BBS: TELESC.NET.BR Assunto: HVYSNOW: Probabilistic Heavy Snow And Icing Discussion De: COD Weather Processor Data: Sun, 29 Mar 2026 07:01:45 +0000 ----------------------------------------------------------- FOUS11 KWBC 290701 QPFHSD Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 301 AM EDT Sun Mar 29 2026 Valid 12Z Sun Mar 29 2026 - 12Z Wed Apr 01 2026 ...Pacific Northwest/Northern Rockies... Days 1-2... A sharp positively-tilted upper trough just west of Vancouver this morning will continue to push eastward as its cold front moves through WA/OR today. Despite some infusion of mid-latitude Pacific moisture, the system will weaken a bit and remain progressive, limiting QPF amounts. Lower snow levels around 2500-4000ft in the Cascades this morning will lower behind the cold front to 1500-3000ft. This will bring some snow to the passes and probabilities for at least 6 inches are at least 50% above about 3000-3500ft or so for the Washington Cascades. Farther east, moisture will stream into the northern Rockies late this afternoon/tonight and eventually into Wyoming late Monday into Tuesday, ending from west/northwest to east/southeast as the cold front moves to the east quicker than it sinks to the south. Amounts will again be generally light, but northwestern Montana may see totals in excess of a foot around Glacier NP (50-80% chance). In general, probabilities of at least 6 inches of snow are at least 50% above about 5000ft in ID/MT but above 9000-10,000ft in WY. The Absarokas in southern MT into northwest WY may also see slightly higher totals due to some local surface convergence. Front end of the precip shield advancing across the Northern Plains could support some light icing (generally a few hundredths of an inch) over northern ND early Monday then into northeastern MN and perhaps the U.P. of Michigan as the system redevelops over the Plains/Corn Belt. ...Northern New England... Day 3... The system over the Great Lakes on Monday (above) will move into the Northeast on Tuesday. Marginally cold temperatures will be limited to northern NY/VT/NH and much of interior Maine as precipitation advances into the region Tuesday morning along and ahead of a surface warm front. With the main area of low pressure quite far to the west early Tuesday (WI or into Lower MI), cold air may hang on longer in sheltered areas over northern New England which would support some light snow to start but then more likely a period of freezing rain. AI guidance suggests colder temperatures than the dynamical models Tuesday night into Wednesday morning, hinting at at least non-trivial amounts of freezing rain (though the better signal lies across Canada near/northeast of Ottawa). For now, kept amounts to around a tenth of an inch but with the potential to trend higher in the next couple of days. WPC probabilities for at least 0.10" icing are >30% over northwestern Maine. ...Sierra Nevada to the CO Rockies... Day 3... Combination of the tail-end of the Pacific Northwest/northern Rockies system today/Monday and an incoming weak shortwave out of the Pacific Tuesday afternoon will bring some light to perhaps modest snow to the Sierra and CO Rockies and dotted across the Great Basin in between. Snow levels will be high -- 8000-9000ft -- with WPC probabilities for at least 6 inches of snow between about 40-80% above 9000-10,000ft. The probability of significant icing across the CONUS for days 1-3 is less than 10%. Fracasso $$ = = = 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]