Hurricane Rosa precedes stormy pattern change for first half of October

Sunday, September 30, 2018

The weather in Steamboat Springs this Sunday will feature continued warm temperatures well above our 65 F average along with breezy southwest winds. Between a vortex of cold air spinning over Hudson Bay, a broad storm off the California Coast and weakening hurricane Rosa off the Baja coast, our pleasant fall weather will turn stormier heading into the first half of October as we first experience warm showers associated with decaying Rosa later Tuesday and then a series of cold fronts that will eventually bring snow to our area.

Some energy ejecting out of the West Coast storm will travel north of our area this Sunday, but bring some afternoon and evening clouds today and Monday, along with the possibility of some light showers. By Tuesday, former hurricane Rosa will be absorbed into the southwest flow ahead of the West Coast storm, and we should see increasing chances for rain as the storm moves near our area by later in the day and through Wednesday morning, with some areas possibly receiving moderate to heavy rainfall for a time.

There may be a small break between the departing former hurricane and a series of cold fronts that will move through our area over the next two weeks starting Wednesday night. Each cold front will bring unsettled weather and increasingly colder air to the region as pieces of cold air in western Canada break away from the Hudson Bay vortex and either mix with incoming Pacific energy or reinvigorate the storm system near the West Coast, or both.

The timing and strength of the cold fronts will certainly be subject to change, but right now there are good precipitation chances for almost every day for the next two weeks. Initially, the West Coast storm is forecast to move inland and pass near our area around next weekend, though additional incoming Pacific energy and cold air from western Canada keep cold and unsettled weather over the western states through the following week as well. For what its worth, it appears the coldest air and the best chance for snowflakes in the Steamboat Springs area will occur early in the work week after next weekend.