Pretty good weekend storm if you happen to be in the hallowed ground that is Little Cottonwood Canyon. Based on the automated measurements, Alta-Collins got 5 inches of snow on Saturday (with .51" of water), far more than I was expecting (which would have been maybe an inch or two) to get the weekend off right. Then another 14" with 1.54" of water on Sunday, bringing the storm total to 19".
Watching the radar yesterday, it was very apparent that the economics of this storm was going to increase the snowfall wealth divide. Given the northwesterly flow and shallow nature of the storm, echoes tended to be stronger and more persistent over the Salt Lake Valley, lower to middle Big Cottonwood Canyon, and Little Cottonwood Canyon than over the Park City Ridgeline (red line below) or south and east of the Alpine Divide between Little Cottonwood and American Fork Canyon (purple line), as shown in the example below.
Thus, Alta and Snowbird, which flank Mt. Baldy (indicated on the map above) were often getting the goods. Solitude and Brighton, despite not being far away, were often on the edge. Park City and Deer Valley were often skunked. If the Canyons-Daybreak automated snow depth sensors are accurate, they got 6 to 7 inches, far less than Alta and Snowbird.
So, we are currently in a situation where high-north terrain, which has not suffered from losses due to solar radiation or rain, is getting there. Alta-Collins currently has a 32 inch snow depth (this will likely decline some today). My impression from skiing there on Saturday is that it may have rained at that elevation for a time during the storm last Wednesday Night, but there was no loss of snowpack. On the other hand, below 9000 feet and even at upper elevations on the south or west side of the compass, there was little natural snow due to the sun and or the rain from that storm.
More natural snow is needed, but we will be dominated by ridging and a return to mild temperatures until Thursday. Late Thursday and Thursday night, the models are advertising a digging trough to develop over Utah. The GFS brings in precipitation over northern Utah by 0000 UTC 24 November (5 PM Thanksgiving).
And then closes off the low over or just east of Utah through Friday.
The Euro advertises something that is generally similar. The GFS puts out about 0.4" of water and 7" of snow with that system. Most members of the downscaled NAEFS are in the .25 to 1 inch of water range with some higher outliers.
So, another storm where it's wise to keep expectations low and hope we come in on the high end. Don't read into the details at this stage.
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