Thursday, September 17, 2020
The Steamboat Springs area has seen a high temperature so far of 78 F under mostly sunny and hazy skies this Thursday afternoon. Winds will increase ahead of a grazing storm mid-weekend that will likely produce more wind than rain, with a leftover part of that storm eventually moving over our area during the midweek period and bringing a slightly better chance of showers. We should see high temperatures decreasing from the five to ten degrees above our average of 71 F on Friday and Saturday to the more seasonable mid to lower seventies from Sunday through the following work week.
A storm currently just off the Pacific Northwest coast is forecast to move inland this weekend, deflecting the ridge of high pressure that is currently over the Intermountain West. The smoke plume forecast over the next day shows the smoke currently over our area from the Middle Fork fire and fires over the Uinta Mountains in Utah abating by tomorrow afternoon as winds turn to be from the current northwest to the west ahead of a weak cool front for Saturday.
However, winds are forecast to become breezy ahead of and along the front, which is expected across our region later Saturday, and will not be good news for the wildfires. There is some moisture associated with the storm, but it looks high-based and brief, bringing a meager chance for showers Saturday afternoon and evening.
Winds decrease on Sunday and turn to be from the southwest on Monday ahead of a piece of the weekend storm that was left behind off the coast of California. This piece will be slowly carried over our area through midweek, and though weather forecast models are not in complete agreement on the strength of the storm as it passes over our area, it does appear we will see a weak cool front on Wednesday.
Moisture may be increasing over our area as soon as later Monday, with a slightly better chance of showers on Tuesday and Wednesday as compared to the mid-weekend storm, though chances are still not high. The strength of the wave will determine the amount of cooling we see with the front and whether the winds shift to be more from the northwest behind the front.
Incidentally, the autumnal equinox will occur Tuesday morning at 7:30 am MDT when the sun passes over the equator, so while days will become shorter until the winter solstice, the daily rate at which we lose daylight will start decreasing.
There is considerable uncertainty heading into next weekend as the European ECMWF has a faster and shallower Pacific wave grazing our area and staying mostly dry, while the American GFS has a slower but stronger and wetter storm encroaching over our area by the end of the weekend. Stay tuned to my next regularly scheduled weather narrative on Sunday afternoon to see what we have in store for the last weekend in September.