WW 159 SEVERE TSTM TX 222015Z - 230400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 159 NWS Storm Prediction Center Norman OK 315 PM CDT Tue Apr 22 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West Texas * Effective this Tuesday afternoon and evening from 315 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 2.5 inches in diameter likely A tornado or two possible SUMMARY...Thunderstorms will develop and increase in coverage through the afternoon and evening across much of west Texas, in an increasingly moist and unstable environment. The strongest cells are expected to produce large hail and damaging wind gusts. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 45 miles northeast of Amarillo TX to 35 miles east of Dryden 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 2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27025. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue Apr 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN/CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms will be possible across parts of the southern/central Plains, mainly this afternoon and evening. Large hail and severe gusts should be the main threats. ...20z Update... The primary change for this forecast update is an inclusion of significant hail/wind areas to portions of western TX into far southwestern OK. Recent GOES visible imagery shows developing cumulus across the Trans Pecos region of southwest TX and across parts of the southern TX Panhandle. This lends confidence in convective development within the coming hours as anticipated by recent high-res guidance. The combination of low-level moisture return and steep/very steep (8-9 C/km) mid-level lapse rates is supporting lifted indices of -8 to -10 C across the Stockton and eastern Edwards plateaus. This thermodynamic environment, coupled with 30-40 knots of effective bulk shear, should favor robust supercell development with the potential for significant (2+ inch) hail. Recent WOFS guidance appears to be capturing ongoing convective trends in southwest TX well, and also hints at this potential. Further north, very steep low-level lapse rates should promote downdraft accelerations that may favor isolated gusts upwards of 70-80 mph. This potential is also hinted in recent WOFS and HRRR solutions. See MCD #516 for additional near-term details regarding western TX. ...Southeast Virginia... Hail/wind risk probabilities are also expanded into far southeast VA downstream of ongoing strong/severe thunderstorms where broken cloud cover has allowed temperatures to warm into the low 80s with an attendant increase in buoyancy. See MCD #515 for additional details. ..Moore.. 04/22/2025 .PREV DISCUSSION... /ISSUED 1117 AM CDT Tue Apr 22 2025/ ...Central/Southern Plains... Morning water vapor imagery shows broad zonal flow across the central US, with the main upper jet across the northern states. Mostly clear skies and southerly low-level winds across much of west TX/OK and central KS will help to destabilize the air mass along a developing dryline, leading to afternoon MLCAPE values around 1500 J/kg and minimal cap. Large scale forcing is weak, but dryline circulations will likely lead to scattered afternoon and early evening thunderstorm development. Relatively slow-moving storms capable of large hail and damaging wind gusts are expected. Several 12z CAM solutions suggest upscale growth of convection over northwest TX after dark, with some risk of strong/severe storms reaching central TX overnight. ...IA/MO/IL... A weak surface boundary extends across southern IA this morning. The southern fringe of stronger westerly flow aloft lies across this region, with water vapor imagery suggesting a subtle shortwave trough over NE approaching the region. A few thunderstorms are expected to form along the boundary by late afternoon/early evening, with some risk of hail and gusty winds in the strongest storms. ...Southeast States... A diffuse surface boundary extends from LA northeastward across MS/AL/GA into the Carolinas. Ample low and mid-level moisture along the boundary will lead to scattered afternoon thunderstorms. Forecast soundings show relatively weak low-level winds and poor mid-level lapse rates. While a few storms could produce gusty winds, organized severe storm risk appears marginal today. