Rain likely by midweek
Sunday, September 26, 2021
The Steamboat Springs area is enjoying another quintessential Colorado fall day with temperatures in the seventies and nary a cloud in sight this Sunday noon. The spectacular weather continues Monday before the weather becomes unsettled by later Tuesday and likely wet by Wednesday.
Two weather features will affect our weather by Tuesday afternoon; an eddy of low pressure currently in central Arizona and a strong storm currently in the Gulf of Alaska. But we’ll get another couple of gorgeous fall days today and Monday before the Gulf of Alaska storm is forecast to cross the Pacific Northwest coast Monday night.
The Arizona eddy will be forced to the northeast and toward our area on Tuesday as it is incorporated into the southwest flow ahead of the Pacific Northwest storm. There may be some clouds around on Monday at times in advance of the eddy, with cloudiness increasing on Tuesday ahead of increasing shower chances by Tuesday afternoon or evening.
Meanwhile, the Pacific Northwest storm is forecast to enter the Great Basin on Tuesday and send a cold front through our area on Wednesday. Between the subtropical moisture carried over our area by the eddy and the cold front with the approaching storm, expect high chances for widespread showers by Tuesday night, with lesser but still significant chances continuing through Wednesday.
While high temperatures today and tomorrow will be in the seventies, five to ten degrees above our average of 67 F, they will cool a bit Tuesday under the clouds, and drop to five to ten degrees below average on a showery Wednesday.
Snow levels behind the cold front should drop to between 9000′ and 10,000′, and though the coldest air comes late Wednesday after the best moisture has left the area, there should be up to an inch or two of snow on the upper third of Mt. Werner by Thursday morning.
The storm is expected to split over the Great Basin by late Wednesday, with a fair bit of uncertainty with respect to how much energy is partitioned between the eventual northern and southern parts of the storm, but right now another eddy that may eventually influence our weather is forecast to be left behind in the southern Great Basin or Desert Southwest. We may see some showers on Thursday afternoon that persist through the weekend, according the European ECMWF, or rapidly diminish, according to the American GFS, or some sort of compromise. Stay tuned to my next regularly scheduled weather narrative on Thursday afternoon where the weather for next weekend will be in better focus.
