Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1233 PM CDT Thu May 25 2023 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF BOTH THE NORTHERN AND SOUTHERN HIGH PLAINS REGION... ...SUMMARY... Severe thunderstorms are possible across the High Plains on Friday. Highest severe thunderstorm coverage is expected over eastern New Mexico and southeast Montana. ...Eastern New Mexico and adjacent portions of western Texas... Scattered thunderstorms are expected to be ongoing at the start of the period across the Texas Panhandle/South Plains and vicinity, potentially as an MCS shifting southeastward across the region. Meanwhile, daytime heating of the amply moist (50s to lower 60s) boundary layer beneath steep mid-level lapse rates will yield moderate destabilization in areas away from any remnant cloud cover. As such, scattered, afternoon convective development is expected across eastern New Mexico and into adjacent portions of Texas, with more isolated development expected as far south as the Permian Basin and Big Bend area. With moderate westerly flow across the area, atop low-level southeasterlies, organized/rotating storms are expected. Along with potential for large hail and locally damaging winds, a tornado or two will also be possible. Tornado potential could be slightly augmented near/north of a possible outflow from the earlier storms/MCS, but will refrain from any possible bump up to 5% probability at this time, due to uncertainty with respect to prior convective evolution. Storms will likely increase in coverage/grow upscale during the evening, possibly into a loosely organized MCS that would shift eastward across the South Plains region. Severe risk should gradually diminish through the late evening/overnight hours as the boundary layer diurnally stabilizes. ...Southeastern Montana/northeastern Wyoming vicinity... As a subtle mid-level disturbance moves north-northeastward toward the northern High Plains, afternoon storm development is expected to occur in the vicinity of lee troughing, from central/eastern Montana southward into Colorado, as the airmass diurnally destabilizes. While somewhat weak shear will prevail across the northern High Plains area, likely limiting overall severe potential to some degree, slightly greater shear is expected across the southeastern Montana vicinity, where a weak surface low may develop in response to the approach of the aforementioned upper feature. Here, a few stronger/weakly rotating storms may evolve by late afternoon and last into the early evening hours, accompanied by risk for large hail and locally damaging winds. Storms/severe risk will gradually diminish through late evening, as convection shifts eastward. ..Goss.. 05/25/2023 Read more

MD 0857 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN MONTANA
Mesoscale Discussion 0857 NWS Storm Prediction Center Norman OK 0504 PM CDT Wed May 24 2023 Areas affected...Eastern Montana Concerning...Severe potential...Watch unlikely Valid 242204Z - 250000Z Probability of Watch Issuance...20 percent SUMMARY...A few strong to severe thunderstorms will occur this evening over parts of eastern Montana. Large hail and gusty winds are possible. A watch is unlikely. DISCUSSION...Latest surface analysis shows a cold front extending from eastern Phillips County MT southwestward to west of Billings. Visible satellite imagery shows a cu field that clearly shows the front position. Scattered thunderstorms have begun to form along and ahead of front, in a moderately moist and unstable air mass (dewpoints in the upper 50s and MLCAPE of 1000-1500 J/kg). Steep mid-level lapse rates will promote robust updrafts, but rather weak southerly flow through the low/mid troposphere will limit overall convective organization (effective shear < 25 knots). A few organized multicell storms capable of hail and gusty winds are expected for the next few hours, but current indications are that the majority of storms will remain below severe limits. Therefore not currently planning on watch issuance. ..Hart/Edwards.. 05/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...RIW... LAT...LON 48960520 46860525 44870616 44470710 45050812 45870897 46850782 47780759 49030774 48960520 Read more

MD 0855 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST CO