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 PM CDT Tue Apr 22 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN KANSAS TO THE TRANSPECOS REGION OF TEXAS... ...SUMMARY... Isolated severe thunderstorms are possible on Thursday from western Texas and Oklahoma into southern Kansas. ...Southern Kansas southwestward to the Transpecos region of Texas... Thunderstorms are forecast to be ongoing at the start of the period near a weak front lying roughly west-to-east across Kansas. As the storms sag southeastward with time, the combined front/convective outflow will continue making slow southward progress. Meanwhile, daytime heating/mixing across the Texas Panhandle/South Plains/Transpecos will support eastward mixing of a dryline through the afternoon. With a moist boundary layer east of the dryline, heating combined with the steep lapse rates/EML being maintained across the area by moderate west-southwesterlies aloft will result in moderate destabilization. This should support isolated storm development near the dryline, perhaps most focused where the southward-sagging outflow/cold front from Kansas intersects the eastward-mixing dryline (somewhere in the southwestern Kansas/northwestern Oklahoma/Texas Panhandle vicinity). The lack of stronger flow aloft should continue to limit shear across the southern Plains region, but veering winds with height should again support potential for mid-level rotation. Attendant risks for large hail and locally gusty/damaging winds warrant continuation of MRGL/5% severe probability. Some thought was given to a small SLGT risk upgrade, near the intersection of the dryline and the outflow-reinforced front mentioned earlier, as backed low-level flow may yield a bit more favorable of a wind profile locally. However, with some uncertainty evident with respect to if, and how far, the front can progress southward through the day, have opted not to upgrade at this time. ..Goss.. 04/22/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...19z Update... Minimal changes were made to the Elevated area across parts of NM. Rainfall has limited the northern and eastern extent of the dry fuels. Additionally, localized dry and breezy conditions are possible over parts of the southern Great Basin. Here, fuels are undergoing drying, but are unlikely to support more than isolated risk for fire-weather concerns for now. Otherwise, no changes were made, see the prior outlook for more info. ..Lyons.. 04/22/2025 .PREV DISCUSSION... /ISSUED 0148 AM CDT Tue Apr 22 2025/ ...Synopsis... Broad cyclonic flow will overspread the western CONUS as modest upper ridging builds over the central and eastern U.S. tomorrow (Wednesday). A weak embedded impulse will traverse the Desert Southwest, encouraging stronger surface flow over portions of eastern Arizona into Far West Texas Wednesday afternoon. Over 15 mph sustained southwesterly surface winds amid 10-15 percent RH will overspread drying fuels, warranting the introduction of Elevated highlights. Meanwhile, in the western Florida Peninsula, strong daytime heating of a dry boundary layer will encourage RH to dip into the 30-40 percent range. Since southeasterly surface winds may reach 10-15 mph atop dry fuels, Elevated highlights were introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0155 PM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...19z Update... Minimal changes were made to the Elevated area across parts of NM. Rainfall has limited the northern and eastern extent of the dry fuels. Additionally, localized dry and breezy conditions are possible over parts of the southern Great Basin. Here, fuels are undergoing drying, but are unlikely to support more than isolated risk for fire-weather concerns for now. Otherwise, no changes were made, see the prior outlook for more info. ..Lyons.. 04/22/2025 .PREV DISCUSSION... /ISSUED 0148 AM CDT Tue Apr 22 2025/ ...Synopsis... Broad cyclonic flow will overspread the western CONUS as modest upper ridging builds over the central and eastern U.S. tomorrow (Wednesday). A weak embedded impulse will traverse the Desert Southwest, encouraging stronger surface flow over portions of eastern Arizona into Far West Texas Wednesday afternoon. Over 15 mph sustained southwesterly surface winds amid 10-15 percent RH will overspread drying fuels, warranting the introduction of Elevated highlights. Meanwhile, in the western Florida Peninsula, strong daytime heating of a dry boundary layer will encourage RH to dip into the 30-40 percent range. Since southeasterly surface winds may reach 10-15 mph atop dry fuels, Elevated highlights were introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Apr 22 18:58:01 UTC 2025.

MD 0514 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF CNTRL/SERN LA...SRN MS...SWRN/CNTRL AL
Mesoscale Discussion 0514 NWS Storm Prediction Center Norman OK 0130 PM CDT Tue Apr 22 2025 Areas affected...parts of cntrl/sern LA...srn MS...swrn/cntrl AL Concerning...Severe potential...Watch unlikely Valid 221830Z - 222130Z Probability of Watch Issuance...5 percent SUMMARY...A gradual increase in thunderstorm activity and intensity appears probable through 4-6 PM CDT, with short-lived stronger storms posing a risk for locally severe hail and wind gusts. DISCUSSION...As low-amplitude mid-level troughing and more subtle smaller-scale perturbations progress through weak (on the order of 10-20 kt) west-southwesterly mean flow across the Gulf Coast states, associated forcing for ascent appears likely to contribute to increasing thunderstorm development through 21-23Z. Inhibition for moist