bowing segments. Sufficient low-level moisture to support surface-based convection will attempt to advance northward into parts of OH this afternoon as well. Some tornado and damaging wind threat should continue across OH if this occurs, as the enhanced wind fields attendant to the low-level jet and mid-level shortwave trough shift quickly eastward across the OH Valley. These low-topped cells will eventually outpace the low-level moisture return and surface-based instability by this evening, with a lessening severe threat with eastward extent into PA/WV. ..Gleason/Wendt.. 02/27/2023 Read more

WW 0042 Status Updates
STATUS FOR WATCH 0042 HAS NOT BEEN ISSUED YET Read more

MD 0189 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR SOUTHWEST KS...EASTERN TX/OK PANHANDLES...WESTERN OK
Mesoscale Discussion 0189 NWS Storm Prediction Center Norman OK 0233 PM CST Sun Feb 26 2023 Areas affected...Southwest KS...Eastern TX/OK Panhandles...Western OK Concerning...Severe potential...Tornado Watch likely Valid 262033Z - 262230Z Probability of Watch Issuance...80 percent SUMMARY...Fast-moving supercells capable of all severe hazards, including significant wind gusts over 80 mph, very large hail greater than 2 inches in diameter, and tornadoes, are expected to develop across the region this afternoon and evening. A Tornado Watch will be needed within the next hour or two. DISCUSSION...Significant air mass modification continues across the southern Plains ahead of an intense upper low moving out of the Southwest. Much of the eastern TX and OK Panhandles and western OK have experienced dewpoint increases of 4 to 8 deg F over the past 3 hours. This modification is expected to continue as large-scale forcing for ascent attendant to the approaching low increases, likely resulting in thunderstorm initiation during the next hour or two from southwest KS across the eastern OK and TX Panhandles and into northwest TX. Wind fields, which are already quite strong, are expected to further strengthen as the system approaches. Current mesoanalysis estimates the 0-6 km shear is already 70 kt, with forecast soundings suggesting an increase to 85-90 kt is anticipated by 00Z. Forecast hodographs also show robust low veering with height, supported by 50-60 kt flow around 1 km. Forecast soundings show surface to 500 m storm-relative helicity is over 300 m2/s2 across the eastern TX and OK Panhandles at 00Z. These environmental conditions are very supportive of supercells capable of all severe hazards, including significant wind gusts over 80 mph, very large hail greater than 2 inches in diameter, and tornadoes. Upscale growth into a linear convective line is anticipated, with strong wind gusts and embedded tornadoes possible once this transition occurs. A Tornado Watch will be needed in the next hour or two to cover this potential. ..Mosier/Grams.. 02/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...DDC...LUB...AMA... LAT...LON 36030178 37260160 37710105 37660023 37079977 36179954 33759956 33150058 33410134 34080164 36030178 Read more

WW 42 SEVERE TSTM KS 262120Z - 270200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 42 NWS Storm Prediction Center Norman OK 320 PM CST Sun Feb 26 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southwest Kansas * Effective this Sunday afternoon and evening from 320 PM until 800 PM CST. * Primary threats include... Scattered damaging winds and isolated significant gusts to 80 mph possible A tornado or two possible SUMMARY...High-based thunderstorms will spread rapidly northeast across southwest Kansas. Initially well-mixed thermodynamic profiles will support severe wind gusts as the primary hazard. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 75 miles north northeast of Dodge City KS to 25 miles south southwest of Dodge City KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU2). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 400. Mean storm motion vector 22050. ...Grams Read more

MD 0190 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR SOUTHWEST/CENTRAL KS
Mesoscale Discussion 0190 NWS Storm Prediction Center Norman OK 0303 PM CST Sun Feb 26 2023 Areas affected...Southwest/Central KS Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 262103Z - 262300Z Probability of Watch Issuance...80 percent SUMMARY...A line of severe thunderstorms capable of strong wind gusts is expected to develop over the next few hours across southwest KS. A Severe Thunderstorm Watch will likely be needed for portion of the region. DISCUSSION...Surface temperatures have warmed into the mid to upper 70s across southwest KS, while dewpoints currently remain in the upper 30s. Low-level moisture advection is expected to persist for at least the next few hours ahead of the strong shortwave trough moving out the southern High Plains. Even so, dewpoints will likely only reach the upper 40s before the surface low associated with the shortwave moves through. Despite modest thermodynamics, very strong large-scale forcing for ascent augmented by mesoscale ascent near the deepening surface low is still expected to result enough lift to overcome any convective inhibition. A linear storm mode is anticipated, with robust wind fields contributing to the potential for fast-storm motion and strong wind gusts. Given this potential for strong wind gusts, a Severe Thunderstorm Watch will likely be needed for portion of the region. ..Mosier/Grams.. 