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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0323 AM CDT Sun Apr 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... A low-amplitude southwesterly flow regime will prevail for much of the Day 4-8 period across portions of the central and eastern U.S., with a mean upper trough persisting across the western states. Persistent south/southeasterly low-level flow across the Gulf and southern Plains will result in northward transport of rich boundary-layer moisture across the southern and parts of the central Plains through at least Day 6/Fri. Forecast guidance suggests weak shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to scattered thunderstorm potential across the warm sector over TX/OK/KS. Given a moist and unstable airmass, at least some severe potential will exist. However, where exactly severe potential may develop Day 4-5/Wed-Thu is uncertain given a lack of stronger large-scale ascent and absence of any substantial surface cyclogenesis, coupled with modest deep-layer flow. This precludes 15 percent probabilities at this time, though outlook areas could become necessary in later outlooks as smaller-scale features become better resolved. A period of weak upper ridging may spread across the Plains and the eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper trough developing over the western U.S. This may limit severe potential late in the week before the western upper trough ejects east toward the end of the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0323 AM CDT Sun Apr 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... A low-amplitude southwesterly flow regime will prevail for much of the Day 4-8 period across portions of the central and eastern U.S., with a mean upper trough persisting across the western states. Persistent south/southeasterly low-level flow across the Gulf and southern Plains will result in northward transport of rich boundary-layer moisture across the southern and parts of the central Plains through at least Day 6/Fri. Forecast guidance suggests weak shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to scattered thunderstorm potential across the warm sector over TX/OK/KS. Given a moist and unstable airmass, at least some severe potential will exist. However, where exactly severe potential may develop Day 4-5/Wed-Thu is uncertain given a lack of stronger large-scale ascent and absence of any substantial surface cyclogenesis, coupled with modest deep-layer flow. This precludes 15 percent probabilities at this time, though outlook areas could become necessary in later outlooks as smaller-scale features become better resolved. A period of weak upper ridging may spread across the Plains and the eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper trough developing over the western U.S. This may limit severe potential late in the week before the western upper trough ejects east toward the end of the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0323 AM CDT Sun Apr 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... A low-amplitude southwesterly flow regime will prevail for much of the Day 4-8 period across portions of the central and eastern U.S., with a mean upper trough persisting across the western states. Persistent south/southeasterly low-level flow across the Gulf and southern Plains will result in northward transport of rich boundary-layer moisture across the southern and parts of the central Plains through at least Day 6/Fri. Forecast guidance suggests weak shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to scattered thunderstorm potential across the warm sector over TX/OK/KS. Given a moist and unstable airmass, at least some severe potential will exist. However, where exactly severe potential may develop Day 4-5/Wed-Thu is uncertain given a lack of stronger large-scale ascent and absence of any substantial surface cyclogenesis, coupled with modest deep-layer flow. This precludes 15 percent probabilities at this time, though outlook areas could become necessary in later outlooks as smaller-scale features become better resolved. A period of weak upper ridging may spread across the Plains and the eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper trough developing over the western U.S. This may limit severe potential late in the week before the western upper trough ejects east toward the end of the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0323 AM CDT Sun Apr 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... A low-amplitude southwesterly flow regime will prevail for much of the Day 4-8 period across portions of the central and eastern U.S., with a mean upper trough persisting across the western states. Persistent south/southeasterly low-level flow across the Gulf and southern Plains will result in northward transport of rich boundary-layer moisture across the southern and parts of the central Plains through at least Day 6/Fri. Forecast guidance suggests weak shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to scattered thunderstorm potential across the warm sector over TX/OK/KS. Given a moist and unstable airmass, at least some severe potential will exist. However, where exactly severe potential may develop Day 4-5/Wed-Thu is uncertain given a lack of stronger large-scale ascent and absence of any substantial surface cyclogenesis, coupled with modest deep-layer flow. This precludes 15 percent probabilities at this time, though outlook areas could become