boundary-layer parcels (with dew points near 70F) is becoming increasingly negligible with continuing insolation, with modestly steep lower/mid-tropospheric lapse rates contributing to CAPE around 1500-2000+ J/kg. Despite the rather modest to weak low-level and deep-layer shear, thunderstorms are likely to continue to slowly intensify within the destabilizing environment, into and beyond peak daytime heating. Stronger updraft pulses may eventually pose increasing potential to produce severe hail and damaging downbursts. As convection begins to consolidate and become more widespread, this threat should diminish, but strengthening convective outflow may continue to pose potential for gusty/locally damaging winds into early evening. ..Kerr/Hart.. 04/22/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BMX...MOB...JAN...LIX...LCH...SHV... LAT...LON 33068817 33028748 31578743 30978923 30369057 30979287 31989295 32309176 31969019 33068817 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN NEW MEXICO AND ADJACENT PORTIONS OF THE TEXAS SOUTH PLAINS AND TRANSPECOS REGION... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the central and southern High Plains on Wednesday. ...Central Plains to the southern High Plains... Moderate west-southwesterly flow aloft is forecast aloft across the Plains, with only weak/embedded disturbances within this flow field forecast to shift eastward across the Plains region. Still, with the westerlies aloft maintaining weak lee troughing and potentially a weak low over the southeastern Colorado vicinity, low-level southerlies across the central/southern Plains will maintain a seasonably moist boundary layer. While convection and associated cloud cover ongoing early in the day -- particularly across the central Plains -- may hinder destabilization locally, afternoon insolation should support 1000 to 2000 J/kg mixed-layer CAPE across a fairly broad area. New storm development should occur across the Iowa/Nebraska Kansas area during the afternoon, though location/coverage will likely be modulated by aforementioned/earlier storms and associated outflows. Where ample destabilization occurs, a few clusters of convection capable of producing locally strong/gusty winds and marginal hail can be expected. Greater severe risk -- associated with isolated supercell potential -- remains evident over the southern High Plains area and into the Transpecos region of Texas. Here, a less perturbed airmass should heat/destabilize through the day, ahead of an evolving dryline. With modest but veering flow with height, shear should be sufficient to support mid-level rotation with stronger storms. Large hail and locally damaging gusts will be the main risks with these storms. Some congealing/upscale growth may occur by early evening, as storms spread east-northeastward across parts of western Texas, but overall severe risk should gradually diminish diurnally. ...Parts of the Southeast... A weak mid-level vort max is forecast to be moving eastward across the central Gulf Coast region Wednesday afternoon, where a heating/destabilizing airmass is expected. Fairly steep mid-level lapse rates should be present across the Georgia/South Carolina vicinity, which will contribute to development of 1500 to 2000 J/kg mixed-layer CAPE across this area. While flow aloft will remain relatively weak, and thus storms generally rather disorganized, the degree of CAPE should support a few more vigorous updrafts. Along with potential for marginal hail, a relatively deep mixed layer expected to evolve through peak heating could also promote some evaporative enhancement to downdrafts -- possibly yielding locally strong wind gusts from a few of the stronger storms. Convection -- and any ongoing severe risk -- will diminish after sunset. ..Goss.. 04/22/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN NEW MEXICO AND ADJACENT PORTIONS OF THE TEXAS SOUTH PLAINS AND TRANSPECOS REGION... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the central and southern High Plains on Wednesday. ...Central Plains to the southern High Plains... Moderate west-southwesterly flow aloft is forecast aloft across the Plains, with only weak/embedded disturbances within this flow field forecast to shift eastward across the Plains region. Still, with the westerlies aloft maintaining weak lee troughing and potentially a weak low over the southeastern Colorado vicinity, low-level southerlies across the central/southern Plains will maintain a seasonably moist boundary layer. While convection and associated cloud cover ongoing early in the day -- particularly across the central Plains -- may hinder destabilization locally, afternoon insolation should support 1000 to 2000 J/kg mixed-layer CAPE across a fairly broad area. New storm development should occur across the Iowa/Nebraska Kansas area during the afternoon, though location/coverage will likely be modulated by aforementioned/earlier storms and associated outflows. Where