Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 PM CDT Sun May 07 2023 Valid 081200Z - 091200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 05/07/2023 .PREV DISCUSSION... /ISSUED 0145 AM CDT Sun May 07 2023/ ...Synopsis... In the mid levels, broad troughing over the central Rockies and western US will weaken and retrograde as weak ridging develops over the southern Rockies and Plains. Flow aloft will weaken substantially, limiting the magnitude of surface winds over much of NM and the southern High Plains. However, warm temperatures and a dry air mass will persist over the region Monday, with humidity values expected well below 15%. Locally elevated fire-weather conditions may develop for a few hours in the afternoon with locally gusty surface winds. Though confidence in the coverage of sustained elevated fire-weather concerns is too low to introduce an Elevated area. ...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 1230 PM CDT Sun May 07 2023 Valid 081200Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MISSOURI VALLEY ACROSS THE OHIO VALLEY... ...SUMMARY... Scattered severe storms are most probable from the mid Mississippi Valley into the Ohio Valley, with damaging winds and hail. Sporadic severe storms cannot be ruled out anywhere from Texas to the Appalachians. ...Synopsis... A low-predictability weather pattern will exist on Monday, with a belt of modest midlevel flow from the central Plains across the OH Valley, and a large area of instability from the southern Plains to the OH and TN Valleys. Of primary focus will be a midlevel wave positioned from IA into northern IL Monday morning. This feature is forecast to move east/southeast across the OH Valley states, providing enhanced wind speeds and deep layer shear. A weak surface low will also track from IL to WV with the associated midlevel wave, and this corridor will be the main focus for potential damaging winds and hail. A cold front will extend southwestward from the low, from southern MO into OK, with a very moist and unstable air mass to the south. In addition, a dryline will stretch from northwest TX southward toward the Big Bend. Elsewhere, a shortwave trough will affect parts of northern CA and NV into OR and ID, providing cool air aloft, weak instability and scattered afternoon thunderstorms. Locally gusty winds or small hail may occur. ...Lower MO/Mid MS/OH Valleys... The initiation of severe potential may be tied to the position of early day storms over the IA/IL/MO area Monday morning. These storms and associated outflow may persist throughout the morning with an increasing severe wind risk as the air mass becomes very unstable. Forecast soundings show steep midlevel lapse rates and sufficient midlevel flow to produce an MCS producing wind damage. However, if the early morning storms have not produced much outflow, then afternoon development may be cellular initially, producing large hail and perhaps a tornado given effective SRH over 200 m2/s2 ahead of the low. In summary, nearly all modes of severe will be possible from eastern MO into OH and KY, primarily with damaging wind and large hail. While predictability is low, the potential for a concentrated corridor of wind damage could develop, necessitating higher probabilities in later updates. ...AR into OK and parts of western TX... The boundary moving out of MO into AR, extending west into OK, will likely provide a focus for diurnal development, as heating of a moist air mass results in 3000-4000 J/kg MUCAPE. Westerly flow aloft at this latitude will be generally weak, but low-level convergence may be enough to initiate scattered clusters of storms along this front from afternoon through evening. Some of the stronger storms will likely produce large hail or locally damaging gusts. Farther south along the dryline into TX, strong heating will totally erode the capping inversion, and at least isolated thunderstorms are expected, producing localized strong gusts or hail. ..Jewell.. 05/07/2023 Read more

WW 0190 Status Updates
STATUS FOR WATCH 0190 HAS NOT BEEN ISSUED YET Read more

WW 190 TORNADO IA MO 062055Z - 070400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 190 NWS Storm Prediction Center Norman OK 355 PM CDT Sat May 6 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southern Iowa Northern Missouri * Effective this Saturday afternoon and evening from 355 PM until 1100 PM CDT. * Primary threats include... A couple tornadoes possible Scattered large hail likely with isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Thunderstorms will rapidly intensify over northwest Missouri and southwest Iowa this afternoon and track eastward across the watch area. Supercells capable of very large hail and a tornado or two are expected. The tornado watch area is approximately along and 60 statute miles north and south of a line from 60 miles north northwest of Saint Joseph MO to 30 miles south of Ottumwa IA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and 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. && OTHER WATCH INFORMATION...CONTINUE...WW 189... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Hart Read more