02/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ICT...DDC... LAT...LON 37450197 37890174 38490057 38899957 38979866 38389844 37949876 37460041 37380115 37450197 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Sun Feb 26 2023 Valid 262000Z - 271200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM THE EASTERN TEXAS PANHANDLE ACROSS MUCH OF OKLAHOMA... ...SUMMARY... A derecho is forecast with widespread damaging winds and embedded swaths of significant severe gusts from 80-110 mph, centered on parts of Oklahoma this evening into tonight. Embedded tornadoes are anticipated as well, with the greatest potential for strong (EF2-EF3) tornadoes across southwest Oklahoma this evening. ...20Z Update... Primary minor changes to the outlook include expanding the significant tornado probabilities a bit northeast toward north-central Oklahoma, and to include an additional portion of the far eastern Texas Panhandle in the Moderate Risk area. Visible imagery as well as surface observations indicate rapid changes are underway across the region with continued thinning/erosion of the low-level clouds over northwest Texas and southwest Oklahoma, and widespread severe wind gusts across New Mexico ahead of the upper trough. Initial storms are likely to form from southwest Kansas into the Texas Panhandle between 21-00Z, with damaging winds, large hail, and tornadoes as dewpoints rise further. Cells will likely merge into a linear MCS/Derecho, producing gusts over 80 mph and isolated tornadoes across Oklahoma this evening. Strong forcing along the front should counteract convective inhibition, with severe wind both within the line and possibly behind it as post-frontal boundary-layer mixing persists. ..Jewell.. 02/26/2023 .PREV DISCUSSION... /ISSUED 1029 AM CST Sun Feb 26 2023/ ...Southern Great Plains to the Mid-MS Valley... Just-in-time moisture return from the western Gulf is still anticipated ahead of a powerful shortwave trough ejecting from the Southwest to the Lower MO Valley. 60+ F surface dew points remain confined from the Piney Woods of east TX to the Concho Valley and Edwards Plateau of west TX as of 16Z. Guidance continues to differ with the northern extent of this richer moisture by evening in KS/OK beneath a stout elevated mixed layer. Widespread cloudiness is also evident over much of the southern Great Plains, although clearing should occur from west to east across the High Plains. The net result should be a narrow plume of surface-based instability along the dryline from southwest KS to west TX between 21-00Z. Scattered convection will break out after 21Z along the dryline and become supercellular towards 00Z given very favorably enlarged low to mid-level hodographs. Further moistening into the evening should result in the most favorable potential for supercell tornadoes in southwest OK between 00-03Z, in addition to very large hail. Convection will likely grow quickly upscale into a solid QLCS, accelerating east-northeast with embedded supercells and mesovortices. Extreme low-level shear profiles in conjunction with strengthening of 700-mb winds to around 90 kts behind the line should result in widespread severe wind gusts. Embedded swaths of 80-110 mph winds both straightline and rotating are likely, with stronger speeds into the EF2 range possible, until the QLCS outpaces the richer moisture in the OK/KS/MO border area overnight. Scattered damaging winds from strong to severe gusts may linger through the early morning across MO towards the Mid-MS Valley, despite little to no buoyancy, given the intense low-level wind fields. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 PM CST Sun Feb 26 2023 Valid 271200Z - 281200Z The previous forecast (see below) for the southern High Plains remains on track, where an expansive area of elevated to near-critical conditions are expected. While locally elevated conditions are also possible farther north into southern CO along the I-25 corridor (especially in gap-flow areas), these conditions appear too localized for highlights. Farther east, 10-15 mph west-southwesterly surface winds could overlap areas of 35-40 percent RH across parts of inland and eastern FL during the afternoon. However, any Elevated conditions should be brief/localized. ..Weinman.. 02/26/2023 .PREV DISCUSSION... /ISSUED 1144 PM CST Sat Feb 25 2023/ ...Synopsis... Relatively zonal mid-level flow will prevail across the Southern Plains tomorrow/Monday in the wake of a passing mid-level trough. Deep-layer westerly flow will continue to promote dry and windy downslope conditions across the southern High Plains. By afternoon peak heating, widespread 15-20 percent RH will overlap with 20+ mph sustained westerly surface winds across eastern New Mexico into western Texas. Given at least marginally receptive fine fuels, Elevated highlights have been introduced where a consensus among the latest guidance members is greatest in terms of where the most favorable winds/RH will overlap. