Very cold arctic air will plunge south beginning in Canada Tuesday and reaching the Rockies Wednesday through Friday. Double digit pow is likley for Alberta, interior BC, and areas of Montana. The Washington Cascades, Coastal BC (Whistler) will all see snowfall early next week albeit lighter amounts. Colorado is going to nab its first measurable snowfall sometime Thursday and Friday. Snow ratios with the colder air may even nab some deeper surprises as liquid to snow amounts may exceed 15:1 at upper elevations (15 inches per 1 inch of moisture). Very cold temps will make this feel like a mid winter storm versus something we would normally see in early October. Valley snowfall is likely in all of these areas.
Its only early October and we are once again talking about deep snow! Cold air will kick off a fast moving system for Whistler and most of the Cascades of Washington on Tuesday (Moderate amounts -N-S). That system moves east over interior BC and Alberta late Tuesday (decent dump). Montana will see decent amounts on Wednesday favoring reorts favored by NE flow (Glacier gets another dump). Our best guess for Glacier is 12-18 inches.
Below: Wind directon on Wednesday. Courtesy of Weathernerds.org
Winds are key to this forecast. Models show direction initially from the north switching to the NE during the highest precipitaiton in Montana before shifting to the NW behind the front. Once the winds shift to the NW areas further west into Bozeman area mountains may be favored. NE winds initially will favor the northern mountains near Glacier. Whitefish is a wildcard. NW flow behind the cold air may provide some deep surprises to areas near Bozeman MT.
Confidence: High for 12-18 inches for Canada (Alberta followed by Interior BC), northern Montana (Glacier National Park). Moderate to high confidence for Bridger Bowl (7-12). Moderate confidence for Big Sky (5-10). High confidence for Red Lodge Mountain ski area (10 Plus).
Utah is a wildcard, with current models showing light amounts late Wednesday or Thursday (Some light snow is possible as low as the Salt Lake Valley). The Tetons will likely see light or moderate snow Wednesday (Lower confidence for deep snow).
\"Hey, wake up Colorado!\" Confidence is high for snowfall to begin in the northern areas (Steamboat) Wednesday night into Thursday. That system moves south Thursday impacting most of the I-70 corridor and perhaps areas south to Monarch. Amounts currently look to be on the moderate side (That could change as we get closer with better model consensus).
Below: Total snowfall thorugh Friday morning highligthing the deepest amounts.
Below: Temps plunging next week with -15C at 9800 feet over much of the Rocky Mountain Region and Canada. This will help to increase snow ratios (Deeper amounts) and bring low valley snow.
We suspect more skinning opportunities this upcoming week! Very windy conditions will preceed the front before decreasing behind the cold air. Early season pow is not a good predictor of an upcoming season! It's a bonus at this point but at the same time may increase the avalanche danger as our season officially begins. ULLR is with us! Enjoy the pow everyone.
Powderchaser Steve