necessary in later outlooks as smaller-scale features become better resolved. A period of weak upper ridging may spread across the Plains and the eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper trough developing over the western U.S. This may limit severe potential late in the week before the western upper trough ejects east toward the end of the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0323 AM CDT Sun Apr 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... A low-amplitude southwesterly flow regime will prevail for much of the Day 4-8 period across portions of the central and eastern U.S., with a mean upper trough persisting across the western states. Persistent south/southeasterly low-level flow across the Gulf and southern Plains will result in northward transport of rich boundary-layer moisture across the southern and parts of the central Plains through at least Day 6/Fri. Forecast guidance suggests weak shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to scattered thunderstorm potential across the warm sector over TX/OK/KS. Given a moist and unstable airmass, at least some severe potential will exist. However, where exactly severe potential may develop Day 4-5/Wed-Thu is uncertain given a lack of stronger large-scale ascent and absence of any substantial surface cyclogenesis, coupled with modest deep-layer flow. This precludes 15 percent probabilities at this time, though outlook areas could become necessary in later outlooks as smaller-scale features become better resolved. A period of weak upper ridging may spread across the Plains and the eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper trough developing over the western U.S. This may limit severe potential late in the week before the western upper trough ejects east toward the end of the forecast period. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0150 Status Updates
STATUS REPORT ON WW 150 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW BWD TO 15 SSW SPS. ..BROYLES..04/20/25 ATTN...WFO...OUN...MAF...SJT...LUB...FWD... STATUS REPORT FOR WS 150 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC059-429-503-200840- TX . TEXAS COUNTIES INCLUDED ARE CALLAHAN STEPHENS YOUNG THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 150 SEVERE TSTM TX 200250Z - 201000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 150 NWS Storm Prediction Center Norman OK 950 PM CDT Sat Apr 19 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West into Northwest Texas * Effective this Saturday night and Sunday morning from 950 PM until 500 AM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...A intensifying band of thunderstorms is forecast to move from west to east across the Watch area tonight. Large hail and severe gusts are possible with the more intense thunderstorms. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 80 miles northeast of Abilene TX to 15 miles northwest of Midland TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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 147...WW 148...WW 149... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26035. ...Smith Read more

WW 0151 Status Updates
STATUS REPORT ON WW 151 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NE DRT TO 10 W JCT TO 15 WNW BWD. ..BROYLES..04/20/25 ATTN...WFO...SJT...EWX... STATUS REPORT FOR WT 151 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC049-083-137-171-265-267-299-307-319-327-411-200840- TX . TEXAS COUNTIES INCLUDED ARE BROWN COLEMAN EDWARDS GILLESPIE KERR KIMBLE LLANO MCCULLOCH MASON MENARD SAN SABA THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0153 Status Updates
STATUS FOR WATCH 0153 HAS NOT BEEN ISSUED YET Read more

MD 0498 CONCERNING TORNADO WATCH 152... FOR EASTERN OKLAHOMA...NORTHWEST ARKANSAS...FAR SOUTHWEST MISSOURI
Mesoscale Discussion 0498 NWS Storm Prediction Center Norman OK 0122 AM CDT Sun Apr 20 2025 Areas affected...Eastern Oklahoma...Northwest Arkansas...Far Southwest Missouri Concerning...Tornado Watch 152... Valid 200622Z - 200715Z The severe weather threat for Tornado Watch 152 continues. SUMMARY...A threat for severe wind gusts and tornadoes will move across eastern Oklahoma and into northwest Arkansas over the next few hours. The threat is expected to eventually affect far southwest Missouri, where weather watch issuance is possible. DISCUSSION...The latest hi-resolution radar imagery from Tulsa shows a north-to-south oriented severe line segment across eastern Oklahoma. Ahead of the line, surface dewpoints are in the 60s F. Near the moist axis, an axis of instability is analyzed by the RAP with MLCAPE around 1000 J/kg range. Co-located with the instability axis, the RAP is analyzing a 50 to 60 knot 700 mb jet from northeast Texas into southeast Oklahoma. This line of storms is located near the nose of this jet max. Short-term model forecasts strengthen the jet max and move it into eastern Oklahoma over the next few hours. This will provide lift and strong shear favorable for severe maintenance. The latest WSR-88D VWP from Fort Smith has 0-6 km shear around 65 knots, with 0-3 km storm-relative helicity near 550 m2/s2. This will continue to support a QLCS with embedded rotating elements. These stronger storms will be associated with severe wind gusts, and potentially tornadoes. The threat is expected to persist for several more hours. The line should eventually move into northwest Arkansas and far southwest Missouri where instability will be more limited. ..Broyles.. 