ample destabilization occurs, a few clusters of convection capable of producing locally strong/gusty winds and marginal hail can be expected. Greater severe risk -- associated with isolated supercell potential -- remains evident over the southern High Plains area and into the Transpecos region of Texas. Here, a less perturbed airmass should heat/destabilize through the day, ahead of an evolving dryline. With modest but veering flow with height, shear should be sufficient to support mid-level rotation with stronger storms. Large hail and locally damaging gusts will be the main risks with these storms. Some congealing/upscale growth may occur by early evening, as storms spread east-northeastward across parts of western Texas, but overall severe risk should gradually diminish diurnally. ...Parts of the Southeast... A weak mid-level vort max is forecast to be moving eastward across the central Gulf Coast region Wednesday afternoon, where a heating/destabilizing airmass is expected. Fairly steep mid-level lapse rates should be present across the Georgia/South Carolina vicinity, which will contribute to development of 1500 to 2000 J/kg mixed-layer CAPE across this area. While flow aloft will remain relatively weak, and thus storms generally rather disorganized, the degree of CAPE should support a few more vigorous updrafts. Along with potential for marginal hail, a relatively deep mixed layer expected to evolve through peak heating could also promote some evaporative enhancement to downdrafts -- possibly yielding locally strong wind gusts from a few of the stronger storms. Convection -- and any ongoing severe risk -- will diminish after sunset. ..Goss.. 04/22/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Tue Apr 22 2025 Valid 221630Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN/CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms will be possible across parts of the southern/central Plains, mainly this afternoon and evening. Large hail and severe gusts should be the main threats. ...Central/Southern Plains... Morning water vapor imagery shows broad zonal flow across the central US, with the main upper jet across the northern states. Mostly clear skies and southerly low-level winds across much of west TX/OK and central KS will help to destabilize the air mass along a developing dryline, leading to afternoon MLCAPE values around 1500 J/kg and minimal cap. Large scale forcing is weak, but dryline circulations will likely lead to scattered afternoon and early evening thunderstorm development. Relatively slow-moving storms capable of large hail and damaging wind gusts are expected. Several 12z CAM solutions suggest upscale growth of convection over northwest TX after dark, with some risk of strong/severe storms reaching central TX overnight. ...IA/MO/IL... A weak surface boundary extends across southern IA this morning. The southern fringe of stronger westerly flow aloft lies across this region, with water vapor imagery suggesting a subtle shortwave trough over NE approaching the region. A few thunderstorms are expected to form along the boundary by late afternoon/early evening, with some risk of hail and gusty winds in the strongest storms. ...Southeast States... A diffuse surface boundary extends from LA northeastward across MS/AL/GA into the Carolinas. Ample low and mid-level moisture along the boundary will lead to scattered afternoon thunderstorms. Forecast soundings show relatively weak low-level winds and poor mid-level lapse rates. While a few storms could produce gusty winds, organized severe storm risk appears marginal today. ..Hart/Thornton.. 04/22/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1118 AM CDT Tue Apr 22 2025 Valid 221700Z - 231200Z ...NO CRITICAL AREAS... ...16z Update... No changes, benign fire-weather conditions are expected today and tonight. See the prior outlook for more information. ..Lyons.. 04/22/2025 .PREV DISCUSSION... /ISSUED 0136 AM CDT Tue Apr 22 2025/ ...Synopsis... The upper-air pattern will be characterized by mainly zonal flow with embedded perturbations across the northern half of the CONUS today. This pattern will support a modest westerly surface wind field across the northern Plains and over portions of the Northeast this afternoon. Given marginally supportive RH over the northern Plains and Northeast, wildfire spread concerns should remain localized, especially wherever dry fuel beds exist. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Tue Apr 22 13:15:01 UTC 2025.