In the short term, your main chase opportunity exists in Colorado. The southern mountains are favored, but looking at all model data, it's possible someone comes up with a surprise on the I-70 corridor. The weekend looks deep for the north Cascades followed by several periods of snow for the Sierra next week.
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Pondering a chase to southern Colorado? Models are fairly bullish for 5-12 inches for many regions north of Durango extending into Wolf Creek Pass. Winds favor the southern San Juan Range initially late Wednesday night (SW) with snow beginning sometime after midnight. The Short Term High-Resolution model pushes similar amounts for Purgatory and Silverton with perhaps slightly less for Wolf Creek. This might be accounting for a slight wind shift Thursday morning from the south (Better for the mountains near Durango) before eventually veering to the NW and pushing snow further north to Telluride and the I-70 corridor Thursday.
The American GFS favors Wolf Creek slightly where the short-term NAM 12 takes a completely different twist with nearly as much snow on the I-70 corridor as the southern mountains. The European Model sides closer with the American Model showing the most snow in the southern mountains (5-10) with much less along I-70.
Below: Looking at the winds you can see the switch to the NW by early afternoon Thursday which will favor the I-70 corridor mountain ranges. If that happens earlier Thursday morning, the last chairs could be decent at some resorts.
Bottom Line: It's likely that 4-8 inches fall overnight Wednesday in most of the southern San Juan Range with another 2-5 possible during early Thursday morning. Purgatory, Silverton, and Wolf Creek might all have similar amounts but not surprised to see the higher totals north of Durango.
Winds veer to the N, NW Thursday morning cranking up snowfall rates for Telluride and the I-70 corridor through Thursday evening. Amounts are variable on the models from 4-9 inches as the best guess by late Thursday. There might be only a few inches on the snow report for the I-70 corridor Thursday morning with the bulk of the snow falling late AM to late PM. Steamboat is a wildcard. The short-term HRR model shows higher amounts perhaps near Ski Cooper and extending towards Berthoud Pass and even Steamboat. Someone near the Front Range might come up with an outlier surprise by late Thursday. This is a tricky forecast so confidence is still on the medium side with higher confidence further south.
Below: Strong low-pressure system taking aim at California next week.
The extended forecast update continues to show a return to snowfall for Whistler later this week. Amounts could be decent. The northern Cascades of Washington fire on Saturday (Mt Baker) with some moderate snow further south from Stevens to Crystal and the Oregon Cascades. The northern Sierra also gets into the action with moderate snow this weekend. The latter part of the weekend into early next week features a stronger low-pressure system taking aim at the Sierra. This might land some impressive snow totals for California that really needs to turn up the hoses next week.
Below: Precipitation Anomalies ending March 13th showing at least 2 inches of water for much of California.