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1034 AM CST SUN FEB 26 2023 ...Severe thunderstorms expected over parts of the southern Plains this evening into tonight... * LOCATIONS... Western, central, and northern Oklahoma Far northwest Texas * HAZARDS... Widespread damaging winds, some hurricane force A few intense tornadoes Isolated large hail up to baseball size * SUMMARY... A derecho is forecast with widespread damaging winds and embedded swaths of significant severe gusts from 80-110 mph, centered on parts of Oklahoma this evening into tonight. Embedded tornadoes are anticipated as well, with the greatest potential for strong (EF2-EF3) tornadoes across southwest Oklahoma this evening. Preparedness actions... Review your severe weather safety procedures for the possibility of dangerous weather today. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A watch means that conditions are favorable for severe thunderstorms over the next several hours. If a severe thunderstorm warning is issued for your area, move to a place of safety, ideally in an interior room on the lowest floor of a sturdy building. && ..Grams.. 02/26/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Sun Feb 26 2023 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS DURING THE DAY FROM ILLINOIS INTO OHIO... ...SUMMARY... Thunderstorms may produce a few damaging gusts or brief tornadoes Monday from parts of Illinois into Ohio and far northern Kentucky. ...Synopsis and Discussion... A potent shortwave trough will move from MO Monday morning toward Lower MI by 00Z, as a surface low occludes from IA toward Lake MI. The occluded front will translate east from IL into IN and OH, with a warm front moving from northern KY into central OH. The most favorable instability will be associated with the midlevel cold pocket, with up to 500 J/kg MLCAPE possible over IL and IN through 18Z. After this time, CAPE values will generally remain below 250 J/kg near the warm front with mid 50s F dewpoints common. An expansive area of strong shear will exist over the entire region, with 850 mb winds around 60 kt aiding strong SRH values. An arcing line of storms is expected to be ongoing ahead of the vort max across central IL early Monday, and is forecast to move into IN by 18Z. This activity may produce damaging winds or brief tornadoes given sufficient low-level instability and strong shear. Storm mode may remain linear, as these storms will be tied to the midlevel cooling. Farther east, additional cells may develop where heating occurs and into the warm advection zone from KY into OH. Isolated supercells may occur here, on the southern fringe of the midlevel vort max and near the warm front where shear will be strong. Degree of destabilization will be the main mitigating factor regarding tornado threat. ..Jewell.. 02/26/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Sun Feb 26 2023 Valid 261700Z - 271200Z The previous forecast (see below) generally remains on track, and only minor adjustments were made to the ongoing Elevated highlights. Latest visible satellite imagery and mosaic radar data show lingering cloud coverage and light rain over the eastern half of the Elevated area -- which is stunting boundary-layer heating/mixing. However, water vapor loops depict downslope-related drying expanding eastward from eastern NM into west TX, which should aid in cloud clearing/thinning during the next few hours. As a result, boundary-layer heating/mixing amid a shallow cool/moist layer (per 12Z observed soundings) should yield around 25 percent RH over the eastern half of the Elevated area by late this afternoon. ..Weinman.. 02/26/2023 .PREV DISCUSSION... /ISSUED 1143 PM CST Sat Feb 25 2023/ ...Synopsis... A pronounced mid-level shortwave trough and associated surface low with a trailing dryline will rapidly traverse the southern Plains today, resulting in dry and windy conditions across the southern High Plains. Behind the dryline, 30 mph sustained westerly surface winds and 20 percent RH will be common. These conditions will be most likely across far eastern New Mexico and southeast Colorado into the Oklahoma/Texas Panhandles and western Texas. Since RH may locally dip into the 15 percent range, some areas may also experience potentially high-end Critical meteorological conditions (particularly across the Trans Pecos region in southwest Texas). Nonetheless, fuels across the southern High Plains remain modestly receptive (at best) to wildfire spread, with only Elevated highlights in place to address fire weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Sun Feb 26 2023 Valid 261630Z - 271200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS CENTERED ON WESTERN...CENTRAL...AND NORTHERN OKLAHOMA... ...SUMMARY... A derecho is forecast with widespread damaging winds and embedded swaths of significant severe gusts from 80-110 mph, centered on parts of Oklahoma this evening into tonight. Embedded tornadoes are anticipated as well, with the greatest potential for strong (EF2-EF3) tornadoes across southwest Oklahoma this evening. ...Southern Great Plains to the Mid-MS Valley... Just-in-time moisture return from the western Gulf is still anticipated ahead of a powerful shortwave trough ejecting from the Southwest to the Lower MO Valley. 