SPC Center Public Severe Weather Outlook (PWO)
2024-04-27
SPC Mesoscale Discussions
Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0649 AM CDT SAT APR 27 2024 ...Severe thunderstorms expected over parts of the southern and central Great Plains today through tonight... * LOCATIONS... Oklahoma North Texas Kansas Western Missouri * HAZARDS... Several tornadoes, a few intense Widespread large hail, some baseball size Scattered damaging winds, some hurricane force * SUMMARY... Numerous severe thunderstorms are likely today and tonight across the southern and central Plains into the lower to mid Missouri Valley. The greatest potential for severe storms will be from north Texas into Oklahoma and southeast Kansas, where strong tornadoes, very large hail over 2 inches in diameter and widespread damaging winds (some over 70 mph), are expected to occur. A broader area of severe threat will extend from south-central Texas north-northeastward to the Great Lakes. 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 tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building.
https://www.spc.noaa.gov/products/outlook/pwo.htmlSPC Mesoscale Discussions
SPC MD 537
2024-04-27
SPC Mesoscale Discussions
MD 0537 CONCERNING SEVERE POTENTIAL…WATCH LIKELY FOR PARTS OF NORTHWEST TX INTO WESTERN OK
Mesoscale Discussion 0537 NWS Storm Prediction Center Norman OK 0529 AM CDT Sat Apr 27 2024 Areas affected...Parts of northwest TX into western OK Concerning...Severe potential...Watch likely Valid 271029Z - 271200Z Probability of Watch Issuance...80 percent SUMMARY...Severe storm development is possible toward sunrise. Large hail will be possible initially, but the tornado threat will increase through the morning. Watch issuance is likely prior to 7 AM CDT. DISCUSSION...Rich low-level moisture is streaming into parts of the TX South Plains and northwest TX this morning, in response to a strong southerly low-level jet noted on regional VWPs. Meanwhile, a strong mid/upper-level shortwave trough and attendant mid/upper-level jet are approaching the southern Rockies. A cirrus plume now moving over far west TX may be indicative of increasing ascent in advance of the shortwave. As this ascent begins to impinge on returning moisture across northwest TX, thunderstorm development is expected near or just before sunrise, with increasing storm coverage expected with time into parts of western OK. Initial storm development will likely be somewhat elevated, but MUCAPE of greater than 2000 J/kg and strong effective shear will support supercell potential with an initial threat of large hail (potentially in the 1.5 - 2 inch diameter range). As storms spread into western OK, a transition to surface-based convection will be possible later this morning, as MLCINH quickly erodes with even modest diurnal heating. A transition to one or more clusters is possible as storm coverage increases with time this morning, but increasingly favorable low-level moisture and wind profiles will support embedded supercells with an increasing tornado threat. Watch issuance is likely prior to 7 AM CDT. ..Dean/Thompson.. 04/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...LUB...AMA... LAT...LON 34029986 33970016 33960083 34230093 35110009 36019945 36869914 36939846 36549794 36019782 35349799 34419848 34029986
https://www.spc.noaa.gov/products/md/md0537.htmlSPC Mesoscale Discussions
SPC Day 1 Fire Weather Outlook
2024-04-27
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Sat Apr 27 2024 Valid 271200Z - 281200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN HIGH PLAINS... ...Synopsis... A strong mid-level jet streak will round the base of the western trough today, with strong lee cyclogenesis resulting across the High Plains. Strengthening flow amid very dry conditions will lead to Elevated to Critical fire weather concerns across portions of the southern High Plains into the central High Plains. ...Southern and Central High Plains... A deeply mixed air mass is expected to be in be in place by this afternoon across portions of eastern New Mexico into and eastward into the Oklahoma/Texas Panhandles into southwestern Kansas. In these regions, sustained surface winds 20-30 mph will overlap afternoon relative humidity reductions to around 5-10 percent. The Critical area was expanded further into southwestern Kansas, given recent trends. While some spotty Extremely Critical conditions are possible, fuels do not yet support inclusion of an Extremely Critical area at this time. ..Thornton.. 04/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product...
