BBS: TELESC.NET.BR Assunto: DAY1SVR: Day 1 Convective Outlook De: COD Weather Processor Data: Thu, 26 Mar 2026 12:48:23 +0000 ----------------------------------------------------------- ACUS01 KWNS 261248 SWODY1 SPC AC 261246 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 AM CDT Thu Mar 26 2026 Valid 261300Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms are expected this afternoon and evening across parts of the Midwest and Ohio Valley. Large to very large hail, a few tornadoes, and severe/damaging winds all appear likely. ...Mid Mississippi Valley into the Midwest/Ohio Valley... Upper ridging will remain suppressed over the Southwest and southern Plains today as rather strong westerly mid/upper-level jets overspread the Upper Midwest/Great Lakes. A weak mid-level shortwave trough that has encouraged occasional lighting flashes with convection across the NE Panhandle earlier this morning will approach the mid MS Valley/Midwest by late this afternoon. A cold front is forecast to move southward through the day across IL/IN/southern Lower MI/OH as a weak surface reflection develops eastward into central PA through this evening. A partially modified/shallow Gulf airmass will stream northward ahead of this front, with surface dewpoints generally expected to remain in the mid 50s to no more than low 60s. Current expectations are for thunderstorms to quickly develop along the length of the front from central IL eastward into IN, southern Lower MI, and northern OH by 19-22Z as diurnal heating erodes lingering convective inhibition. Even though low-level moisture should remain fairly shallow/limited ahead of the front, a narrow corridor of 1000-1500 J/kg of MLCAPE (locally stronger possible) is forecast to be present by mid to late afternoon given sufficient daytime heating and steepening mid-level lapse rates. Strong flow of 50-60+ kt in the 700-500 mb layer and related deep-layer shear of similar magnitude will support organized updrafts and supercells with this initial development. Large to very large hail (2+ inches in diameter possible) should occur as long as a supercell mode can be maintained. A fairly quick transition to more linear structures appears likely given the frontal forcing, with an increasing threat for scattered to numerous severe/damaging winds as one or more clusters spreads east-southeastward across much of the OH Valley into western/central PA through the late afternoon and evening. Given the forecast strength of the low to mid-level flow, isolated gusts of 75+ mph may occur. There is a threat for a few tornadoes as well with both supercells and embedded mesocirculations within the linear clusters, although a well-mixed boundary layer should increase LCLs this afternoon as surface temperatures generally warm into the 70s and 80s. Some guidance suggests a locally greater threat for tornadoes (perhaps a couple strong) may exist across parts of northern/central IN/OH with any supercells that can be maintained along/ahead of the cold front, as low-level shear should be greater across these areas in association with a 35-50 kt west-southwesterly low-level jet. However, confidence in this scenario occurring was too low to include higher tornado probabilities with this update. Farther west across the mid MS Valley (MO into eastern KS), there is lower confidence in warm sector thunderstorm development this afternoon and evening due to the presence of a stronger cap. However, elevated convection may occur along/behind the cold front this evening, with strong deep-layer shear and sufficient MUCAPE conditionally supporting supercells with mainly a threat for large hail. Have made only minor changes to the Slight Risk across this area based on latest guidance trends. ..Gleason/Kerr.. 03/26/2026 $$ = = = 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]