A storm system will bring fairly significant snowfall to the mountains of Northern Utah late Tuesday into Wednesday. Snow showers will continue at times into this weekend. Next week, a ridge of high pressure will build and we will see clearing and warming conditions.
Short Term Forecast
Is it just me, or does it feels like we basically went straight from summer to winter? I have spent a lot of time hiking and biking up in the foliage in the mountains over the past few weeks. Still, two weeks ago I was hiking in a tank top, worried about a sunburn, now I'm bundling up and prepping my touring gear.
The transition to winter gets even more serious tonight. We have a serious winter snow storm on our doorstep. Over the past 48 hours or so, I've gradually watched everything come together in the models. The system has good organization, plenty of moisture, and solid amount of cold air and instability. This is a recipe for a solid Wasatch snow storm. Snow should begin this evening from north to south and continue overnight into tomorrow morning. Latest NAM-WRF model output shows the following amounts:
This is what I call an equal opportunity storm. All mountains in the state should see snowfall. You can see areas of pink color all the way down to Brian Head. Eagle Point, the Uintas, the La Sals, and all of the Wasatch are in the pink. Generally, these areas will see 6" or more of snow. There are a few areas of light blue and white inside the pink areas that signify over a foot of snowfall. Some of these areas include Snowbasin down to Emigration Canyon and Mt Timpanogos. The Cottonwoods should also do well. The 12km NAM is up significantly since yesterday morning:
Looks like up to a foot is easily a possibility. This model also sometimes underestimates snowfall in this type of pattern as well, it's higher resolution sister (3km NAM) is showing 16". Overall, I think 6-12" is likely above 7,000ft in the Wasatch. 12"+ will be possible in a few favored locations. Maybe not a huge snowstorm mid-winter, but this is definitely notable for October 10th.
Snow showers will continue into Thursday with a follow-up disturbance. Additional chances for a few snow showers this weekend. Then warming and ridging next week.
High pressure ridge will take control next week. It looks like this could stick around for awhile. This is basically a worst case scenario for backcountry stability. We are going to have plenty of snow on the mountains. With the low sun angle, it's unlikely that we'll be able to fully melt off the northerly aspects even with an extended period of warm weather. We could see some weak base layers. This is not a concern for those who ski in resorts as avalanche mitigation is done in-bounds -- only for backcountry skiers. Let's hope that snow returns sooner rather than later!
Evan | OpenSnow