04/20/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...SHV...TSA...OUN... LAT...LON 36759496 36469540 36109556 35429576 34399591 34119581 34019538 34419453 35089380 35649329 35999305 36279305 36629323 36809384 36759496 MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Sun Apr 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF WESTERN/CENTRAL TEXAS...WESTERN OKLAHOMA...AND SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the southern Plains. ...Synopsis... A low-amplitude west/southwest flow regime is expected across much of the CONUS on Tuesday. A weak upper trough will be maintained across the western U.S. while a belt of stronger westerly flow envelops the north-central and northeast U.S. where a pair of modest shortwave upper troughs will migrate east through the period. At the surface, south/southeasterly low-level flow over the Gulf and southern Plains will transport modified Gulf moisture northward across TX/OK/KS. ...Western TX/OK into southern KS... Large scale ascent is expected to remain somewhat nebulous across the region on Tuesday. However, various forecast models suggest a weak impulse may migrate across the southern Rockies into the southern Plains Tuesday afternoon into evening atop the moistening boundary layer. Modest west/southwesterly flow and strong surface heating also may allow for weak lee low development across the southern High Plains, and the development of a dryline extending from the OK/TX Panhandles southward through western TX. A stalled surface boundary is also forecast to extend across central KS. These boundaries may provide focus for isolated thunderstorm development by late afternoon. A plume of steep midlevel lapse rates will reside across the region, aiding in diurnal destabilization, with MLCAPE values around 1500-2000 J/kg possible. Additionally, forecast guidance indicates an 25-35 kt southwesterly low-level jet will develop during the evening. NAM forecast soundings suggest at least weak capping between 850-700 mb may persist, though the GFS is much more mixed with a weaker cap. Given the weak forcing regime, thunderstorm coverage remains uncertain. Nevertheless, a few organized thunderstorms during the late afternoon into the evening hours, with a risk for large hail and damaging gusts, appear possible and a Marginal (level 1 of 5) risk has been included. ..Leitman.. 04/20/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Sun Apr 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF WESTERN/CENTRAL TEXAS...WESTERN OKLAHOMA...AND SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the southern Plains. ...Synopsis... A low-amplitude west/southwest flow regime is expected across much of the CONUS on Tuesday. A weak upper trough will be maintained across the western U.S. while a belt of stronger westerly flow envelops the north-central and northeast U.S. where a pair of modest shortwave upper troughs will migrate east through the period. At the surface, south/southeasterly low-level flow over the Gulf and southern Plains will transport modified Gulf moisture northward across TX/OK/KS. ...Western TX/OK into southern KS... Large scale ascent is expected to remain somewhat nebulous across the region on Tuesday. However, various forecast models suggest a weak impulse may migrate across the southern Rockies into the southern Plains Tuesday afternoon into evening atop the moistening boundary layer. Modest west/southwesterly flow and strong surface heating also may allow for weak lee low development across the southern High Plains, and the development of a dryline extending from the OK/TX Panhandles southward through western TX. A stalled surface boundary is also forecast to extend across central KS. These boundaries may provide focus for isolated thunderstorm development by late afternoon. A plume of steep midlevel lapse rates will reside across the region, aiding in diurnal destabilization, with MLCAPE values around 1500-2000 J/kg possible. Additionally, forecast guidance indicates an 25-35 kt southwesterly low-level jet will develop during the evening. NAM forecast soundings suggest at least weak capping between 850-700 mb may persist, though the GFS is much more mixed with a weaker cap. Given the weak forcing regime, thunderstorm coverage remains uncertain. Nevertheless, a few organized thunderstorms during the late afternoon into the evening hours, with a risk for large hail and damaging gusts, appear possible and a Marginal (level 1 of 5) risk has been included. ..Leitman.. 04/20/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Sun Apr 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF WESTERN/CENTRAL TEXAS...WESTERN OKLAHOMA...AND SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the southern Plains. ...Synopsis... A low-amplitude west/southwest flow regime is expected across much of the CONUS on Tuesday. A weak upper trough will be maintained across the western U.S. while a belt of stronger westerly flow envelops the north-central and northeast U.S. where a pair of modest shortwave upper troughs will migrate east through the period. At the surface, south/southeasterly low-level flow over the Gulf and southern Plains will transport modified Gulf moisture northward across TX/OK/KS. ...Western TX/OK into southern KS... Large scale ascent is expected to remain somewhat nebulous across the region on Tuesday. However, various forecast models suggest a weak impulse may migrate across the southern Rockies into the southern Plains Tuesday afternoon into evening atop