BBS: TELESC.NET.BR Assunto: DAY3SVR: Nws Storm Prediction Center Norman Ok De: COD Weather Processor Data: Fri, 13 Mar 2026 19:33:54 +0000 ----------------------------------------------------------- ACUS03 KWNS 131933 SWODY3 SPC AC 131932 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0232 PM CDT Fri Mar 13 2026 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE LOWER MISSISSIPPI RIVER VALLEY TO THE OHIO VALLEY.... ...SUMMARY... A widespread damaging wind event with some tornado threat is likely on late Sunday afternoon through Sunday night from northeast Texas to southwest Lower Michigan. The greatest wind threat appears to be from northeast Arkansas/western Tennessee to southern Indiana during the evening and overnight hours. ...Synopsis... A 100+ knot mid-level jet will lead to rapid amplification as it rounds the base of the mid-level trough across the Central Plains on Sunday. As the associated surface cyclone moves northeastward through the day, strong low-level moisture transport will occur across the warm sector. This will result in weak to potentially moderate instability ahead of the cold front Sunday afternoon. This cold front will accelerate east-southeastward from the Midwest to the Mid-Mississippi Valley during the afternoon and from Ohio to western Georgia/eastern Alabama by Monday morning. ....Ohio Valley... Despite dewpoints only increasing to the mid to upper 50s, a very favorable kinematic environment will be in place with a 70 knot low-level jet and nearly 125 knot mid-level jet by Monday morning. Given this wind field, any instability, combined with the strong frontal forcing, will be sufficient for a powerful QLCS during the evening and overnight hours. This squall line will likely have widespread 60+ mph wind gusts with some stronger 75+ mph wind gusts possible. In addition, very long hodographs with 200+ m2/s2 0-500m SRH will support a threat for line-embedded tornadoes, some of which could be strong. Additionally, the strong shear may also allow for some embedded supercells, also depicted by the 12Z RRFS, which also may lead to a locally greater tornado threat. Pre-frontal development cannot be ruled out, especially from northeast Arkansas to southern Illinois at the nose of the 500mb jet and the northern extent of the richer low-level moisture. This scenario is more uncertain, but could pose a greater tornado threat if it were to materialize. ...Lower Mississippi Valley to the Southeast... The squall line will form during the afternoon, perhaps with some initial supercell/hail threat across Arkansas and northeast Texas and then move northeastward through the overnight period. The strongest low-mid level wind field will remain north of this region, however, greater instability will compensate and should maintain the damaging squall line through the overnight hours. The greatest STP values within the entire risk area are forecast (by the 12Z NAM) between 03Z and 12Z from western Tennessee to central Mississippi and northwest Alabama. Therefore, expect a QLCS tornado threat to accompany the damaging wind threat through the overnight and early morning period. ...FL/AL Coast... Toward the end of the period, richer low-level moisture will begin to move inland across the FL Panhandle into southern Alabama. Within this zone, discrete convection may develop after 08Z. If this were to occur, strong shear would support supercells capable of tornadoes. ..Bentley.. 03/13/2026 $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.28-Linux * Origin: Capitol City Online (1:2320/107) ----------------------------------------------------------- [Voltar]