I awoke this morning to a beautiful mountain wave cloud that was draped over the Traverse Range at the southern end of the Salt Lake Valley.
Mountain waves form during flow across topographic obstacles. The Traverse Range has a maximum elevation a bit over 6500 feet, and a deep gap where it is bisected by the Jordan River, but is plenty high enough to generate such waves despite being small compared to the surrounding Wasatch and Oquirrh Mountains. One often sees mountain wave clouds over the Traverse Range (and typically Lone Peak as well) in advance of approaching storms, so whenever I see one, I take a peak at the latest computer models.
Indeed we have a trough approaching northern Utah this morning and expected to move across the area tonight, bringing precipitation to all elevations.
Mountain snow and valley rain will begin late today, with precipitation changing to snow at all elevations overnight. For the mountains, this is looking like a pretty good storm tonight. I'm thinking 6-12" in the upper Cottonwoods by 8 am tomorrow morning, with another 2-4" after that time tomorrow. This is a bit more optimistic than the National Weather Service, which is unusual given my conservative forecast streak (they are calling for a 6-12" storm total). Given that I'm still half asleep, perhaps you should keep your expectations low so you are pleasantly surprised tomorrow. Low expectation are, afterall, the key to great powder days.
Normally I would call this a nice Goldilocks storm, but given the snowpack problems we've been dealing with, it's bound to cause further stress and problems. Be careful out there.