WW 0189 Status Updates
STATUS FOR WATCH 0189 HAS NOT BEEN ISSUED YET Read more

WW 189 SEVERE TSTM OK TX 062040Z - 070400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 189 NWS Storm Prediction Center Norman OK 340 PM CDT Sat May 6 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of South-central Oklahoma Central and Northern Texas * Effective this Saturday afternoon and evening from 340 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph likely Scattered large hail and isolated very large hail events to 3 inches in diameter likely SUMMARY...Scattered intense thunderstorms are expected from late afternoon into this evening. Very large hail to around 3 inches in diameter and damaging gusts to 75 mph will be possible with these storms as they track east/northeast. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 30 miles northwest of Ardmore OK to 45 miles south southeast of Abilene TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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 23030. ...Leitman Read more

MD 0690 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR MAINLY NORTHERN MISSOURI INTO SOUTHERN IOWA
Mesoscale Discussion 0690 NWS Storm Prediction Center Norman OK 0320 PM CDT Sat May 06 2023 Areas affected...mainly northern Missouri into southern Iowa Concerning...Severe potential...Watch likely Valid 062020Z - 062245Z Probability of Watch Issuance...80 percent SUMMARY...Conditions have become favorable for isolated supercells to develop, with a threat of tornadoes and very large hail through early evening. DISCUSSION...A modifying outflow boundary/warm front now stretches from extreme southeast NE across northwest MO. Substantial TCU is developing near a weak surface low near the NE/KS/MO border area, with additional CU fields in the modifying air mass over southern IA. Stable billow clouds are noted over of northern MO, but continued air mass modification will continue. Indeed, strong boundary-layer mixing exists from eastern KS into western MO where temperatures have warmed into the upper 80s to 90s F, with surface gusts out of the south around 25 kt. Convergence near the weak low in combination with warming surface temperatures are expected to result in isolated supercell development between 21-23Z. Hodographs will favor due-east storm motions, while strong instability and 0-1 SRH around 150 m2/s2 favoring both very large hail and a couple tornadoes. ..Jewell.. 05/06/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...DVN...DMX...EAX...OAX...TOP... LAT...LON 41259492 41409248 40999202 40509190 40049197 39469237 39369275 39639432 39719478 39789527 39799563 40129590 40199592 40509575 40899553 41259492 Read more

MD 0689 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF CENTRAL/NORTHERN TX INTO SOUTH-CENTRAL OK
Mesoscale Discussion 0689 NWS Storm Prediction Center Norman OK 0308 PM CDT Sat May 06 2023 Areas affected...portions of central/northern TX into south-central OK Concerning...Severe potential...Watch likely Valid 062008Z - 062215Z Probability of Watch Issuance...80 percent SUMMARY...Vigorous thunderstorm development is expected by 21-23z/4-6pm CDT. Very large hail and scattered damaging gusts will be the main hazards associated with these storms through this evening. A severe thunderstorm watch will likely be needed in the next couple of hours. DISCUSSION...An expanding cumulus field from near San Angelo TX northeast toward Wichita Falls TX is becoming increasingly agitated this afternoon. Strong heating along a dryline has resulted in temperatures from the upper 80s to low 90s. To the east of the dryline, surface dewpoints from the upper 60s to low 70s F beneath very steep midlevel lapse rates (greater than 8 C/km) are contributing to MLCAPE values around 2500-3000 J/kg. 19z objective analysis indicated capping is also rapidly eroding. Thunderstorms are expected to develop close to the dryline by 22z/5 pm CDT. Given strong instability and favorable lapse rates, intensification may occur fairly rapidly. Deep-layer flow is relatively modest, but vertically veering wind profiles with some increase in midlevel southwesterly flow by 23-00z will result in effective shear magnitudes around 25-30 kt. Very large hail (to around 3 inch diameter) will be possible, especially early in storm evolution. Steep low-level lapse rates also may promote strong downburst winds. Wind potential also may increase with time/eastward extent if some upscale development into forward-propagating clusters/bowing segments occurs, as some some short term hi-res guidance suggests. ..Leitman/Hart.. 05/06/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...OUN...SJT...LUB... LAT...LON 31349948 31379990 31510025 31630048 31880061 32240065 32600044 33849920 34599830 34799790 34859744 34779708 34619683 34389674 34089672 33929676 32839740 32559755 32009798 31469882 31349936 31349948 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0302 PM CDT Sat May 06 2023 Valid 071200Z - 081200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHEAST NEW MEXICO AND EXTREME NORTHWEST TEXAS PANHANDLE... The elevated area has been expanded eastward into western Oklahoma where warm temperature will contribute to minimum relative humidity values falling into the upper-teens. Elsewhere, no changes were made to the ongoing forecast. ..Marsh.. 