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Tue Apr 22 2025 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN/CENTRAL PLAINS... ...SUMMARY... Isolated to scattered severe thunderstorms will be possible across parts of the southern/central Plains, mainly this afternoon and evening. Large hail and severe gusts should be the main threats. ...Southern/Central Plains... Stronger westerly flow aloft should remain confined to the northern tier of the CONUS today, and to the north of the surface warm sector. Multiple weak mid-level disturbances may drift eastward across the southern/central High Plains through this evening, with fairly modest mid-level flow for late April standards. At the surface, a front will extend from parts of the Upper Midwest to southwest KS near a weak surface low. A dryline will extend southward from this low over the southern High Plains. Some eastward mixing of the dryline is forecast by late afternoon, especially across the OK/TX Panhandles. Otherwise, little movement of the front is anticipated through this evening. Both of these surface boundaries should provide some focus for convective development this afternoon and evening, even with large-scale forcing for ascent remaining rather nebulous. Weak to locally moderate instability should develop through the afternoon with diurnal heating of a partially modified Gulf airmass. Even though west-southwesterly mid-level flow is expected to remain fairly modest, weak low-level winds gradually veering/strengthening with height though mid/upper levels should support sufficient deep-layer shear for some updraft organization. A mix of widely spaced supercells and multicells may eventually develop along both the front and dryline, with uncertainty remaining rather high about favored locations for robust convective development. Regardless, this activity could pose a threat for isolated to scattered large hail given steep lapse rates aloft. Any clusters that can evolve through the late afternoon and evening may also have some severe wind threat given steep low-level lapse rates. Some trimming was made to the northwest extent of severe probabilities based on the forecast position of the front/dryline later today. ...Southeast to the Carolinas... A weak front draped southwest to northeast is forecast to move little today across the Southeast. Generally modest west-southwesterly mid-level flow is expected to prevail, with slightly stronger winds aloft forecast over the Carolinas. This should tend to limit deep-layer shear and convective organization/intensity. Still, with some destabilization forecast and fairly cool temperatures aloft, any clusters of convection that can develop along/south of the front may pose an isolated threat for damaging winds and perhaps marginally severe hail. Based on latest observational and guidance trends showing greater thunderstorm coverage this afternoon across parts of AL into northern GA, have connected the two Marginal Risk areas with this update. ..Gleason/Broyles.. 04/22/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Tue Apr 22 2025 Valid 251200Z - 301200Z ...DISCUSSION... ...Days 4-5/Fri-Sat -- Central/Southern Plains... An upper ridge will build over the Plains toward the MS Valley this weekend as a deepening upper trough develops over the western U.S. Some lead shortwave impulses will likely migrate through the ridge, and southwesterly flow increases over the central/southern Rockies. At the surface, persistent south/southeasterly low-level flow will maintain a warm advection regime across the southern/central Plains, while a daily surface dryline evolves over the High Plains. While some severe potential may occur Friday and Saturday over parts the central/southern Plains, uncertainty remains quite high given several periods of convection leading into Friday, as well as ongoing convection Friday morning, and possible capping concerns beneath the upper ridge both days. This precludes 15 percent probability delineation at this time, but probabilities may be needed in subsequent outlooks as smaller scale details become better resolved. ...Days 6-8/Sun-Tue -- Great Plains to the Upper Midwest... A more active severe weather period is possible early next week as the western U.S. trough develops eastward into the Plains and Great Lakes vicinity. The upper trough may begin ejecting into the southern/central Plains as early as Day 6/Sun. However, the timing of this feature may be ill-timed with peak diurnal heating/destabilization such that stronger large-scale ascent and increasing southwesterly flow aloft arrive overnight. Forecast soundings Sunday afternoon suggest capping may limit convection. By Day 7/Mon, a strong midlevel jet streak should overspread portions of the central/southern Plains into the Upper Midwest. Lee cyclogenesis is forecast across the central High Plains, resulting in a sharpening dryline across portions of the Great Plains, and warm front extending across the eastern Dakotas to the Mid-MS Valley. Rich Gulf moisture will be in place across the warm sector and widely scattered severe storms appear possible from Monday afternoon into Monday night. As is typical at longer time frames, forecast guidance differs in exact timing and placement of key features. However, the overall pattern is favorable for an all-hazards severe weather episode, and a 15 percent delineation has been included, though