SPC Apr 27, 2024 0600 UTC Day 1 Convective Outlook
2024-04-27
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0253 AM CDT Sat Apr 27 2024 Valid 271200Z - 281200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTH TEXAS...OKLAHOMA...SOUTHEAST KANSAS AND FAR SOUTHWEST MISSOURI... CORRECTED FOR GEOGRAPHIC REFERENCE IN MISSOURI ...SUMMARY... Numerous severe thunderstorms are likely today and tonight across the southern and central Plains into the lower to mid Missouri Valley. The greatest potential for severe storms will be from north Texas into Oklahoma and southeast Kansas, where strong tornadoes, very large hail over 2 inches in diameter and widespread damaging winds (some over 70 mph), are expected to occur. A broader area of severe threat will extend from south-central Texas north-northeastward to the Great Lakes. ...Tornado Outbreak Expected Today From North Texas into Oklahoma...Southeast Kansas and Far Southwest Missouri... ...Southern Plains... An upper-level trough will move through the Desert Southwest today as an 80 to 90 knot mid-level jet translates quickly eastward through the base of the system. Ahead of the trough, a moist and unstable airmass will be in place across much of the southern and central Plains. At the surface, a low will move eastward across southwest Kansas with a dryline extending southward through far western Oklahoma and west Texas. Surface dewpoints to the east of the dryline will be in the mid to upper 60s F. In response to warm advection this morning, a cluster of thunderstorms is expected to develop to the east of the dryline across northwest Texas. This cluster is forecast to spread north-northeastward into western Oklahoma by late morning. Large hail and wind damage will be likely with the stronger cells within this cluster. An outflow boundary with this convection should setup across west-central Oklahoma by early afternoon, with a moist and unstable airmass extending eastward from the boundary across much of central and eastern Oklahoma northward into southeast Kansas. This undisturbed airmass is expected to be favored for the greatest severe threat this afternoon and evening. The mid-level jet is forecast to eject quickly northeastward across the southern Plains this afternoon. This will result in strong deep-layer shear across most of the southern Plains, and will create a large-scale mass response that will be very favorable for severe storms, including supercells and bowing line segments. As the core of the mid-level jet moves into the southern Plains during the mid to late afternoon, a 50 to 60 knot low-level jet will rapidly strengthen. RAP forecast sounding along and near the low-level jet during the late afternoon look very favorable for tornadoes, with backed surface flow, and long looping hodographs. As the low-level jet strengthens, 0-3 km storm-relative helicity is forecast to increase to around 400 m2/s2 across much of central and eastern Oklahoma into southwest Missouri. The more dominant and supercells that interact with the western and northern edge of the low-level jet are expected to become tornadic. Several strong tornadoes will be likely, and a few long-track EF3+ tornadoes will be possible. In addition to the tornado threat, forecast soundings have 700-500 mb lapse rates near 8 C/km across much of the warm sector this afternoon from north Texas to southeast Kansas. This will be favorable for very large hail, with hailstones over 2 inches in diameter likely with the more intense storms. Later in the evening, a line of severe storms is expected to form, moving eastward across eastern Oklahoma and north Texas. Wind gusts over 70 mph will be possible with the more intense parts of the line. QLCS tornadoes will also be possible with rotating cells embedded in the line late this evening into the overnight period. ...Central Plains/Lower to Mid Missouri Valley... An upper-level low will move through the southern Rockies today, as the exit region of a mid-level jet overspreads the central Plains. At the surface, a warm front will be located from near a surface low in southwest Kansas east-northeastward into the mid Missouri Valley. This front will be a focus for convective development this afternoon. A band of severe storms is expected to form near the front and move northward across northern Kansas into southern Nebraska during the early to mid afternoon. RAP forecast soundings in northeast Kansas near the front from 18Z to 21Z have MLCAPE near 3000 J/kg, 0-6 km shear around 60 knots, and steep low to mid-level lapse rates. This environment will be very favorable for supercells with large hail. Hailstones greater than 2 inches in diameter will be possible with the more intense storms. In addition, forecast soundings have 0-3 km storm-relative helicity in the 250 to 300 m2/s2 range, suggesting that tornadoes will be likely with the more discrete supercells. A few strong tornadoes will be possible. Further west into northwest Kansas and eastern Colorado, cold temperatures aloft, strong large-scale ascent associated with an upper-level low, and strong deep-layer shear will likely support lower-topped supercells with large hail and strong wind gusts this afternoon. ...Mid to Upper Mississippi Valley/Great Lakes... An upper-level trough will move northeastward across the Great Lakes region today. From near the trough, and southwestward into the mid to upper Mississippi Valley, a wide corridor of moderate instability will be in place by afternoon. A warm front will be in located along the northern edge of the instability, from Iowa northeastward into south-central Wisconsin and north-central lower Michigan. As surface heating takes place and low-level convergence increases along the front, thunderstorms will likely form in the vicinity of the boundary. Forecast soundings near the front at 21Z have MLCAPE around 3000 J/kg, along with 40 knots of deep-layer shear. This should support supercells with potential for large hail and wind damage. The severe threat should be greatest during the late afternoon and early evening. ..Broyles/Thornton.. 04/27/2024