05/06/2023 .PREV DISCUSSION... /ISSUED 0149 AM CDT Sat May 06 2023/ ...Synopsis... Within the broad mid-level trough over the central Rockies, a subtle shortwave is expected to exit the Great Basin and pass over portions of the High Plains Sunday. Accompanied by a small increase in flow aloft, the lee low should deepen, aiding in stronger surface winds. With dry and windy surface conditions expected behind a trailing dryline, critical fire-weather conditions are possible. ...Southern High Plains... As the subtle shortwave trough passes over the Southwest and southern High Plains Sunday, gusty southwest surface winds are expected to develop over portions of eastern NM. Confidence has increased that sustained winds will reach 20-25 mph with higher gusts Sunday afternoon and evening. The dry downslope flow, hot temperatures, and poor overnight humidity recoveries will support widespread RH values below 15%. Elevated fire-weather conditions appear likely from eastern NM, into portions of southern CO with the most likely corridor for sustained critical conditions in northeastern parts of NM. Farther east into the western OK/TX Panhandles, fuels are more questionable owing to recent precipitation. However, several days of drying since suggest some potential for near-critical fire-weather conditions given gusty surface winds and low humidity behind the dryline. ...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 0259 PM CDT Sat May 06 2023 Valid 062000Z - 071200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHERN TEXAS INTO EXTREME SOUTH-CENTRAL OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF IOWA...ILLINOIS...AND NORTHERN MISSOURI... ...SUMMARY... Intense severe thunderstorm development remains likely during the late afternoon and evening across a portion of the southern Great Plains. Very large hail and destructive wind events are possible across the Big Country and North-Central Texas into southern Oklahoma. Severe thunderstorms capable or producing a few tornadoes, very large hail, and damaging gusts remain a concern across parts of the Mid-Mississippi Valley States this evening into tonight. ...20Z Update... One of the primary changes made to the Day 1 Outlook was to remove the Category 1/Marginal Risk from LA. Multiple training MCSs have overturned the airmass in this region, reducing buoyancy and the associated severe threat. The only other change to the Day 1 Outlook was to adjust the severe probabilities over IA into northwestern MO to align with a baroclinic zone, where a focus for initial discrete supercells exists before storms potentially grow upscale into an MCS later this evening. Otherwise, the remainder of the Outlook remains on track, with severe hail and wind likely with outflow dominant storms across the southern Plains. An instance or two of large hail may still accompany a small convective cluster across central IL (see Mesoscale Discussion 0688 for more details). Likewise, a couple of severe wind gusts remain possible with storms overspreading a relatively dry boundary layer over parts of NE into SD. ..Squitieri.. 05/06/2023 .PREV DISCUSSION... /ISSUED 1105 AM CDT Sat May 06 2023/ ...TX/OK... A broad/flat upper trough is present today over the western states, with a ridge axis across the MS Valley. A diffuse surface dryline is analyzed over west TX, and will mix eastward through the afternoon and provide the focus for intense thunderstorm development later today. Full sunshine will lead to dry-adiabatic lapse rates throughout most of the low/mid troposphere today near the dryline. High-based storms are expected to develop by mid-afternoon from near Wichita Falls southward to west of San Angelo, where high CAPE values and sufficient flow will support supercells storms capable of very large hail and damaging winds. These storms will persist through much of the evening and spread eastward. Richer low-level moisture profiles and strengthening low-level winds during the evening will maintain the wind/hail risk while also increasing the potential for a tornado or two, although early outflow dominance may complicate storm modes. ...IA/MO/IL... a small cluster of strong-severe storms is ongoing this morning over northeast MO. The air mass ahead of this activity is relatively cloudy and only marginally unstable, leading to considerable uncertainty regarding the longevity of the severe risk. A few 12z CAM solutions do show convective maintenance through much of the afternoon, so will maintain the SLGT risk into central IL for this scenario. Farther north and west, southeasterly low-level winds will continue to transport an increasingly moist airmass into parts of northern MO and southern IA. Partial afternoon heating is expected to lead to moderate CAPE and the development of isolated thunderstorms. The storms that form will track eastward through the late afternoon and evening across southern IA/northern MO and eventually into western IL. Confidence is low regarding the location and timing of development, so have opted to make few changes to the ongoing SLGT risk. However, there is relatively high conditional potential for supercell storm structures capable of large hail and isolated tornadoes for those storms that can develop. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Sat May 06 2023 Valid 071200Z - 081200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEBRASKA...IOWA...NORTHERN MISSOURI...EXTREME WESTERN ILLINOIS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF NORTHWEST TEXAS INTO FAR SOUTHWESTERN OKLAHOMA... ...SUMMARY... Severe storms with very large hail, hurricane force gusts, and isolated tornadoes will be possible across parts of the Mid Missouri Valley on Sunday. Severe wind/hail producing storms will also be possible in parts of the central and southern Plains, perhaps extending into parts of the southern Great Lakes and Ohio Valley into the Tennessee Valley and central Appalachians. ...Synopsis... A relatively complex convective scenario is in store for tomorrow/Sunday. An upper ridge will become established over the Mid-MS Valley and OH Valley regions while a mid-level trough will meander over the Interior West. Multiple mid-level impulses are expected to crest the ridge through tomorrow, potentially supporting multiple rounds of storms (including possible MCSs), some of which may be capable of supporting severe hazards. Meanwhile, a surface low and trailing dryline will become established across the Central and Southern Plains. Despite relatively weak shear in the presence of capping, some storms may develop across the southern Plains, supporting a severe threat. ...Central Plains into the Midwest... Multiple intense thunderstorms are expected to develop along a warm frontal zone across eastern NE into IA by late afternoon. Upper 60s to low 70s F dewpoints beneath 8+ C/km mid-level lapse rates will support over 4000 J/kg SBCAPE in spots amid elongated, slightly curved low to mid-level hodographs. Initial development should be supercellular with very large hail possible and perhaps a couple of tornadoes possible. However, overall modest shear profiles support supercell mergers into an intense MCS somewhere from far eastern NE into the southern half of IA by evening. Should this occur, a bow-echo MCS may manifest and produce several instances of severe gusts, a few of which may exceed 65 kts. ...Southern Plains... Isolated to potentially scattered thunderstorms should rapidly develop ahead of the dryline by afternoon peak heating. Upper 60s/lower 70s F surface dewpoints beneath 8-9 C/km mid-level lapse rates will support up to 4000 J/kg MLCAPE wherever low-level moisture does not mix out. Some guidance suggests that the development of a well-mixed boundary layer may result in only 2500 J/kg MLCAPE. Nonetheless, very high amounts of buoyancy amid steep tropospheric lapse rates should support intense thunderstorm development. With somewhat elongated hodographs, initial updrafts may be transient supercellular, with the risk of large hail. However, weak low-level shear should support outflow dominant storms with a severe wind threat. ...Mid MS Valley, TN/OH Valleys, Central Appalachians... Multiple MCSs may occur through the day, with an MCS expected to be traversing the mid-MS Valley into the OH/TN Valley areas at the start of the period (Sunday morning). This MCS should be in the weakening stages due to the stabilizing of the boundary layer. However, the MCS will move southeast along the eastern periphery of the upper ridge and 7+ C/km mid-level lapse rate plume, where at least some deep-layer and low-level shear will be present. As such, a few damaging gusts may still occur, including over portions of the central Appalachians, where increased diurnal heating may support a brief re-invigoration of convection along the leading line. It is possible that the intense MCS moving across the Midwest during the evening may approach the Mid MS, OH and TN Valleys overnight. Should this MCS endure, isolated damaging gusts will again be a concern. ...Portions of the northern High Plains... Scattered thunderstorms may develop along the higher terrain of the Black Hills by afternoon peak heating in the presence of surface lee troughing. A warm, but dry boundary layer is expected to materialize by late afternoon in advance of the storms, with up to 9 C/km low-level lapse rates expected. Modest strengthening of the vertical wind profile will contribute to elongated hodographs, fostering the potential for storm organization. As such, short line segments may produce isolated severe gusts during the late afternoon hours. ..Squitieri.. 05/06/2023 Read more

WW 0188 Status Updates
STATUS FOR WATCH 0188 HAS NOT BEEN ISSUED YET Read more

