
Summary
A low pressure system will drop into the Great Basin and bring showers with high elevation snow to Utah later this weekend through early week. A return to high pressure is likely by late week.
Short Term Forecast
A low pressure system is dropping into California and the western Great Basin right now. This will bring cold air and showers with it over the next several days. You can see this low pressure system clearly dropping into the GB and meandering east through early next week:
Because this system is dropping to our west, the coldest air will moderate somewhat before it progresses overhead. It will also weaken a bit. If this low had dropped over us directly, rather than California, we'd probably see lower snow levels and more widespread precip this weekend. Still, we expect showers to develop by tonight in Utah and continue through Sunday. Snow levels will drop tonight so that the highest elevations could see some flakes by Sunday.
To begin with, the flow will be primarily from the south through Monday morning as the low will be to our west. However, once the low tracks through Utah, the flow will turn northwesterly, which could mean some cool air and orographic showers later on Monday into Tuesday. This is probably the best period for potential snow accumulation in the Wasatch.
Overall, precip between now and Tuesday looks healthy across much of the area:
Enough cold air for some snow in places:
You can see the most likely places for snow are the central and southern Sierra, some mountain ranges of Nevada, and Utah's high elevations. The San Juans and western slope of CO should also see snow, along with the Tetons.
Looking more closely at Utah, the NBM shows solid precip with the highest amounts in Northern Utah:
And snow:
This map shows up to a foot possible in the Uintas, but I think it is underdoing the snow potential in the high elevations of the Wasatch. I'd expect a few inches possible in Wasatch areas above 9000 feet by Tuesday.
Total ensemble plumes are fairly consistent, showing a mean of 0.8" of liquid at Alta by Tuesday:
Most of the snow will be confined to the latter portion of these plumes, so perhaps 0.3-0.5" of liquid during the snow period. That could equate to 2-5" of snow on Monday and Tuesday in the Upper Cottonwoods.
Overall, expect cooler and showery weather for most locales over the next few days. Higher elevations could see anywhere from a dusting to a few inches of new snow to start next week. Uintas could see 6-12" in the highest elevations. That could be enough for a permanent base to begin as we are just starting to reach the period of the year where it's difficult for snow, especially on northern aspects, to melt once it's fallen in any significance.
Extended Forecast
High pressure should take control again later next week and, in general, it looks like we go back to warm and pleasant fall weather for a while thereafter.
Evan | OpenSnow
P.S. Today is the big day for my ski buddy, Ian, and his bride-to-be, Sarah. Congratulations to you both! I wish you many happy, deep powder days ahead together. I can't wait to celebrate with you!