the moistening boundary layer. Modest west/southwesterly flow and strong surface heating also may allow for weak lee low development across the southern High Plains, and the development of a dryline extending from the OK/TX Panhandles southward through western TX. A stalled surface boundary is also forecast to extend across central KS. These boundaries may provide focus for isolated thunderstorm development by late afternoon. A plume of steep midlevel lapse rates will reside across the region, aiding in diurnal destabilization, with MLCAPE values around 1500-2000 J/kg possible. Additionally, forecast guidance indicates an 25-35 kt southwesterly low-level jet will develop during the evening. NAM forecast soundings suggest at least weak capping between 850-700 mb may persist, though the GFS is much more mixed with a weaker cap. Given the weak forcing regime, thunderstorm coverage remains uncertain. Nevertheless, a few organized thunderstorms during the late afternoon into the evening hours, with a risk for large hail and damaging gusts, appear possible and a Marginal (level 1 of 5) risk has been included. ..Leitman.. 04/20/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Sun Apr 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF WESTERN/CENTRAL TEXAS...WESTERN OKLAHOMA...AND SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the southern Plains. ...Synopsis... A low-amplitude west/southwest flow regime is expected across much of the CONUS on Tuesday. A weak upper trough will be maintained across the western U.S. while a belt of stronger westerly flow envelops the north-central and northeast U.S. where a pair of modest shortwave upper troughs will migrate east through the period. At the surface, south/southeasterly low-level flow over the Gulf and southern Plains will transport modified Gulf moisture northward across TX/OK/KS. ...Western TX/OK into southern KS... Large scale ascent is expected to remain somewhat nebulous across the region on Tuesday. However, various forecast models suggest a weak impulse may migrate across the southern Rockies into the southern Plains Tuesday afternoon into evening atop the moistening boundary layer. Modest west/southwesterly flow and strong surface heating also may allow for weak lee low development across the southern High Plains, and the development of a dryline extending from the OK/TX Panhandles southward through western TX. A stalled surface boundary is also forecast to extend across central KS. These boundaries may provide focus for isolated thunderstorm development by late afternoon. A plume of steep midlevel lapse rates will reside across the region, aiding in diurnal destabilization, with MLCAPE values around 1500-2000 J/kg possible. Additionally, forecast guidance indicates an 25-35 kt southwesterly low-level jet will develop during the evening. NAM forecast soundings suggest at least weak capping between 850-700 mb may persist, though the GFS is much more mixed with a weaker cap. Given the weak forcing regime, thunderstorm coverage remains uncertain. Nevertheless, a few organized thunderstorms during the late afternoon into the evening hours, with a risk for large hail and damaging gusts, appear possible and a Marginal (level 1 of 5) risk has been included. ..Leitman.. 04/20/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Sun Apr 20 2025 Valid 221200Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF WESTERN/CENTRAL TEXAS...WESTERN OKLAHOMA...AND SOUTHERN KANSAS... ...SUMMARY... Isolated severe thunderstorms are possible on Tuesday across portions of the southern Plains. ...Synopsis... A low-amplitude west/southwest flow regime is expected across much of the CONUS on Tuesday. A weak upper trough will be maintained across the western U.S. while a belt of stronger westerly flow envelops the north-central and northeast U.S. where a pair of modest shortwave upper troughs will migrate east through the period. At the surface, south/southeasterly low-level flow over the Gulf and southern Plains will transport modified Gulf moisture northward across TX/OK/KS. ...Western TX/OK into southern KS... Large scale ascent is expected to remain somewhat nebulous across the region on Tuesday. However, various forecast models suggest a weak impulse may migrate across the southern Rockies into the southern Plains Tuesday afternoon into evening atop the moistening boundary layer. Modest west/southwesterly flow and strong surface heating also may allow for weak lee low development across the southern High Plains, and the development of a dryline extending from the OK/TX Panhandles southward through western TX. A stalled surface boundary is also forecast to extend across central KS. These boundaries may provide focus for isolated thunderstorm development by late afternoon. A plume of steep midlevel lapse rates will reside across the region, aiding in diurnal destabilization, with MLCAPE values around 1500-2000 J/kg possible. Additionally, forecast guidance indicates an 25-35 kt southwesterly low-level jet will develop during the evening. NAM forecast soundings suggest at least weak capping between 850-700 mb may persist, though the GFS is much more mixed with a weaker cap. Given the weak forcing regime, thunderstorm coverage remains uncertain. Nevertheless, a few organized thunderstorms during the late afternoon into the evening hours, with a risk for large hail and damaging gusts, appear possible and a Marginal (level 1 of 5) risk has been included. ..Leitman.. 04/20/2025 Read more