WW 188 SEVERE TSTM CO KS NE 052150Z - 060500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 188 NWS Storm Prediction Center Norman OK 450 PM CDT Fri May 5 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northeast Colorado Northwest Kansas Central and Western Nebraska * Effective this Friday afternoon from 450 PM until Midnight CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Thunderstorms are expected to increase in coverage through the afternoon and evening across the watch area. Damaging wind gusts and hail will be possible with the stronger cells. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 50 miles west northwest of Imperial NE to 30 miles east of Hastings NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 187... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Hart Read more

WW 0187 Status Updates
STATUS FOR WATCH 0187 HAS NOT BEEN ISSUED YET Read more

MD 0682 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR FAR NORTHEAST CO...NE PANHANDLE AND SOUTHWEST NE...NORTHWEST KS
Mesoscale Discussion 0682 NWS Storm Prediction Center Norman OK 0354 PM CDT Fri May 05 2023 Areas affected...far northeast CO...NE Panhandle and southwest NE...northwest KS Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 052054Z - 052300Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms are forecast to develop over northeast CO/NE Panhandle and spread east while intensifying. A severe thunderstorm watch will likely need to be considered in the next 1-2 hours. DISCUSSION...Visible satellite imagery shows developing thunderstorms near the NE/WY border and other deepening convection is noted over northeast CO near I-76. The northern rim of richer low-level moisture has reached I-70 in central KS with 60 deg F dewpoints at several observation sites. A drier but more deeply mixed boundary layer is located over northwest KS into southwest NE and the NE Panhandle. Surface temperatures have warmed into the lower 80s near the NE/CO/KS border with mid 70s far north over the NE Sandhills. Objective analysis indicates MLCAPE ranges from 500-1500 J/kg across the central High Plains. An increase in buoyancy is progged over northwest KS (1500-2000 J/kg MLCAPE) on the northern rim of richer moisture as it advects into the area during the evening. Forecast guidance suggests effective shear generally in the 30-45 kt range which will support storm organization. Very steep low to mid-level lapse rates will favor at least isolated to widely scattered instances of large to very large hail (max hail diameters 2.0 to 2.75 inches) with mature supercells. Isolated to widely scattered severe gusts of 60-75 mph are possible, especially as cold pools consolidate during the evening and some upscale growth occurs coincident with a strengthening of the LLJ. ..Smith/Guyer.. 05/05/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GID...LBF...GLD...BOU...CYS... LAT...LON 41820372 42460339 42770257 42430148 41019954 40149935 39269981 38910111 39260218 41070347 41820372 Read more

WW 187 SEVERE TSTM OK TX 052055Z - 060300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 187 NWS Storm Prediction Center Norman OK 355 PM CDT Fri May 5 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Far Southern Oklahoma Central and North Texas * Effective this Friday afternoon and evening from 355 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Widely scattered thunderstorms will continue to develop and intensify, initially across central/western North Texas through late afternoon and early evening. This includes the potential for supercells capable of large hail. Storms could eventually cluster by early evening as they persist eastward toward the I-35 corridor. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 60 miles west northwest of Sherman TX to 40 miles west southwest of Austin TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). 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 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 25020. ...Guyer Read more

MD 0681 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR CENTRAL TEXAS
Mesoscale Discussion 0681 NWS Storm Prediction Center Norman OK 0242 PM CDT Fri May 05 2023 Areas affected...central Texas Concerning...Severe potential...Watch likely Valid 051942Z - 052145Z Probability of Watch Issuance...80 percent SUMMARY...Scattered storms are expected to form over the next few hours across central Texas, with a threat of severe hail and a few severe gusts. DISCUSSION...A CU field continues to expand over parts of the Edwards Plateau, with additional towering CU extending east/northeast toward Denton. Strong heating over the elevated terrain has led to an uncapped air mass, with modest destabilization currently as dewpoints have mixed. Coincidentally, all of this convection happens to be colocated with the 850 mb theta-e ridge. With time, and despite only weak convergence, a few storms will likely emerge out of the coalescing CU field, with a threat of locally damaging hail or severe gusts. Mid to high level winds are not particularly strong, suggesting multicell storm mode with sporadic strong cores and updrafts propagating in various directions, with downdrafts aided by the well-mixed boundary layer. ..Jewell/Guyer.. 