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WW 0302 Status Updates
STATUS REPORT ON WW 302 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NNE TYS TO 35 SSE JKL TO 25 ENE JKL TO 25 W HTS. ..KERR..05/20/25 ATTN...WFO...JKL...LMK...RLX...MRX...OHX... STATUS REPORT FOR WT 302 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KYC019-043-071-089-115-119-127-133-159-195-202140- KY . KENTUCKY COUNTIES INCLUDED ARE BOYD CARTER FLOYD GREENUP JOHNSON KNOTT LAWRENCE LETCHER MARTIN PIKE TNC057-063-067-073-163-202140- TN . TENNESSEE COUNTIES INCLUDED ARE GRAINGER HAMBLEN HANCOCK HAWKINS SULLIVAN VAC027-051-105-167-169-191-195-520-720-202140- VA . VIRGINIA COUNTIES INCLUDED ARE Read more

MD 0904 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN TEXAS INTO NORTHERN LOUISIANA
Mesoscale Discussion 0904 NWS Storm Prediction Center Norman OK 0114 PM CDT Tue May 20 2025 Areas affected...Eastern Texas into northern Louisiana Concerning...Severe potential...Watch possible Valid 201814Z - 202015Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms developing along a cold front across eastern Texas will likely pose a severe threat through late afternoon downstream into northern Louisiana. Watch issuance is possible as storm coverage becomes more clear in the next couple of hours. DISCUSSION...A focused band of ascent is evident in recent GOES imagery across east TX along an eastward moving cold front. KSHV and KPOE have recently sampled a couple of deeper convective towers with echo tops reaching up to 15-20 kft, suggesting that the probability for deep convective initiation is steadily increasing. Further heating of a very moist environment ahead of the front over the next couple of hours will continue to erode inhibition and promote thunderstorm development by around 19-21 UTC. While eastern TX/LA is on the southern periphery of the stronger mid-level jet core to the north across AR, 40-50 knot mid-level flow atop weak low-level winds will still support elongated, nearly-straight hodographs. This thermodynamic/kinematic environment will support splitting supercells with an attendant risk for severe gusts and large to very large hail (possibly as high as 1.5 to 2.5 inches). Modest warm-air advection across northern LA is currently supporting sufficient low-level veering for around 100-150 m2/s2 0-1 km SRH, which could support some tornado risk. However, flow within this layer is expected to become more uni-directional through late afternoon, so it is unclear if storms will intensify and migrate into the favorably sheared environment before low-level helicity wanes. Additionally, displacement from the stronger broad-scale ascent to the north casts some uncertainty on convective coverage through the afternoon. Watch issuance will likely be needed if a sufficiently widespread threat becomes apparent. ..Moore/Hart.. 05/20/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...JAN...LCH...SHV...HGX... LAT...LON 32179129 30899339 30619415 30579469 30759515 31119531 31339529 31539514 32619381 32879347 33019312 33049221 33019121 32739109 32459106 32179129 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

WW 0306 Status Updates
STATUS FOR WATCH 0306 HAS NOT BEEN ISSUED YET Read more

WW 0306 Status Updates
STATUS FOR WATCH 0306 HAS NOT BEEN ISSUED YET Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue May 20 2025 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID MS VALLEY TO THE CENTRAL APPALACHIANS... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...20Z Update... Much of the previous forecast remains on track. Earlier storms across the TN Valley have matured into a QLCS, which is now approaching the central Appalachians. These storms should progress toward the eastern extent of a buoyant warm sector with a continued risk of damaging gusts and perhaps a couple of tornadoes. Storms poised to cross the MS River over the central MS Valley, and more discrete storms farther east over western TN/northern MS, should intensify further as they move eastward amid a strongly sheared and unstable airmass. The more intense, discrete storms will be capable of large to very large hail and at least isolated tornadoes. The more dominant supercells that move into northeast MS, middle TN, and southern KY, where surface is flow is relatively more backed, will have the best chance at producing a strong tornado. Lastly, storms should continue to intensify ahead of a surface low over central IL and immediate surrounding areas. Shear/buoyancy over this region favors supercell structures with a continued large hail/tornado risk. ..Squitieri.. 05/20/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Tue May 20 2025/ ...KY/TN... Thunderstorms are ongoing across central KY/middle TN. These storms will progress eastward through the afternoon into a moist and increasingly unstable air mass over eastern KY/TN and eventually into western WV/VA. Most model guidance suggests that storms will intensify through the day, with an increasing risk of damaging wind gusts and a few tornadoes. Refer to MCD #902 for further details. ...AR into the TN Valley this afternoon/evening... In the wake of the aforementioned convection, rapid heating is occurring across eastern AR/west TN/northern MS. Surface dewpoints in the upper 60s to 70s and steep mid level lapse rates will yield afternoon MLCAPE values around 3000 J/kg and only a weak cap. This will lead to the development of multiple clusters of intense thunderstorms (including supercells) that will track eastward through the afternoon and evening hours. The initial storms will pose a risk of very large hail and a few tornadoes. As the activity progresses eastward, the risk of damaging winds will increase with a persistent risk of tornadoes. Strong tornadoes will be possible. Storms are expected to get as far east as northwest GA tonight before slowly weakening. ...MO/IL... Satellite imagery shows a well-defined shortwave trough and associated surface low over IA/MO. Ahead of this feature, southerly low-level winds have transported mid 60s dewpoints into central IL, where strong heating is now occurring. This will result in moderate CAPE across the region and encourage rapid thunderstorm development over northeast and east-central MO by mid-afternoon. Steep lapse rates aloft and favorable deep-layer shear will support supercell structures capable of large hail, damaging winds, and a few tornadoes. Storms will track across IL and into central IN this evening. Read more