Wednesday, February 3, 2021
The first in a series of advertised storms arrived this afternoon, courtesy of a snow squall, and Steamboat Springs is currently seeing light to moderate snow late this Thursday afternoon. Snows are possible for every day during the upcoming week, with the heaviest and most persistent snow forecast for Friday and to a lesser extent Friday night.
The main part of the storm today is still back in Utah, so snow will continue through the night. The storm is about 6 hours slower than I originally thought in the last weather narrative, so the expected snowfall for the Thursday morning report is now in the 4-8” range.
As the storm departs our area on Thursday, we will be left with persistent northwest flow between a ridge of high pressure over the Gulf of Alaska and a deep and cold area of low pressure over the East and the Midwest. The Park mountain range just east of Steamboat Springs is favored under this regime, which is forecast to last through upcoming week, so expect some snowfall for most of the days as the air is forced up the slope of the mountains and orographic, or terrain-driven, snowfall ensues.
Waves of energy and moisture will periodically pass overhead and increase snowfall rates, with one potent wave passing overhead on Friday and Friday night. We may see several more inches during the day Thursday before snows pick up Thursday night followed by periods of moderate to heavy snow on Friday and Friday night, likely most intense on Friday afternoon.
If weather model forecasts hold, we could see 3-6” of snow on the Friday morning report and 8-16” by Saturday morning, with more than half of that falling during the day Friday. Snow will continue at lesser rates Saturday morning before tapering off in the afternoon and overnight.
Though we will see a break on Sunday between waves, it is not clear if snows will stop or just become very light. And another couple of waves may move overhead or nearby on Monday and possibly Wednesday, though that may change as these impulses are hard to time since they are embedded in fast flow from the sparsely observed Pacific.
The setup for this upcoming week is ideal for our area, though our eventual snowfall will be determined by how long we can stay in the moist northwest flow. Though weather forecast models agree on the wave for around Monday, they disagree on whether the ridge of high pressure over the Gulf of Alaska moves toward our area by midweek and deflects the storm track to our northeast, like the European ECMWF, or the ridge stays put and allows another wave to pass overhead in northwest flow, like the American GFS.
The storm track will be determined by the outcome of the battle between the warm air under the ridge of high pressure in the Gulf of Alaska and the very cold air over the Midwest and East. Eventually, both weather models do have the ridge moving inland late in the work week or the following weekend, though it is accompanied by fast westerly flow from the Pacific moving through the ridge, and this weather pattern can also be productive for the Rockies, especially if low-level cold air can hang around.
My next scheduled weather narrative is on Sunday afternoon, and I’ll have some hopefully impressive storm totals to talk about as well as discuss the additional snowfall expected during the following work week.