05/05/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...EWX...SJT... LAT...LON 31230013 31860022 32749991 32979957 33179740 32979720 32569686 31949687 31299703 30699725 30389760 30489900 30739971 31230013 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0223 PM CDT Fri May 05 2023 Valid 052000Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL/NORTH TEXAS AND THE CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms are most likely across central Texas and in the central Great Plains, centered on 4 to 10 PM CDT. Large hail and locally damaging winds are possible. ...20z Update... Only minor changes have been made to the ongoing outlook. The Marginal risk (level 1 of 5) over Louisiana has been trimmed based on location of ongoing convection and trends in short-term forecast guidance. Otherwise, the only other changes have been to trim the 10 percent general thunderstorm line across parts of OK/southeast KS/southwest MO/far northwest AR. Strong capping should preclude thunderstorm development in these areas through the remainder of the period. ..Leitman.. 05/05/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri May 05 2023/ ...Central/North Texas... A moist/moderately unstable environment is expected near/east of the north/south-oriented dryline this afternoon. Ample insolation/mixing near the dry line should contribute to isolated thunderstorm development by late afternoon particularly across central Texas near/west of I-35. Despite weak low-level flow, 30-40 kt effective bulk shear will support a few slow-moving supercells with mid-level rotation capable of producing very large hail. Although convective inhibition will nocturnally increase, there is some potential that a cluster of storms could persist for a time this evening across central Texas, with damaging winds a possibility. ...Central High Plains... On the east/south periphery of the Great Basin-centered upper trough, a shortwave trough/speed max over the southern Rockies this morning should reach and increasingly influence the central High Plains by late afternoon and evening. Deepening of a lee trough will occur through peak heating, with modest low-level moisture advecting west-northwestward across the region. Initial high-based thunderstorm development is expected across far eastern Wyoming/Nebraska Panhandle and northeast Colorado, with storms expected to intensify as the move into somewhat richer low-level moisture and greater buoyancy, including supercells amidst 40+ kt effective shear. Large hail should be the most common hazard, but a locally damaging wind gust and/or low tornado potential will exist as well. The severe threat could persist eastward into central Nebraska/north-central Kansas early in the overnight. ...Lower Mississippi Valley... The remnants of an overnight/early morning convective cluster continue to spread offshore into the northern Gulf of Mexico generally to the south of Mobile. Dual weak mid-level perturbations/MCV will continue to spread eastward away from a northwest/southeast-oriented convectively reinforced warm front and zone of differential heating. Nevertheless, storm redevelopment, such as what may already being occurring across the ArkLaMiss vicinity, is expected at least on a widely scattered sense as outflow modifies and the boundary warms/destabilizes. Isolated instances of severe hail and/ow wind will be possible this afternoon through early evening as storms spread southeastward. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0223 PM CDT Fri May 05 2023 Valid 052000Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL/NORTH TEXAS AND THE CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms are most likely across central Texas and in the central Great Plains, centered on 4 to 10 PM CDT. Large hail and locally damaging winds are possible. ...20z Update... Only minor changes have been made to the ongoing outlook. The Marginal risk (level 1 of 5) over Louisiana has been trimmed based on location of ongoing convection and trends in short-term forecast guidance. Otherwise, the only other changes have been to trim the 10 percent general thunderstorm line across parts of OK/southeast KS/southwest MO/far northwest AR. Strong capping should preclude thunderstorm development in these areas through the remainder of the period. ..Leitman.. 