BBS: TELESC.NET.BR Assunto: DAY3SVR: Nws Storm Prediction Center Norman Ok De: COD Weather Processor Data: Mon, 27 Apr 2026 07:32:08 +0000 ----------------------------------------------------------- ACUS03 KWNS 270732 SWODY3 SPC AC 270730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Mon Apr 27 2026 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING ACROSS PARTS OF THE ALLEGHENY PLATEAU INTO MID ATLANTIC AND ACROSS THE NORTHWESTERN THROUGH NORTH CENTRAL GULF COAST... ...SUMMARY... Strong storms could impact parts of the Allegheny Plateau into Mid Atlantic, as well as portions of the northwestern through north central Gulf Coast, Wednesday afternoon and evening, accompanied by at least some risk for severe weather. ...Discussion... Models indicate that mid-level ridging will continue to build inland across the Canadian Rockies/Pacific Northwest through this period, but it appears that attempts at a developing embedded high near the Pacific Northwest coast will become suppressed by a short wave impulse within the westerlies approaching the British Columbia coast. Farther south, a mid-level low merging into a belt of westerlies emanating from the subtropical eastern Pacific may accelerate toward southern California/northern Baja coastal areas, but models vary concerning whether this will accelerate inland prior to 12Z Thursday. A downstream subtropical high, initially centered over southern Mexico, may undergo at least some further southwestward suppression, but it still may maintain considerable influence as far north as the northwestern Gulf coast Wednesday through Wednesday night. At the same time, in higher latitudes, large-scale troughing encompassing much of north central and northeastern North America is forecast to continue slowly digging toward the northern/mid Atlantic Seaboard. A broad embedded cyclonic mid-level circulation may begin to form near/north of the Great Lakes region. The confluent mid-level regime across and east of the Rockies will likely support southeastward development of cool surface ridging across much of the Great Plains and Mississippi Valley, in the wake of a southeastward advancing cold front. Models generally suggest that a modest surface low evolving along this front will migrate from the lower Ohio Valley northeastward through the lower Great Lakes region, with a modest secondary surface low forming along a developing warm front to the east of the Blue Ridge by late Wednesday afternoon into evening. ...Gulf Coast vicinity... It remains uncertain the extent to which pre-frontal convective outflow may impact subsequent destabilization across the north central Gulf Coast region, and perhaps beneath the stronger mid-level ridging into the Texas coastal plain and Rio Grande Valley. However, guidance suggests that a seasonably moist boundary-layer may contribute to moderately large CAPE with sufficient insolation, beneath at least modest west-northwesterly mid-level flow. This environment might become conducive to at least widely scattered storms with potential to produce severe hail and wind. It is still possible that categorical and severe probabilties could be increased further in later outlooks for this period. ...Allegheny Plateau into Mid Atlantic... The influence of potentially widespread remnant early period convective precipitation on subsequent destabilization through the day Wednesday remain unclear. However, as a fairly significant short wave perturbation overspreads the region late Wednesday afternoon and evening, the cold front approaching the Allegheny Mountains, surface troughing and the developing low/warm front to the east of the Blue Ridge could become the focus for strong to severe thunderstorm with sufficient destabilization in the presence of strong deep-layer shear. It is still possible that categorical and severe probabilities could be increased further in later outlooks for this period. ..Kerr.. 04/27/2026 $$ = = = 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]