Mesoscale Discussion 0855 NWS Storm Prediction Center Norman OK 0346 PM CDT Wed May 24 2023 Areas affected...Southeast CO Concerning...Severe potential...Watch unlikely Valid 242046Z - 242245Z Probability of Watch Issuance...20 percent SUMMARY...Storms capable of isolated large hail and severe gusts will be possible into early evening. DISCUSSION...A supercell is ongoing at 2045 UTC near the Las Animas (Colorado) and Union (New Mexico) county line, with other intensifying storms noted farther west across Huerfano County, CO. Moderate buoyancy (MLCAPE of 1000-1500 J/kg) will continue to support the potential for vigorous updrafts through the remainder of the afternoon into early evening. The strongest deep-layer flow/shear is expected to remain farther south across eastern NM and west TX, but weekly veering wind profiles (as noted on the PUX VWP) are supporting effective shear of 25-35 kt, sufficient for some storm organization and at least transient supercell structures. While the strongest supercells are expected to remain south of the CO border, strong to potentially severe storms may continue to develop near the higher terrain, with some left-splitting supercells also potentially moving into southeast CO from northeast NM. Large hail is likely to be the most prominent hazard, though localized severe gusts will also be possible, especially if there are any outflow mergers and modest upscale growth. With the organized severe threat expected to remain relatively localized over southeast CO, watch issuance is considered unlikely, though this will be reevaluated depending on short-term observational trends through the remainder of the afternoon. ..Dean/Grams.. 05/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PUB... LAT...LON 37050380 37090479 37600498 38190491 38450455 38160308 37780275 37250264 37060286 37050380 Read more

WW 0235 Status Updates
STATUS FOR WATCH 0235 HAS NOT BEEN ISSUED YET Read more

WW 235 SEVERE TSTM NM OK TX 242025Z - 250300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 235 NWS Storm Prediction Center Norman OK 325 PM CDT Wed May 24 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Eastern New Mexico Western Oklahoma Panhandle Northwest Texas * Effective this Wednesday afternoon and evening from 325 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging winds and isolated significant gusts to 75 mph possible A tornado or two possible SUMMARY...Initial supercells are developing over the Raton Mesa and will likely form into a southeast-moving cluster this evening. More isolated supercells will be possible southward towards the Permian Basin. Very large hail and eventually severe wind gusts will be the main threat. A tornado or two will be most likely in the east-central New Mexico to southwest Texas Panhandle region in the early evening. The severe thunderstorm watch area is approximately along and 55 statute miles east and west of a line from 30 miles north northwest of Clayton NM to 40 miles southeast of Hobbs NM. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). 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 3 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 29025. ...Grams Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed May 24 2023 Valid 251200Z - 261200Z Elevated meteorological conditions may extend north and northwest of the current Elevated delineation tomorrow, but recent rainfall has left fuels less receptive across this region of the Southwest. Therefore, no changes were made to the outlook. See previous discussion below. ..Bentley.. 05/24/2023 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed May 24 2023/ ...Synopsis... Persistent troughing across the western US will continue to bring increased dry southwesterly flow across the Southwest on Thursday. The best overlap of drying fuels and windy/dry conditions will be across portions of southwestern New Mexico. An Elevated delineation was added where highest ensemble probabilities of Elevated conditions overlap with the driest fuels across southwestern New Mexico. Relative humidity reductions to around 10-15 percent amid sustained winds around 15-20 mph are expected within this region. Elevated meteorological conditions will be possible across much of Arizona and across southern Nevada. Recent rainfall has left fuels in this region unseasonably moist, precluding the need to include any additional areas. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Wed May 24 2023 Valid 242000Z - 251200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND INTO ADJACENT PORTIONS TEXAS PANHANDLE AND SOUTH PLAINS REGION... ...SUMMARY... Scattered severe thunderstorms are expected across the southern High Plains vicinity from 4 PM to Midnight CDT. A few intense supercells are anticipated and will be capable of very large hail. The threat for a few tornadoes should peak between 6 to 9 PM CDT and severe wind gusts between 8 to 11 PM CDT. ...Discussion... Expectations for evolution of the convective/severe risk -- as laid out in prior forecasts -- remain valid at this time, with strong/isolated severe storms occurring across portions of the Great Basin, and expected development of High Plains convection in the next 1 to 2 hours anticipated. The primary adjustment in this update has been to expand the MRGL risk area slightly in portions of Nevada/Utah, to more thoroughly corral the evolving hail/wind risk. ..Goss.. 05/24/2023 