Friday, January 31, 2014
Two waves in the Pacific branch of the polar jet stream stayed further south than I expected yesterday, with the first wave overnight yesterday giving big snows to Winter Park and Loveland, and the second wave during the day yesterday and overnight last night giving big snows to the rest of the I70 corridor and the Aspen areas. Clearly disappointing for us, and in hindsight, I should have placed greater emphasis on both the fact that Steamboat tends not to do well with predominantly westerly flow and models consistently had the best energy just to our south.
Furthermore, the wave for today also will affect the areas south of us the most so only light snow is expected this afternoon and tonight. However, a another arctic wave rotating around the persistent Hudson Bay vortex will begin cooling temperatures tonight and turn the flow to the northwest keeping light snowfall going through most of Saturday. This snow should of much lighter density as the heavy riming that occurred in yesterdays storm will be absent. I would expect 1-4” both on the Saturday and Sunday morning report, with most if not all of the snow in the Sunday morning report occurring before midnight Saturday.
Sunday should be a nice day with a cold start and the sun will make an appearance, especially in the afternoon. The low that I originally thought would stay south of us will affect our area on Monday with light snowfall as the warm and moist southwesterly flow ahead of the storm overruns the cold arctic airmass left by Saturday’s wave.
Additionally, another arctic wave rotating around the Hudson Bay vortex will force the California low westward and turn our flow to the northwest Tuesday evening, increasing very light and dry snowfall. Wind speeds stay very low as they decrease behind the departing low to our south, and that will limit accumulations Tuesday and Tuesday night. At this point, I would guess 1-4” on both Tuesday and Wednesday morning, with light snow showers and minimal accumulations continuing through day Wednesday.
Another small break on Thursday before the Siberian vortex splits and cross polar flow brings another round of bitterly cold air across the North Pole and into western Canada. There is a fair bit of uncertainty with respect to the interaction of this arctic airmass and the polar jet carrying mild and moist Pacific air, but an active pattern, especially for the west coast is likely for next weekend.