BBS: TELESC.NET.BR Assunto: DAY2SVR: Nws Storm Prediction Center Norman Ok De: COD Weather Processor Data: Wed, 25 Mar 2026 05:58:16 +0000 ----------------------------------------------------------- ACUS02 KWNS 250558 SWODY2 SPC AC 250556 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Wed Mar 25 2026 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE MIDWEST AND GREAT LAKES... ...SUMMARY... Scattered strong to severe thunderstorms are expected late Thursday afternoon and evening across parts of the Midwest and Ohio River Valley. Very large hail, a few tornadoes, and severe winds will be possible. ...Synopsis... Latest GOES water-vapor imagery depicts an upper wave encroaching upon the Pacific Northwest/northern Rockies and southern British Columbia as it rounds the apex of a stout upper ridge situated over the West. This feature is expected to migrate eastward over the next 48 hours, reaching the Great Lakes region by late Thursday. Early-morning surface observations reveal the early stages of lee cyclogenesis across the northern High Plains with a long fetch of southerly flow from the TX Gulf Coast into the Plains. While moisture return is currently fairly weak, a plume of upper 50s to low 60s dewpoints will spread northeastward into the Midwest/OH Valley by Thursday afternoon ahead of a southeastward moving cold front. Strong forcing along the front within a destabilizing air mass, combined with increasing mid-level flow attendant to the upper wave, will promote scattered strong to severe thunderstorms across portions of the Midwest and OH Valley Thursday afternoon and evening. ...Midwest/Great Lakes... Thunderstorm development is expected by late afternoon across the southern Lake Michigan region as the cold front begins to impinge on a plume of returning moisture. Stout capping at the base of an EML will likely limit initial storm coverage, and elongated hodographs (featuring 40-50 knot effective bulk shear values) will promote organization of discrete/semi-discrete supercells for at least an hour or two. Given the very favorable convective environment (characterized by SCP values upwards of 8-12), large to very large (2-3 inches in diameter) hail appears possible. However, it remains unclear how long storm modes will remain discrete with latest HRRR, RRFS, and MPAS solutions all suggesting relatively quick upscale growth along the front by early evening. These solutions appear reasonable given strong frontal ascent and deep-layer flow predominantly along the boundary. This may modulate the duration/coverage of the significant hail threat, and would favor a scattered severe wind threat downstream into IN and OH. Regardless, 200-400 m2/s2 effective SRH immediately ahead of the front will support some threat for tornadoes, including the potential for a significant tornado if supercells can be maintained just ahead of the front. Additionally, the consensus among HREF/REFS solutions is a northward shift in the primary severe risk corridor towards northern IL/IN, southern lower MI, and northwest OH. 15% hail and wind probabilities were adjusted accordingly. More isolated strong/severe storms appear possible with southwestward extent along the front into central MO, but confidence in storm coverage west of the MS River is limited due to displacement from the richer moisture and stronger upper-level ascent. ..Moore.. 03/25/2026 $$ = = = 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]