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed May 24 2023/ ...Eastern NM and west TX... In the wake of an MCS last night, a residual outflow boundary extends northwest from central TX and has become more diffuse near the South Plains and east-central NM border area. Richer boundary-layer moisture has been displaced southwest of the outflow, with upper 50s to mid 60s surface dew points common across the Permian Basin and Lower Pecos Valley. There will be gradual advection of this moisture to the north-northwest along the eastern NM/northwest TX border area. With very steep mid-level lapse rates of 9-9.5 C/km sampled by the 12Z MAF/ABQ soundings, relatively large buoyancy for the High Plains is anticipated at peak heating with MLCAPE from 1500-3000 J/kg. Scattered thunderstorms are most likely to develop in the late afternoon to early evening in/off the Raton Mesa vicinity, with more isolated activity expected south across eastern NM into the Trans-Pecos. While some weakness in the hodograph is expected around 700 mb, greater low-level curvature and speed shear above 700 mb relative to the past few days will yield a more elongated and relatively straight mid-upper hodograph. This should yield several discrete splitting supercells. Given the rather favorable CAPE/lapse rate environment, very large hail and potential for a few tornadoes appear increasingly probable. Storm-scale interference and eventual amalgamation of supercells, along with an evening increase in the low-level jet, should result in upscale growth and an increasing threat for severe wind gusts during the latter half of the evening. A southeast-moving MCS should emanate from the southwest TX Panhandle and northwest TX region, likely tracking near the outflow boundary from last night's MCS before weakening overnight. ...Northern Great Basin to eastern MT... While a broad upper trough persists over the West, multiple embedded vorticity maxima will rotate north-northeast across the northern Great Basin to northern High Plains areas. These will aid in scattered to widespread thunderstorm development later this afternoon. Buoyancy will remain weak (except over eastern MT) and deep-layer shear will be relatively modest, especially with eastern extent. Sporadic strong to locally severe wind gusts should be the primary hazard, with a secondary threat for isolated marginally severe hail. ...South/central FL... A diffuse front across central FL, and local sea breeze boundaries/collisions farther south, will again support scattered thunderstorms this afternoon. The stronger surface heating and larger MLCAPE will be confined to along and south of the front. Relatively cool mid-level temperatures near -11 C at 500 mb per 12Z MFL/TBW soundings should compensate for weak/weakening upper flow. Isolated strong-severe outflow gusts and small to marginally severe hail will be possible in the more robust clusters. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed May 24 2023 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF THE CENTRAL AND SOUTHERN HIGH PLAINS...AND ACROSS PORTIONS OF THE MONTANA VICINITY... ...SUMMARY... Isolated severe thunderstorms are possible across the central and southern High Plains, as well as parts of Montana and adjacent northern Wyoming, on Thursday. ...Central and southern High Plains... As a stagnant/stationary large-scale upper pattern persists, the focus for more active/locally severe storms will remain across the High Plains region Thursday. Presence of ample low-level moisture combined with diurnal heating will again result in afternoon destabilization, and subsequent scattered to isolated storm development. With low-level southeasterly flow beneath moderate mid-level westerlies, shear profiles supporting locally organized/rotating updrafts, and subsequent potential for upscale growth of storms into clusters propagating southeastward toward lower elevations, is apparent. As such, will maintain MRGL risk across the central and southern High Plains region for afternoon and evening convection. ...Central and southern Montana and vicinity... Daytime heating/destabilization is again expected across portions of the northern High Plains/northern Rockies area, as the primary upper trough remains in place just to the west. As multiple small mid-level disturbances continue rotating north-northeastward across the area, areas of scattered afternoon storm development are expected. With moderate mid-level south-southwesterlies aloft, some potential for upscale growth/organization appears to exist, within a zone centered over southern Montana. With potential for locally damaging winds and marginal hail with a couple of the stronger updrafts/clusters, inclusion of 5% wind/hail probabilities appears warranted at this time. ..Goss.. 05/24/2023 Read more

No Mesoscale Discussions are in effect as of Tue May 23 22:12:07 UTC 2023.