this area may shift over the coming days as details become better resolved. Severe potential may continue into Day 8/Tue across portions of the Midwest to the southern Plains as a shortwave upper trough continues across the Great Lakes into southeast Canada, and a cold front impinges southeastward over portions of the region. Uncertainty increases considerably during this time, precluding 15 percent probabilities at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Tue Apr 22 2025 Valid 251200Z - 301200Z ...DISCUSSION... ...Days 4-5/Fri-Sat -- Central/Southern Plains... An upper ridge will build over the Plains toward the MS Valley this weekend as a deepening upper trough develops over the western U.S. Some lead shortwave impulses will likely migrate through the ridge, and southwesterly flow increases over the central/southern Rockies. At the surface, persistent south/southeasterly low-level flow will maintain a warm advection regime across the southern/central Plains, while a daily surface dryline evolves over the High Plains. While some severe potential may occur Friday and Saturday over parts the central/southern Plains, uncertainty remains quite high given several periods of convection leading into Friday, as well as ongoing convection Friday morning, and possible capping concerns beneath the upper ridge both days. This precludes 15 percent probability delineation at this time, but probabilities may be needed in subsequent outlooks as smaller scale details become better resolved. ...Days 6-8/Sun-Tue -- Great Plains to the Upper Midwest... A more active severe weather period is possible early next week as the western U.S. trough develops eastward into the Plains and Great Lakes vicinity. The upper trough may begin ejecting into the southern/central Plains as early as Day 6/Sun. However, the timing of this feature may be ill-timed with peak diurnal heating/destabilization such that stronger large-scale ascent and increasing southwesterly flow aloft arrive overnight. Forecast soundings Sunday afternoon suggest capping may limit convection. By Day 7/Mon, a strong midlevel jet streak should overspread portions of the central/southern Plains into the Upper Midwest. Lee cyclogenesis is forecast across the central High Plains, resulting in a sharpening dryline across portions of the Great Plains, and warm front extending across the eastern Dakotas to the Mid-MS Valley. Rich Gulf moisture will be in place across the warm sector and widely scattered severe storms appear possible from Monday afternoon into Monday night. As is typical at longer time frames, forecast guidance differs in exact timing and placement of key features. However, the overall pattern is favorable for an all-hazards severe weather episode, and a 15 percent delineation has been included, though this area may shift over the coming days as details become better resolved. Severe potential may continue into Day 8/Tue across portions of the Midwest to the southern Plains as a shortwave upper trough continues across the Great Lakes into southeast Canada, and a cold front impinges southeastward over portions of the region. Uncertainty increases considerably during this time, precluding 15 percent probabilities at this time. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Tue Apr 22 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN TEXAS AND OKLAHOMA INTO SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Thursday from western Texas and Oklahoma into southern Kansas. ...Southern/Central Plains... The low-amplitude, modest southwesterly flow regime will continue across the Plains on Thursday. Some guidance suggests a modest shortwave upper trough will migrate across the southern Rockies into the southern Plains Thursday afternoon. This will support weak lee troughing across the central/southern High Plains, and a dryline will likely develop from the OK/TX Panhandles into southwest TX. Meanwhile, a stalled frontal boundary from IA into western KS will slowly sag southward late in the afternoon into the nighttime hours. Southerly low-level flow will maintain 60s F dewpoints across a broad warm sector, and weak to moderate destabilization is expected across parts of TX/OK and southern KS. Some convection may be ongoing Thursday morning, resulting in uncertainty regarding where better destabilization will occur. Nevertheless, isolated severe thunderstorms will be possible along the dryline and potentially any outflow boundaries from prior convection, providing a risk for large hail and strong gusts. ..Leitman.. 