The real surprise, however, was in the mountains. The Little Cottonwood snowmaking machine was really cranking last night with Alta-Collins picking up 11 inches of cold smoke. That appears to be quite a bit more than fell elsewhere in the Wasatch, as well as that predicted by the models and by operational forecasts. The National Weather Service Little Cottonwood forecast issued yesterday afternoon called for a 20% chance of a trace and an 80% chance of 1-3".
We still have some work to do, especially regarding what I like to call the "post-frontal crap shoot." It is during these periods of northwesterly flow, when snowfall is produced by shallow convective clouds that are highly sensitive to the depth and strength of instability and moisture, as well as with flow interaction with the mountains and sometimes the lake, that we struggle the most. Last night provides a good example.