WW 0233 Status Updates
STATUS REPORT ON WW 233 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 W CVS TO 20 SSE TCC TO 45 SSW CAO TO 25 NE CAO. ..THORNTON..05/23/23 ATTN...WFO...ABQ...AMA...LUB...MAF... STATUS REPORT FOR WS 233 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NMC009-232340- NM . NEW MEXICO COUNTIES INCLUDED ARE CURRY TXC011-017-033-045-069-079-107-111-115-117-153-165-169-189-205- 219-227-279-303-305-317-335-359-369-375-381-415-437-445-501- 232340- TX . TEXAS COUNTIES INCLUDED ARE ARMSTRONG BAILEY BORDEN BRISCOE CASTRO COCHRAN CROSBY DALLAM DAWSON DEAF SMITH FLOYD GAINES GARZA HALE HARTLEY HOCKLEY HOWARD LAMB LUBBOCK LYNN MARTIN MITCHELL OLDHAM PARMER POTTER RANDALL SCURRY SWISHER TERRY YOAKUM Read more

WW 233 SEVERE TSTM NM TX 232025Z - 240200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 233 NWS Storm Prediction Center Norman OK 325 PM CDT Tue May 23 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northeast New Mexico Northwest Texas * Effective this Tuesday afternoon and evening from 325 PM until 900 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Isolated significant damaging wind gusts to 75 mph possible A tornado or two possible SUMMARY...A few supercells should develop southeast from northeast New Mexico and southward towards the South Plains. Primary threat will be large hail initially, with a greater wind threat as storms cluster eastward in the early evening. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 60 miles north northeast of Tucumcari NM to 95 miles south southeast of Lubbock TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). 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 2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30025. ...Grams Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0247 PM CDT Tue May 23 2023 Valid 232000Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEASTERN NEW MEXICO SOUTHEASTWARD INTO CENTRAL TEXAS... ...SUMMARY... Scattered severe thunderstorms will be possible across west to central Texas later this afternoon into tonight. A few intense storms are possible this evening. These will be capable of producing very large hail to around baseball size, severe wind gusts to around 80 mph, and brief tornadoes. ...Discussion... Aside from minor adjustments to the thunder line in a few areas, substantial changes to the outlook do not appear necessary at this time, as the current forecast continues to reflect ongoing and anticipated convective evolution. The most substantial change to the severe risk areas at this time, is to extend the 5% hail probability area northwestward across Florida into the Panhandle, where a few storms have occasionally intensified to levels consistent with hail in excess of 1" in diameter. ..Goss.. 05/23/2023 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue May 23 2023/ ...Southern High Plains to central TX... With widespread upper 50s to mid 60s surface dew points established and steeper mid-level lapse rates (around 1 C/km greater) sampled in 12Z MAF/AMA soundings compared to yesterday, larger MLCAPE from 2000-3000 J/kg is anticipated at peak heating ahead of the dryline in west to central TX. This will aid in a broader swath of severe thunderstorm potential during the late afternoon and evening relative to yesterday. A trio of minor MCVs are evident in water vapor/radar imagery...over east TX, north-central OK, and northeast NM. The latter impulse in conjunction with terrain enhancement and weak convergence along the dryline should aid in scattered thunderstorms forming towards mid-afternoon from northeast NM to the South Plains, with isolated thunderstorms also over the Trans-Pecos. Despite weak SRH initially, 30-35 kt effective bulk shear with relatively straight-line hodographs should foster outflow-dominated, splitting supercells with a primary threat of very large hail. Morning CAM guidance is varied in the duration of discrete supercell mode but the consensus appears to indicate a quicker transition to upscale growth relative to yesterday's event. The most likely area for MCS occurrence appears to be across the Big Country vicinity, with severe wind gust potential likely lingering longer tonight (wind reports yesterday ending around 02Z) and farther southeast into central TX, owing to the greater buoyancy today. ...FL... An MCV remains anchored over west-central AL with a low-amplitude trough extending south into the northern Gulf. Ahead of this, scattered thunderstorms are ongoing over the northeast Gulf and will also occur in a few hours along the sea breezes across the peninsula. Weak mid-level lapse rates sampled in 12Z soundings will continue to be a limiting factor to more substantial instability, but 20-30 kt effective bulk shear should support multicell clustering with a primary threat of sporadic downbursts producing locally damaging winds. ...Northeast NV/northwest UT and southeast ID... An upper trough with a series of embedded shortwave impulses will remain anchored from the Canadian Rockies south into northern CA. The fringe of enhanced mid-level south-southwesterlies should overlap a weak buoyancy plume characterized by MLCAPE from 250-750 J/kg over the northern Great Basin this afternoon. Scattered multicell clusters are expected in this corridor, with the potential for isolated severe gusts and small hail. