Clouds and breezes increase today ahead of a clipper system that will drop in out of the north this evening into tonight and continue through Friday morning. Not a strong system by any stretch of the imagination, but will be enough to bring light snowfall amounts to the mountains of Northern Utah as well as clear out valley inversions as we head into the weekend. 

If you've been reading the forecast the past two days, not much has changed. Snow should begin in Northern Utah mountains by late this evening and continue overnight into Friday morning before clearing out by Friday afternoon. Liquid amounts with this system remain somewhat meager -- latest WPC blend showing light amounts for the mountains:

Our downscaled GEFS plumes this morning showed a general range of 0.3-0.6" for the Cottonwoods with a mean just under 0.5" of liquid. Other areas of the Wasatch were generally in the 0.2-0.4" range. When we use an average snow ratio of 12:1, that means that roughly 2-6" of snowfall is expected. For some that might mean dust on crust tomorrow, while for others it could be a modest powder day. It's definitely worth keeping your attention on webcams, radar, and snow reports tomorrow morning. This has potential to be a low-hype, sleeper powder day if we get lucky with higher-end amounts. 

The other benefit of this system is it should be plenty strong enough to scour out the valley inversions, so we should have cleaner air for at least a couple of days this weekend behind the system. Highly possible that inversions can return next week, but for now we should get a break. 

Quiet this weekend into early next week. Models do show another system dropping into the Northern Rockies around Tuesday of next week. It is possible we could get clipped again with some clouds, light snow showers, and cooler temps. However, it's also possible this system stays to our north and east. 

All eyes remain on a potential pattern change at the end of the month into early February. We are just now starting to get within 10 days of this pattern change. Every day that we get closer and models continue to show it and not push it back is an incremental gain in confidence. The PNA index, which is an indicator of the overall North American pattern, is expected to go strongly negative late next week:

This is yet another indication that models are picking up on the idea of switch in the large-scale patterns to one in which the western U.S. is favored for storms. Too early for any details still, but we will continue to watch this and should start to see individual storms take shape as we get closer. 

Evan | OpenSnow