04/22/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0148 AM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...Synopsis... Broad cyclonic flow will overspread the western CONUS as modest upper ridging builds over the central and eastern U.S. tomorrow (Wednesday). A weak embedded impulse will traverse the Desert Southwest, encouraging stronger surface flow over portions of eastern Arizona into Far West Texas Wednesday afternoon. Over 15 mph sustained southwesterly surface winds amid 10-15 percent RH will overspread drying fuels, warranting the introduction of Elevated highlights. Meanwhile, in the western Florida Peninsula, strong daytime heating of a dry boundary layer will encourage RH to dip into the 30-40 percent range. Since southeasterly surface winds may reach 10-15 mph atop dry fuels, Elevated highlights were introduced. ..Squitieri.. 04/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0136 AM CDT Tue Apr 22 2025 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... The upper-air pattern will be characterized by mainly zonal flow with embedded perturbations across the northern half of the CONUS today. This pattern will support a modest westerly surface wind field across the northern Plains and over portions of the Northeast this afternoon. Given marginally supportive RH over the northern Plains and Northeast, wildfire spread concerns should remain localized, especially wherever dry fuel beds exist. ..Squitieri.. 04/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the central and southern High Plains on Wednesday. ...Central/Southern Plains... A low-amplitude, modest southwesterly flow regime will persist across the Plains on Wednesday. At the surface, a stalled frontal boundary will extend from the Upper Midwest to the central High Plains, while a dryline extends south from southeast CO into southwest TX. Southerly low-level flow will maintain northward transport of modified Gulf moisture across TX/OK into the central Plains. Forecast guidance varies considerably regarding ongoing precipitation Wednesday morning. Some CAMs show widespread convection across KS, while other place morning convection further south along the Red River. This morning convection will potentially have implications for afternoon/evening severe potential as it may hinder diurnal destabilization, or produce outflow boundaries which could aid in redevelopment later in the day. Nevertheless, adequate boundary layer moisture beneath steep midlevel lapse rates and modest vertical shear (25-35 kt effective shear magnitudes) will support a broad area of at least Marginal (level 1 of 5) severe risk (strong winds and hail) from the central Plains along the stalled frontal boundary, south/southwest into the southern High Plains along the dry line. Some greater risk for a few supercells may develop along the dryline across west Texas. Stronger heating and higher surface dewpoints will foster greater destabilization. Elongated hodographs suggest isolated supercells capable of producing large hail will be possible. Furthermore, steep low-level lapse rates and deep boundary layer mixing may support sporadic strong/severe gusts. Given nebulous/weak large-scale ascent, storm coverage along the dryline is uncertain, and probabilities may need to be adjusted/extended northward if confidence increases in greater storm coverage. ..Leitman.. 04/22/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Apr 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the central and southern High Plains on Wednesday. ...Central/Southern Plains... A low-amplitude, modest southwesterly flow regime will persist across the Plains on Wednesday. At the surface, a stalled frontal boundary will extend from the Upper Midwest to the central High Plains, while a dryline extends south from southeast CO into southwest TX. Southerly low-level flow will maintain northward transport of modified Gulf moisture across TX/OK into the central Plains. Forecast guidance varies considerably regarding ongoing precipitation Wednesday morning. Some CAMs show widespread convection across KS, while other place morning convection further south along the Red River. This morning convection will potentially have implications for afternoon/evening severe potential as it may hinder diurnal destabilization, or produce outflow boundaries which could aid in redevelopment later in the day. Nevertheless, adequate boundary layer moisture beneath steep midlevel lapse rates and modest vertical shear (25-35 kt effective shear magnitudes) will support a broad area of at least Marginal (level 1 of 5) severe risk (strong winds and hail) from the central Plains along the stalled frontal boundary, south/southwest into the southern High Plains along the dry line. Some greater risk for a few supercells may develop along the dryline across west Texas. Stronger heating and higher surface dewpoints will foster greater destabilization. Elongated hodographs suggest isolated supercells capable of producing large hail will be possible. Furthermore, steep low-level lapse rates and deep boundary layer mixing may support sporadic strong/severe gusts. Given nebulous/weak large-scale ascent, storm coverage along the dryline is uncertain, and probabilities may need to be adjusted/extended northward if confidence increases in greater storm coverage. ..Leitman.. 04/22/2025 Read more