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0245 PM CDT Tue May 23 2023 Valid 241200Z - 251200Z Latest ERC guidance suggests fuels may still be marginally dry, especially at lower terrain where less precipitation has fallen, into portions of west-central New Mexico. Therefore, since this is where winds and low relative humidity are expected to be strongest and driest, expanded the Elevated delineation across this region. However, the threat will primarily be at lower elevation in more fine fuels. ..Bentley.. 05/23/2023 .PREV DISCUSSION... /ISSUED 1217 AM CDT Tue May 23 2023/ ...Synopsis... Persistent troughing across the West Coast and the Pacific Northwest will lead to continued dry and windy conditions across much of the Southwest on Wednesday. Many areas within Arizona, southern Nevada, and northern and central New Mexico have received above normal rainfall in the last seven days. This will keep fire concerns low in these regions. Less rainfall was received across portions of far southern New Mexico, where fuels are expected to experience multiple days of windy and dry conditions earlier in the week. Given potential for modest drying of fuels, an Elevated delineation has been included within the region where relative humidity reductions to 10-15 percent amid sustained winds around 15-20 mph. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Tue May 23 2023 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS AREA... ...SUMMARY... Strong to locally severe thunderstorms are possible from the central and southern High Plains into northwest Texas. ...Central and southern High Plains into central Texas... While Day 1 convection will affect convective potential across portions of the southern Plains for Tuesday, it appears that destabilization of the seasonably moist boundary layer should result in scattered storm development during the afternoon and into the evening. While prior outflows will likely focus some convective development, a favored location for new storm development appears to be along the front range, south to northeastern New Mexico. While potential for locally gusty/damaging winds and hail will be possible across a broad area -- extending as far southeastward as central Texas, the greatest risk appears to exist across the TX/OK Panhandle vicinity. Here, storms are expected to develop over the higher terrain of northeastern New Mexico/southeastern Colorado, and then potentially grow upscale into a southeastward-propagating MCS through late afternoon and into the evening. Aided by low-level southeasterly flow beneath moderate mid-level northwesterlies, potential for damaging winds and hail can be expected as the MCS matures, spreading southeastward toward parts of western North Texas before weakening diurnally. ...Central and southern Florida... With the southern portion of an eastern U.S. trough lingering across Florida, providing both a slightly enhanced flow field aloft, and cool mid-level temperatures/steep lapse rates aloft, scattered, potentially strong afternoon thunderstorms are forecast to once again develop across much of the Florida Peninsula. Storms are expected near both sea-breeze boundaries, with some merging of storms over central portions of the Peninsula expected. Aided by the enhanced mid-level flow, a few of the stronger cells may produce locally strong/damaging wind gusts, and marginal hail into the early evening hours before storms diurnally diminish. ...Parts of the Great Basin into Montana... Modest afternoon destabilization is forecast across portions of the Great Basin/northern Rockies Tuesday, in the vicinity of a surface front associated with mid-level troughing that will remain quasi-stationary across the West. As afternoon convection develops near the front, and over terrain-favored areas, a few stronger/organized storms should evolve -- aided by mid-level south-southwesterlies around 30 kt. Given potential for locally strong/gusty winds with stronger cells through late afternoon/early evening, and potential for hail as well, upgrade to MRGL risk is warranted. ..Goss.. 05/23/2023 Read more