60+ F surface dew points remain confined from the Piney Woods of east TX to the Concho Valley and Edwards Plateau of west TX as of 16Z. Guidance continues to differ with the northern extent of this richer moisture by evening in KS/OK beneath a stout elevated mixed layer. Widespread cloudiness is also evident over much of the southern Great Plains, although clearing should occur from west to east across the High Plains. The net result should be a narrow plume of surface-based instability along the dryline from southwest KS to west TX between 21-00Z. Scattered convection will break out after 21Z along the dryline and become supercellular towards 00Z given very favorably enlarged low to mid-level hodographs. Further moistening into the evening should result in the most favorable potential for supercell tornadoes in southwest OK between 00-03Z, in addition to very large hail. Convection will likely grow quickly upscale into a solid QLCS, accelerating east-northeast with embedded supercells and mesovortices. Extreme low-level shear profiles in conjunction with strengthening of 700-mb winds to around 90 kts behind the line should result in widespread severe wind gusts. Embedded swaths of 80-110 mph winds both straightline and rotating are likely, with stronger speeds into the EF2 range possible, until the QLCS outpaces the richer moisture in the OK/KS/MO border area overnight. Scattered damaging winds from strong to severe gusts may linger through the early morning across MO towards the Mid-MS Valley, despite little to no buoyancy, given the intense low-level wind fields. ..Grams/Wendt.. 02/26/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0142 PM CST Sat Feb 25 2023 Valid 261200Z - 271200Z ...Southern High Plains and West Texas... Over all the previous forecast remains valid with only minor adjustments for the latest guidance. Elevated to locally critical fire-weather conditions are possible Sunday across portions of the southern High Plains. Very strong surface wind fields are expected with a rapidly deepening area of low pressure across southeastern CO. Surface gusts greater than 50 mph appear likely through the afternoon and may continue for a few hours after sunset. However strong winds will only partially overlap with sub-critical RH. Additionally, area fuels remain mostly unfavorable for sustained fire-weather concerns. See the previous discussion for more information. ..Lyons.. 02/25/2023 .PREV DISCUSSION... /ISSUED 0102 AM CST Sat Feb 25 2023/ ...Synopsis... A pronounced mid-level trough will rapidly eject into the Plains states tomorrow/Sunday, with intense surface low development likely across the southern High Plains. During the afternoon, a dryline will rapidly surge eastward across the southern High Plains as the surface low tracks toward the MS Valley. A strong surface pressure gradient will promote widespread 30+ mph sustained westerly winds with RH dropping to at least 20 percent by afternoon peak heating. The latest guidance consensus depicts the aforementioned surface winds/RH to overlap along the New Mexico/Texas border into southeast Colorado. Elevated highlights have been introduced and at least locally Critical conditions appear likely as well. Although fuels are not critically dry in these areas, nearly a month has gone by without appreciable precipitation accumulations, with forecast rainfall largely absent. As such, fine grasses should be dry enough to support some wildfire-spread potential. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sat Feb 25 19:45:01 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Feb 25 19:45:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0128 PM CST Sat Feb 25 2023 Valid 252000Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms remain possible along the coast of southern California, and from northeast Oklahoma into the Ozarks. A few weak thunderstorms remain possible today in association with the cold upper low moving into southern CA, and from eastern OK into AR through tonight as weak instability couples with warm advection to support scattered elevated convection. ..Jewell.. 02/25/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sat Feb 25 2023/ ...Synopsis and Discussion... Deep upper low continues to progress southward off the southern CA coast. This progression is expected to trend more eastward with time, bringing the upper low across southern CA later tonight and into southern NV by early tomorrow morning. Robust wind fields will persist within the southern periphery of this system, with 100+ kt at 500-mb noted throughout the period. Strong forcing for ascent and cold mid-level temperatures will accompany this system, contributing to the potential for thunderstorms across southern CA both within the more banded convection ahead of the low and the more cellular convection at it moves overhead. Farther east, subtropical ridging centered over the FL Keys is expected to persist, with moderate mid-level flow between this ridge, the upper low farther west, and upper troughing farther north. A robust jet streak exists from the Mid MS Valley into the Northeast within this confluent westerly flow aloft. Broad ascent within the right entrance region of this jet will contribute to showers and isolated thunderstorms across the TN Valley and Mid-South this afternoon. Additional isolated thunderstorms are possible later tonight into tomorrow morning across eastern OK amid the strengthening warm-air advection and modest elevated buoyancy. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1140 AM CST Sat Feb 25 2023 Valid 261200Z - 271200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER WESTERN OKLAHOMA... ...SUMMARY... Significant damaging wind and a few tornadoes are expected from the eastern Texas Panhandle during the late afternoon across much of Oklahoma through the evening, with a wind threat persisting into Missouri overnight. Widespread wind damage is possible. ...Synopsis... A potent shortwave trough with midlevel speed max over 120 kt will move quickly across AZ and NM during day and into western TX, KS and OK during the late afternoon and evening. This wave will take on a negative tilt after 00Z as it continues across MO and into western IL by 12Z Monday. A tight midlevel temperature gradient will exist with this system, resulting in rapid height falls. At the surface, a low will develop from eastern CO into western KS during the afternoon, and will continue to deepen as it pivots into northern MO and southern IA through Monday morning. A cold front will extend south from the low and move rapidly east through the period, as southerly winds over the warm sector bring low-level moisture north. Extreme shear profiles coupled with returning moisture and strong lift will likely result in a corridor of particularly damaging winds. ...TX/OK/KS... Warm/moist advection will be underway on Sunday with a relatively cool/capped air mass in place early. As the system rapidly approaches, prolonged mixing with strong southerly winds should result in a corridor of SBCAPE of 500-1000 J/kg, from northwest TX into the TX Panhandle and western OK by 00Z. Heating over western areas will remove the cap, and late afternoon storms are expected over TX. These will likely be supercells capable of hail and a few tornadoes, with tornado strength dependent on degree of moisture return/potential for 60s F dewpoints. A strong tornado may occur prior to the expected upscale growth to a linear MCS along the cold front. As the line of storms develops into western OK, extreme shear should aid damaging wind potential, and a few tornadoes will remain possible within the line. Effective SRH value over 500 m2/s2 are likely, perhaps up to 750 m2/s2 during the evening as the low-level jet increases to over 70 kt. The most favorable corridor of damage is expected to be along and north of the tight midlevel temperature gradient, which will also travel along the northern portion of the warm sector/better moisture. Strong lift will easily remove the cap along the cold front, with winds behind this line becoming westerly. Further supporting significant wind damage potential will be the rare nocturnal boundary-layer mixing and 850 mb winds of 60 kt out of the west. ...MO/IL... A mature line of severe storms is expected to move coincident with the midlevel vort max as it moves out of OK and KS, and proceeds into the MO/Mid MS Valley overnight. Forecast soundings indicate weak instability, but extreme wind fields will exist. Further, an area of steep lapse rates will accompany this system, further increasing the probability of strong winds aloft mixing to the surface. As such, have expanded the Marginal and Slight Risk areas into MO and IL. ..Jewell.. 02/25/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Sat Feb 25 2023 Valid 251700Z - 261200Z ...NO CRITICAL AREAS... Overall the previous forecast remains on track. Localized dry and breezy conditions will be possible for a few hours across portions of northeastern NM and the TX Panhandle this afternoon. However, poorly receptive fuels and limited overlap of dry and windy conditions should keep fire-weather concerns low. See the previous discussion for additional information. ..Lyons.. 02/25/2023 .PREV DISCUSSION... /ISSUED 1221 AM CST Sat Feb 25 2023/ ...Synopsis... Upper ridging will amplify some across the southern Plains as a mid-level trough approaches from the west today, encouraging surface low development across the southern High Plains, with some westerly downslope component of flow. Modestly dry and breezy conditions may develop by afternoon peak heating across northeastern New Mexico into extreme southeast Colorado and the western Oklahoma and Texas Panhandle areas. However, surface winds and RH should not meet Elevated/Critical criteria on a widespread or longer-term basis, precluding fire weather highlights this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more