From late yesterday afternoon until 7 AM this morning, Alta-Collins has observed 1.09" of water equivalent and Snowbasin Middle Bowl 1.15". Ben Lomond Peak is around 1.4".
Temperatures at Alta-Collins (9662 ft) peaked at 32ºF from 11PM to midnight, afterwhich they lowered gradually and then more abruptly with the passage of the cold front early this morning.
At the base of Alta (8560 ft), and at Snowbasin Middle Bowl (7402 ft) it reached 37º. Thus, rain may have mixed in with snow as high as the lower slopes of Alta and Snowbird and mid mountain Snowbasin during the warmest part of the storm around midnight. Temperatures have since fallen and the recent passage of the cold front has lowered snow levels to the valley floor.
At upper elevations, the 1.09" of water at Alta-Collins yielded a total of 6" of snow, yielding a water content of 18%. Serious Sierra Cement. However, the snow falling this morning and today should be drier.
The radar loop is one that makes me really happy because it means snow for all elevations today.
There's nothing like a combination of atmospheric river moisture and frontal dynamics to give a solid band of precipitation. Better yet that it will be moving slowly through northern Utah. Thus, I'll stick with my storm total precipitation (1.5-2.25") and snowfall (12-20") forecast for Alta through 5 PM, but will note that the cards are stacked for totals in the upper half of those ranges.
I love it when a storm comes together!