MD 0840 CONCERNING SEVERE THUNDERSTORM WATCH 231... FOR PORTIONS OF THE TX PANHANDLE...SOUTHWEST OK...AND WESTERN NORTH TEXAS
Mesoscale Discussion 0840 NWS Storm Prediction Center Norman OK 0345 PM CDT Mon May 22 2023 Areas affected...portions of the TX Panhandle...southwest OK...and western North Texas Concerning...Severe Thunderstorm Watch 231... Valid 222045Z - 222215Z The severe weather threat for Severe Thunderstorm Watch 231 continues. SUMMARY...Scattered thunderstorms are expected to continue this afternoon and into this evening. An initial threat for hail will likely transition more to damaging winds as cells cluster later this afternoon/evening. DISCUSSION...As of 2040 UTC, regional radar analysis showed scattered thunderstorms ongoing across portions of the TX Panhandle and far southwestern OK within WW231. Over the last couple of hours, storms have intensified with MRMS MESH showing cores supportive of hail in the 1-2" range. While storms have predominately been multi-cellular thus far, transient mid-level rotation has also been noted with area VADs showing effective shear of 25-30 kt. The mixed storm mode should continue this afternoon, with a threat for large hail and isolated damaging wind gusts. Given the number of storms, cells should gradually merge into one or more southeastward-moving clusters as outflow consolidates, similar to what the latest HRRR data suggests. A locally greater threat for damaging winds may then evolve across portions of the southeastern Panhandle where consolidating storms and stronger outflow may support some severe gusts this evening. ..Lyons.. 05/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...LUB...AMA... LAT...LON 33510197 34100202 34310193 34590171 34640166 35310111 35490105 35630091 35660060 35389981 35239949 34639934 33749952 33469992 33280024 33060124 33200182 33510197 Read more

MD 0839 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHWEST INTO CENTRAL MT
Mesoscale Discussion 0839 NWS Storm Prediction Center Norman OK 0341 PM CDT Mon May 22 2023 Areas affected...Parts of southwest into central MT Concerning...Severe potential...Watch unlikely Valid 222041Z - 222245Z Probability of Watch Issuance...20 percent SUMMARY...A threat for isolated hail and localized severe gusts will continue through the rest of the afternoon. Watch issuance remains unlikely. DISCUSSION...At 2030 UTC, a weakly organized storm cluster is moving across west-central MT, with some recent development noted into southwest MT. The cluster approaching Great Falls has mostly only produced subsevere hail and wind thus far, though some increase in severe potential remains possible as it moves into an increasingly unstable environment downstream, where steeper low-level lapse rates may favor an uptick in severe wind potential. However, with generally modest buoyancy and stronger deep-layer flow/shear expected to remain northwest of the strongest convection, the severe threat is still expected to remain isolated at best. Additional cells/clusters may evolve out of developing convection in southwest MT and move northeastward, with a similar risk of isolated hail and localized strong/severe gusts. The overall severe risk still appears too marginal and isolated for watch issuance. ..Dean/Grams.. 05/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX...MSO... LAT...LON 46660929 45921010 45081136 44511247 44871342 44981347 45391371 45601334 45981264 46401192 48371122 48540994 48570916 47660869 47210890 46660929 Read more

WW 0231 Status Updates
STATUS REPORT ON WW 231 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..05/22/23 ATTN...WFO...OUN...AMA...LUB... STATUS REPORT FOR WS 231 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OKC009-055-057-065-222140- OK . OKLAHOMA COUNTIES INCLUDED ARE BECKHAM GREER HARMON JACKSON TXC011-023-045-075-087-101-107-125-129-153-155-169-179-189-191- 197-263-269-275-303-305-345-433-437-483-487-222140- TX . TEXAS COUNTIES INCLUDED ARE ARMSTRONG BAYLOR BRISCOE CHILDRESS COLLINGSWORTH COTTLE CROSBY DICKENS DONLEY FLOYD FOARD GARZA GRAY HALE HALL HARDEMAN KENT KING KNOX LUBBOCK LYNN MOTLEY STONEWALL SWISHER WHEELER WILBARGER Read more

