Some high-altitude locations such as the top of Snowbird have already seen their first snow, but on Saturday we may see a bit more wide spread snowfall.
The latest GFS shows a bonafide cold trough moving across northern Utah at 1200 UTC 4 October (0600 MDT Saturday) with an accompanying cold front and precipitation system.
Our GFS-derived machine-learened forecast product for upper Little Cottonwood shows temperatures on Mt. Baldy (11,000 ft) and at Collins (9,700 ft) plummeting Friday night and Saturday along with wet-bulb zero levels dropping to near 8000 feet by noon Saturday. If that verifies, that would probably put the snow level Saturday afternoon around 7500 feet.
For Collins' 9700 foot elevation, the GFS is producing a total of about 0.8" of water. The storm begins with rain at that elevation Friday afternoon, but eventually changes to snow Friday night. Total snowfall of just over 4".
The Utah Snow Ensemble is a bit more jacked. 75% of the 82 members produce 5.6" of snow by 12Z 5 Oct (6 AM Sunday).
Our snowfall estimates do not consider melt on the ground and the vertical resolution of the Utah snow ensemble is such that it's snow-level forecasts are somewhat uncertain. That said, I expect to see the white stuff Saturday at elevations above about 8000 feet (possibly lower) with the first wide-spread accumulations at upper elevations. My best guess right now is 3-6" for Alta-Collins.
Main chute on Saturday lets gooooo
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