President's weekend is upon us. Aspects of the forecast are easy. There will be tourists, traffic, and crowds in the Cottonwoods. How about powder?
The latest GFS forecast brings a cold front into northern Utah Saturday night. We should get a period of widespread snowfall in the mountains and the valleys as the front moves through.
If the timing of the GFS forecasts is accurate, snowfall rates in the Cottonwood Canyons will be highest late Saturday and Sunday morning.
This looks to be a right-side-up storm, with decreasing snow water contents over time, as often occurs with frontal passages. Our snow water content algorithms, when directly applied to the GFS output, suggest an initial snow water content of ~8% at Alta, falling to ~4% later in the storm.
When applied to the liquid precipitation forecast from the GFS, this yields an accumulation of about 8" of snow at Alta. However, the GFS does not fully account for local orographic effects. Thus, going for something ~10–14" at Alta by Sunday afternoon is probably more appropriate.
Update 2:50 PM: To clarify, late Saturday should be late Saturday night - JS