WW 231 SEVERE TSTM OK TX 221920Z - 230300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 231 NWS Storm Prediction Center Norman OK 220 PM CDT Mon May 22 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southwest Oklahoma Northwest Texas * Effective this Monday afternoon and evening from 220 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Scattered thunderstorms appear to be developing across the southeast Texas Panhandle and Low Rolling Plains. A few lower-end supercells and multicell clusters should develop with an initial threat of large hail transitioning to mainly severe wind during the early evening. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 60 miles north of Childress TX to 100 miles south southwest of Childress TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 30020. ...Grams Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Mon May 22 2023 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHWEST TEXAS VICINITY... ...SUMMARY... Isolated to scattered severe thunderstorms are likely across the Oklahoma/Texas Panhandles into northwest Texas through late evening. Large hail and severe wind gusts will be the primary hazards. ...Southern High Plains... The previous forecast largely remains on track with only minor adjustments needed. Wind probabilities were adjusted slightly to account for where convective initiation is occurring and confidence in the downstream wind threat is correspondingly higher. See MCD #838 for additional details on the near-term forecast. ...MT... Across MT, the initial convection noted in MCD #837 has demonstrated periods of organization with a bowing segment approaching the Great Falls, MT area. However, this segment has not maintained consistent intensity per GOES IR imagery over the past 1-2 hours, and downstream buoyancy remains uncertain. Confidence in a more widespread wind threat remains too limited for higher probabilities, but a few additional strong/severe storms remain probable. ..Moore.. 05/22/2023 .PREV DISCUSSION... /ISSUED 1129 AM CDT Mon May 22 2023/ ...TX/OK Panhandles to the Lower Pecos Valley... An MCV over southwest KS will drift quite slowly east-southeast through tonight. Modestly enhanced westerly mid-level flow (25-30 kts at 500 mb) will be displaced to the south of this MCV, centered across the southern TX Panhandle to the Permian Basin. Cloud coverage is most pronounced close to the MCV, with robust boundary-layer heating expected from the central/southern TX Panhandle southward towards the Pecos Valley. This heating will be coincident with the northwest extent of upper 50s to lower 60s surface dew points and the eastern extent of the elevated mixed layer, supporting moderate buoyancy with MLCAPE of 1500-2000 J/kg. Scattered thunderstorms should develop towards mid-afternoon across the eastern Panhandles into the South Plains, with more isolated activity into the Trans-Pecos. Within the belt of enhanced mid-level flow, adequate effective bulk shear (from 30-35 kts) and 0-3 km SRH should exist for a few slow-moving supercells. Flow will largely remain neutral to decreasing with height above the mid-levels north of the Permian Basin. A mix of transient supercells and multicell clusters can be expected, with a tendency for upscale growth along consolidating outflows by early evening as a modest increase in low-level warm theta-e advection occurs. Overall setup should favor isolated to scattered large hail from quarter to golf ball size and 50-70 mph wind gusts. Any MCS this evening in the western north TX vicinity should weaken after sunset as it impinges on increasing MLCIN to its southeast. ...MT... An upper-level trough will largely remain anchored over the Canadian to the northern U.S. Rockies during the period, with an embedded shortwave impulse rotating through north ID/northwest MT to the southern British Columbia/Alberta region this afternoon. An attendant surface cold front will push eastward across western MT and serve as a focus for isolated to scattered high-based thunderstorm development. Boundary-layer dew points from the mid to upper 40s suggest MLCAPE will remain weak from 500-1000 J/kg. Stronger mid to upper-level flow will be displaced west of the front, and as convection develops it will further outpace the better flow given the track of the embedded shortwave impulse. As such, isolated severe hail is possible mainly early. A few outflow-dominated multicell clusters should become the predominant mode with a primary threat of scattered strong to isolated severe wind gusts. ...FL and Northeast Gulf Coast... A minor mid-level impulse will drift slowly east over MS/AL, with a diffuse west/east-oriented quasi-stationary front to its southeast. Scattered thunderstorms are already ongoing along and just north of this front across south GA into extreme north FL. Additional thunderstorms will develop shortly along the sea breezes down the Peninsula, with numerous colliding convective outflows expected later this afternoon. Mid-level lapse rates will remain weak south, and more moderate to the north, with lower-level winds also remaining weak area wide. Pockets of scattered to broken cloud coverage in the Peninsula and separately over the FL Panhandle into south AL will support steeper low-level lapse rates that will favor sporadic strong to severe outflow gusts of 45-60 mph. Isolated, marginally severe hail will also be possible, mainly with any cells that can be rooted on southwest to south-moving outflows. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Mon May 22 2023 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHWEST TEXAS VICINITY... ...SUMMARY... Isolated to scattered severe thunderstorms are likely across the Oklahoma/Texas Panhandles into northwest Texas through late evening. Large hail and severe wind gusts will be the primary hazards. ...Southern High Plains... The previous forecast largely remains on track with only minor adjustments needed. Wind probabilities were adjusted slightly to account for where convective initiation is occurring and confidence in the downstream wind threat is correspondingly higher. See MCD #838 for additional details on the near-term forecast. ...MT... Across MT, the initial convection noted in MCD #837 has demonstrated periods of organization with a bowing segment approaching the Great Falls, MT area. However, this segment has not maintained consistent intensity per GOES IR imagery over the past 1-2 hours, and downstream buoyancy remains uncertain. Confidence in a more widespread wind threat remains too limited for higher probabilities, but a few additional strong/severe storms remain probable. ..Moore.. 05/22/2023 .PREV DISCUSSION... /ISSUED 1129 AM CDT Mon May 22 2023/ ...TX/OK Panhandles to the Lower Pecos Valley... An MCV over southwest KS will drift quite slowly east-southeast through tonight. Modestly enhanced westerly mid-level flow (25-30 kts at 500 mb) will be displaced to the south of this MCV, centered across the southern TX Panhandle to the Permian Basin. Cloud coverage is most pronounced close to the MCV, with robust boundary-layer heating expected from the central/southern TX Panhandle southward towards the Pecos Valley. This heating will be coincident with the northwest extent of upper 50s to lower 60s surface dew points and the eastern extent of the elevated mixed layer, supporting moderate buoyancy with MLCAPE of 1500-2000 J/kg. Scattered thunderstorms should develop towards mid-afternoon across the eastern Panhandles into the South Plains, with more isolated activity into the Trans-Pecos. Within the belt of enhanced mid-level flow, adequate effective bulk shear (from 30-35 kts) and 0-3 km SRH should exist for a few slow-moving supercells. Flow will largely remain neutral to decreasing with height above the mid-levels north of the Permian Basin. A mix of transient supercells and multicell clusters can be expected, with a tendency for upscale growth along consolidating outflows by early evening as a modest increase in low-level warm theta-e advection occurs. Overall setup should favor isolated to scattered large hail from quarter to golf ball size and 50-70 mph wind gusts. Any MCS this evening in the western north TX vicinity should weaken after sunset as it impinges on increasing MLCIN to its southeast. ...MT... An upper-level trough will largely remain anchored over the Canadian to the northern U.S. Rockies during the period, with an embedded shortwave impulse rotating through north ID/northwest MT to the southern British Columbia/Alberta region this afternoon. An attendant surface cold front will push eastward across western MT and serve as a focus for isolated to scattered high-based thunderstorm development. Boundary-layer dew points from the mid to upper 40s suggest MLCAPE will remain weak from 500-1000 J/kg. Stronger mid to upper-level flow will be displaced west of the front, and as convection develops it will further outpace the better flow given the track of the embedded shortwave impulse. As such, isolated severe hail is possible mainly early. A few outflow-dominated multicell clusters should become the predominant mode with a primary threat of scattered strong to isolated severe wind gusts. ...FL and Northeast Gulf Coast... A minor mid-level impulse will drift slowly east over MS/AL, with a diffuse west/east-oriented quasi-stationary front to its southeast. Scattered thunderstorms are already ongoing along and just north of this front across south GA into extreme north FL. Additional thunderstorms will develop shortly along the sea breezes down the Peninsula, with numerous colliding convective outflows expected later this afternoon. Mid-level lapse rates will remain weak south, and more moderate to the north, with lower-level winds also remaining weak area wide. Pockets of scattered to broken cloud coverage in the Peninsula and separately over the FL Panhandle into south AL will support steeper low-level lapse rates that will favor sporadic strong to severe outflow gusts of 45-60 mph. Isolated, marginally severe hail will also be possible, mainly with any cells that can be rooted on southwest to south-moving outflows. Read more