05/05/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri May 05 2023/ ...Central/North Texas... A moist/moderately unstable environment is expected near/east of the north/south-oriented dryline this afternoon. Ample insolation/mixing near the dry line should contribute to isolated thunderstorm development by late afternoon particularly across central Texas near/west of I-35. Despite weak low-level flow, 30-40 kt effective bulk shear will support a few slow-moving supercells with mid-level rotation capable of producing very large hail. Although convective inhibition will nocturnally increase, there is some potential that a cluster of storms could persist for a time this evening across central Texas, with damaging winds a possibility. ...Central High Plains... On the east/south periphery of the Great Basin-centered upper trough, a shortwave trough/speed max over the southern Rockies this morning should reach and increasingly influence the central High Plains by late afternoon and evening. Deepening of a lee trough will occur through peak heating, with modest low-level moisture advecting west-northwestward across the region. Initial high-based thunderstorm development is expected across far eastern Wyoming/Nebraska Panhandle and northeast Colorado, with storms expected to intensify as the move into somewhat richer low-level moisture and greater buoyancy, including supercells amidst 40+ kt effective shear. Large hail should be the most common hazard, but a locally damaging wind gust and/or low tornado potential will exist as well. The severe threat could persist eastward into central Nebraska/north-central Kansas early in the overnight. ...Lower Mississippi Valley... The remnants of an overnight/early morning convective cluster continue to spread offshore into the northern Gulf of Mexico generally to the south of Mobile. Dual weak mid-level perturbations/MCV will continue to spread eastward away from a northwest/southeast-oriented convectively reinforced warm front and zone of differential heating. Nevertheless, storm redevelopment, such as what may already being occurring across the ArkLaMiss vicinity, is expected at least on a widely scattered sense as outflow modifies and the boundary warms/destabilizes. Isolated instances of severe hail and/ow wind will be possible this afternoon through early evening as storms spread southeastward. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0223 PM CDT Fri May 05 2023 Valid 052000Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL/NORTH TEXAS AND THE CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms are most likely across central Texas and in the central Great Plains, centered on 4 to 10 PM CDT. Large hail and locally damaging winds are possible. ...20z Update... Only minor changes have been made to the ongoing outlook. The Marginal risk (level 1 of 5) over Louisiana has been trimmed based on location of ongoing convection and trends in short-term forecast guidance. Otherwise, the only other changes have been to trim the 10 percent general thunderstorm line across parts of OK/southeast KS/southwest MO/far northwest AR. Strong capping should preclude thunderstorm development in these areas through the remainder of the period. ..Leitman.. 05/05/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri May 05 2023/ ...Central/North Texas... A moist/moderately unstable environment is expected near/east of the north/south-oriented dryline this afternoon. Ample insolation/mixing near the dry line should contribute to isolated thunderstorm development by late afternoon particularly across central Texas near/west of I-35. Despite weak low-level flow, 30-40 kt effective bulk shear will support a few slow-moving supercells with mid-level rotation capable of producing very large hail. Although convective inhibition will nocturnally increase, there is some potential that a cluster of storms could persist for a time this evening across central Texas, with damaging winds a possibility. ...Central High Plains... On the east/south periphery of the Great Basin-centered upper trough, a shortwave trough/speed max over the southern Rockies this morning should reach and increasingly influence the central High Plains by late afternoon and evening. Deepening of a lee trough will occur through peak heating, with modest low-level moisture advecting west-northwestward across the region. Initial high-based thunderstorm development is expected across far eastern Wyoming/Nebraska Panhandle and northeast Colorado, with storms expected to intensify as the move into somewhat richer low-level moisture and greater buoyancy, including supercells amidst 40+ kt effective shear. Large hail should be the most common hazard, but a locally damaging wind gust and/or low tornado potential will exist as well. The severe threat could persist eastward into central Nebraska/north-central Kansas early in the overnight. ...Lower Mississippi Valley... The remnants of an overnight/early morning convective cluster continue to spread offshore into the northern Gulf of Mexico generally to the south of Mobile. Dual weak mid-level perturbations/MCV will continue to spread eastward away from a northwest/southeast-oriented convectively reinforced warm front and zone of differential heating. Nevertheless, storm redevelopment, such as what may already being occurring across the ArkLaMiss vicinity, is expected at least on a widely scattered sense as outflow modifies and the boundary warms/destabilizes. Isolated instances of severe hail and/ow wind will be possible this afternoon through early evening as storms spread southeastward. Read more