SPC Apr 27, 2024 0600 UTC Day 2 Convective Outlook
2024-04-27
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Sat Apr 27 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST TX NORTHWARD INTO THE UPPER MS VALLEY... ...SUMMARY... Strong to potentially severe thunderstorms will be possible Sunday from northeast Texas into parts of the upper Mississippi Valley. Damaging winds, hail, and a few tornadoes will all be possible. ...East TX into the upper MS Valley... A broad region of at least some severe potential is still expected on Sunday from northeast TX into parts of the upper MS Valley. Within this larger region, it appears the greatest relative threat may develop from northeast TX/southeast OK into western AR/northwest LA. However, with very extensive convection expected upstream on D1/Saturday, uncertainty is too high to increase probabilities at this time. A negatively tilted shortwave trough and attendant surface low are forecast to move from the central Plains toward the upper MS Valley on Sunday. Widespread convection will likely be ongoing at the start of the period from Texas toward the lower MO Valley, and potentially farther north into parts of the upper Midwest. Some lingering severe threat could accompany this morning convection, especially toward the ArkLaTex region where somewhat more favorable moisture/instability will be in place. There is some potential for morning convection to remain somewhat organized and continue eastward with a severe threat, but the greater concern will be with redevelopment in the wake of morning convection, with rich low-level moisture expected to remain in place along/ahead of the dryline, which will likely extend from eastern NE/KS into central OK/TX by late afternoon. One area of potential redevelopment will be immediately ahead of the ejecting shortwave trough from eastern KS/NE into western MO and southern IA, where a few stronger cells/clusters could pose a threat of hail, isolated damaging gusts, and a tornado or two. The magnitude of this threat will be strongly dependent on the extent of diurnal destabilization in the wake of morning convection. Potentially more vigorous redevelopment will be possible along the western/southern periphery of remnant early convection near the ArkLaTex region, where rich moisture and favorable wind profiles will support organized convection, if sufficient recovery/destabilization can occur. Supercells will be possible, though there may be a tendency toward cluster or linear mode as storm coverage increases. Damaging gusts, hail and a few tornadoes will be possible within this regime, though magnitude and favored placement of the threat remain uncertain at this time. ...Northeast OH into PA... A few stronger storms will be possible Sunday afternoon from northeast OH into PA, within a weakly forced northwest-flow regime. At this time, instability appears too weak to support an organized severe threat, though small hail and gusty winds will be possible with the strongest storms. ..Dean.. 04/27/2024
SPC Apr 27, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook
2024-04-27
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Sat Apr 27 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/SOUTH TX INTO THE LOWER MS VALLEY... ...SUMMARY... Isolated strong to severe thunderstorms will be possible on Monday from parts of central and south Texas into the lower Mississippi Valley. ...Synopsis... A shortwave trough initially near the upper Great Lakes region is forecast to gradually weaken and move northeastward on Monday. In its wake, a low-amplitude shortwave trough is forecast to move across the southern Plains. Across the west, a shortwave trough and related mid/upper-level jet will move through the Northwest toward the northern Rockies by Monday evening. ...ArkLaTex into the Lower MS Valley... A storm cluster may be ongoing somewhere near the ArkLaTex region Monday morning, aided by a persistent low-level jet and the approaching low-amplitude shortwave trough. The eastward progression of any such cluster and magnitude of downstream destabilization remain quite uncertain, but some threat for isolated hail, damaging wind, and possibly a tornado could spread into the lower MS Valley through the day. ...Parts of central/south TX... An outflow reinforced front may move into parts of central TX early Monday, in the wake of extensive ongoing convection father east. This front will may stall and either begin moving northward by afternoon, or just become increasingly ill-defined with time. While stronger ascent will move east/northeast of this region, strong heating of a moist airmass will result in moderate to locally strong destabilization, and isolated storm development will be possible. Deep-layer shear will remain sufficient for some storm organization, so any sustained development would pose a threat for hail and isolated severe gusts. ...Parts of the Mid MS and OH Valleys into the lower Great Lakes region... A weakening cold front will move through parts of the Mid MS and OH Valleys during the day on Monday, with the front expected to reach parts of the lower Great Lakes by Monday evening. While moderate deep-layer flow may persist along/ahead of the front, destabilization may be quite limited due to considerable cloudiness and weakening midlevel lapse rates. While a strong storm or two cannot be ruled out along/ahead of the front, uncertainty regarding the development of adequate instability precludes probabilities at this time. ..Dean.. 04/27/2024