We are in for a wild week! Warm atmospheric rivers (2 for the west) and cooler air merging from the north. The PNW stays cool while the Sierra and Rockies warm significantly Friday before a cold front enters. Chasing powder can be very tricky timing the colder air, but if you like surfy snow, this storm could be fantastic. Lighter density pow is possible at a few spots in Idaho, and the PNW, or following the colder air in the Rockies as moisture decreases Saturday. On Thursday I sampled 8-9 inches of cold blower at Snowbird as a farewell to the incredible snow quality we have seen for much of the past few months.
The Chase Low Down:
Currently in the Sierra it is raining at lower elevations with temps in the upper 30s to lower 40's at 6200 feet around Tahoe. Temps at 8000 feet are near 30 with 5 inches noted on the Palisades telemetry Friday morning. Winds at 8700 feet are gusting at 132MPH! The snow level climbs Friday to around 7500-8,000 feet before lowering late Friday to Saturday (6500). Rain will mix with snow and likely change to all snow in the Tahoe Basin Friday night with snow levels remaining at 6500 feet (Actual levels may be driven down to 5500 feet in heavy moisture bands). Expect significant snow totals in the Sierra above 8,000 feet with this storm (5-6 feet) and 7-15 inches at lower elevations through Saturday. Snow and rain showers will continue through the weekend before the next Atmospheric Rive approaches Monday. As of 7AM Friday Palisades announced a full closure.
Below: Telemetry from Palisades at the base showing 40 degrees at 4:15 Friday morning. Some cooling occurs late Friday and the weekend driving these temps down to near freezing.
The PNW is going to score the heaviest snow in Oregon from Timberline (15 inches in past 24 hours) south to Bachelor. Further north in Washington moderate amounts will be noted from White Pass, Mission Ridge (5 inches as of Friday AM), Crystal, and extend north to the NE areas of the Cascades. Temps are cooler here than in the Sierra and would be a good choice to chase powder. These areas, especially Oregon might take my top pick for a chase.
On Friday morning, decent totals were noted near Sun Valley with nearly 10 inches at the summit with colder temps. Temps will rise briefly on Friday morning before falling again later in the day with moisture decreasing. Totals in this area could exceed 12-17 inches including what fell Thursday night (A good choice for Friday or perhaps Saturday). Lets, hope they can open terrain prior to the warming (Avalanche concerns). Conditions could be really good on the first chair.
Below: Snow totals through late Friday could be healthy in many areas that benefited from some initial colder temps. Warming is noted for southern Idaho briefly Friday before cooling. The Tetons warm up significantly Friday but cool again for Saturday. (Dense layer stuck in the middle of 2 colder layers). Consider Cat Skiing with Selkirk Powder who currently has very good conditions and limited seats in northern Idaho who will see decent snowfall.
Below: Sun Valley Cam was at 10 inches early Friday morning and it's still snowing.
The Tetons scored some powder Thursday night with temps in the 20's at the base (6-7 overnight at the summits) and good quality. However, warm air is approaching the Tetons so snow quality will be ideal by lift opening, with heavier densities by 10-11 AM. Snow will continue in the Tetons heavy at times Friday prior to a cold front with decreasing snow levels into Saturday and some additional light amounts of higher quality. With an upside layer today, I suspect avalanche danger will rise significantly.
Below: Cold front reaching Wyoming late Friday afternoon after a rapid warm up Friday morning. Utah is going to stay a bit south of the coldest air but will cool Friday night to Saturday morning.
In Utah temps are warmer. The cold front approaches Friday evening but might stall a bit further north towards the Idaho and Wyoming borders. Temps in Utah rise Friday to the lower 30's at 8,000 feet and mid to upper 20's at the summits of the Cottonwoods. Snow will be heavy at times Friday, decreasing somewhat Friday night with colder temps. Areas around Park City, Snowbasin, and even Powder Mountain might see some rain mixed in at the base areas Friday. The cold front seems to get hung up more towards Logan so its possible that Beaver Mountain scores better quality for Saturday. Expect numerous road closures in the Canyons Friday night or early Saturday with 8-15 inches of denser snow at upper elevations, and a soaked snow pack further down Canyon. Winds will add to the mess. Bottom Line: Maybe consider driving north if the Beav scores enough snow Friday/and Friday night, but it will still be dense initially. BCC might be a good option also, and LCC will definitely be closed initially (Has closed for every storm in the past 8 weeks due to high snow load in the avalanche prone areas, however even with 3-6 inch storms remained closed). Who knows if you get lucky, you might be riding 12 plus inches of pure cushion cream with 3-7 inches of lighter density snow on Saturday.
Finally, in Colorado desperately looking to chase powder, I see good indications of high end double digits possible for the Gunnison area mountains (CB) possibly extending into Aspen and certainly to the south in the San Juan Range (Silverton, Purgatory, Wolf Creek). These snow totals might only be found at upper elevations with snow levels rising to 8500 feet or higher at some point late Friday. Heavy surf snow is the name of the game here. There is also indication that even with SW flow, moisture bands will be so intense Friday night that Summit County or even areas of Eagle County nabe double digits up top. My confidence here is less than the central mountains, but it can certainly happen (Watch Breckenridge).
Below: Short term models show deep snow for Colorado, but it might only occur above 9,000 feet. Saturday might be the day to ride some surf.
Overall, the chase for powder might be best in the PNW with some areas of Idaho in the hunt as well (Sun Valley, Selkirk Powder Guides etc.) The Tetons look good for Friday morning (Still cold) and are a wildcard for Saturday (Cooling trend after the warming). I would avoid the Sierra. Look for some chases in the Wasatch, but it's all a matter of how cold it gets with the tail end of moisture. Colorado is pretty surfy but still deep.
Another Atmospheric River hits the west with a similar path, a bit less moisture, but nevertheless a repeat to what we are currently seeing. Some areas of the Sierra may see 7 day water totals in excess of 14 inches! That system moves ashore Sunday night or Monday but there might not be much of a break between them.
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Enjoy the powder everyone!
Powderchaser Steve @powderchasersteve -Instagram
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