Let me remind everyone where we were only 6 days ago on Friday, February 3rd. We were at the tail end of a heinous inversion period, which finally cracked on that day. Snow cover across the valley was fairly continuous and widespread.
|View from the Natural History Museum of Utah on February 3rd|
If skies were clear during that period, perhaps some valley or bench snow would have survived, at least in shady areas. The sun angle remains fairly low and the amount of energy coming from the sun remains relatively limited for melting snow.
However, we experienced ideal "snow killer" weather conditions with high humidity, rain, and frequent cloud cover. This provides lots of energy for melting snow, especially from condensation and long-wave radiation. Condensation and long-wave radiation are largely equal-opportunity offenders. They don't care what time of day it is or what the aspect is. When conditions are right, they melt snow 24/7 and on all aspects.
So, let's fast forward to today. As I departed for the U from my house in the upper Avenues, I found little snow except in areas where it had been piled deep. The snow level on the Wasatch Range, despite the fact that one spies primarily north aspects from the upper Avenues, was clearly at or above the upper benches.
The forecast highs for today in the Salt Lake Valley are in the low-to-mid 60s. We currently sit at 55ºF at the Salt Lake International Airport. The average high for the day is 41ºF, with a record of 62ºF, although the record for tomorrow is 68ºF (set in 1951), illustrating that astoundingly high temperatures can occur in mid February.
Mountain temperatures are also out on the limb as it is currently 43ºF at the base of Alta and 35ºF at the Alta-Collins site (~9700 feet). I suspect some rain was felt at the base this morning. Further to the north, precipitation has been a bit steadier and drops on the Snowbasin snowstake suggest rain there at 8000 ft where the Boardwalk observing site is reporting a temperature of 39ºF and a dewpoint of 35ºF.