BBS: TELESC.NET.BR Assunto: HVYSNOW: Probabilistic Heavy Snow And Icing Discussion De: COD Weather Processor Data: Wed, 25 Mar 2026 07:07:18 +0000 ----------------------------------------------------------- FOUS11 KWBC 250707 QPFHSD Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 307 AM EDT Wed Mar 25 2026 Valid 12Z Wed Mar 25 2026 - 12Z Sat Mar 28 2026 ...Washington Cascades to Northern Rockies... Days 1-2... An approaching shortwave trough and an associated cold front will track through the Pacific Northwest with upsloping winds and sufficient Pacific moisture to produce mountain snow over the Olympics and Cascades. Height falls and CAA in wake of a cold frontal passage will cause snow levels to drop to as low as 2,500ft this morning. Precipitation rates will gradually decrease throughout the day, but persistent upslope flow will keep snow in the forecast in the Cascades and Olympics as low as 2,500ft in elevation through early Thursday morning. WPC probabilities depict moderate chances (40-60%) for snowfall totals >4" at Snoqualmie Pass and >8" at Stevens Pass. Most of the heaviest snowfall totals (>8") will be confined to more remote elevations above 4,000ft. Conditions at pass level should improve throughout the day Thursday with snow concluding and higher late-March sun angles helping to melt snow on paved surfaces. Snow snow will spill east into the Northern Rockies as well, but any accumulations will generally reside in the more remote elevations (Glacier NPS the lone exception). Most snowfall amounts will generally range between a coating to 3", but some locations along the Lewis Range and Glacier NPS could see some localized snowfall totals surpass 6" before snow concludes by Thursday afternoon. ...Upper Midwest to Northern Maine... Days 2-3... A series of sheared 500mb vort maxima will generate light wintry precipitation in portions of the Upper Midwest and northern Maine the second half of the week. Focusing on northern Maine first, a clipper system racing through southeast Canada Wednesday night will escort a plume of moisture aloft within a corridor of 850-700mb WAA over New England. Most of New England's boundary layer temperatures will be too mild to support snow, with the lone exception being far northern Maine. Snow will develop over northern Maine late Wednesday night and linger through Thursday morning, before finally ending Thursday afternoon. Snow fall rates will not be overly heavy and the bulk of the snowfall will occur during the day, which will limit snowfall totals thanks to the increasing strength of the late March sun angle. Still, the border of Quebec and northern Maine could still pick up some localized snowfall totals >4" (WPC 24-hour probabilities show low-to-moderate chances (20-40%). Some light snow may linger into Friday over the northern Appalachians and northern Maine Friday morning as the next clipper system passes well to the south. At the same time as snow is unfolding across northern Maine on Thursday morning, the next 500mb vort max is racing through the Upper Midwest with a weak surface low tracking from eastern NE into the heart of the MS Valley. Minor freezing rain and snow accumulations will occur on the northern flank of the storm track with WPC probabilities showing moderate-to-high chances (50-80%) for >0.01" of ice accumulation from as far west as eastern ND to as far east of the tip of Michigan's Mitt. It is worth noting WPC probabilities for >0.1" of ice are <10%, so most ice accumulations will be minor and struggle to accumulate on paved surfaces, especially during the day on Thursday. The Huron Mountains are the lone area where localized snowfall totals could top 2", but otherwise the marginal boundary layer temperatures will make snowfall more conversational rather than impactful on Thursday morning. The chances for significant icing across the CONUS is less than 10%. Mullinax $$ = = = 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]