Cold and snowy week ahead
Sunday, March 19, 2023
Chilly temperatures in the low teens and sunny skies are over the Steamboat Springs area at all elevations this Sunday mid-morning. Even though the first day of spring is tomorrow, the weather has other ideas as a series of wet and increasingly cold Pacific systems bring chances for snow for each day of the work week that will continue into next weekend.
Our gorgeous three day stretch of mid-winter-feeling weather this weekend ends in a dramatic fashion for the first day of astronomical spring, which occurs at 3:24 pm MDT on Monday during the vernal equinox, when the sun crosses over the equator for its northern hemisphere summer stay.
A very active weather pattern currently spans the entire Pacific ocean, with chunks of very cold air continually breaking away from Siberia and eventually mixing with relatively narrow but very wet atmospheric rivers from the subtropics.
A cold storm currently in the Gulf of Alaska has mixed with an atmospheric river near Hawaii, colloquially known as the Pineapple Express, and a wave of energy ejecting out of the storm is bringing another round of heavy precipitation to the Sierras. The wave will cross the Great Basin tonight, and we should see increasing clouds later today before precipitation breaks out during the day Monday over our area.
Winds at mountain-top level will shift to be from the current southwest direction to the west later Monday and eventually our favorable northwest direction overnight. While it is always tricky predicting snowfall in the generally unfavorable southwest flow thanks to winds downsloping off the Flat Tops and drying the atmosphere, 1-4” of snowfall is possible in the afternoon, with another 3-6” likely overnight at mid-mountain at the Steamboat Ski Resort.
Snowfall should end for a short time during the day Tuesday behind the wave, and there may even be some sun ahead of the next more significant precipitation event on Wednesday. Another cold storm with Siberian origins currently east of Japan is forecast to cross the Dateline on Monday and force the Gulf of Alaska storm bodily eastward and across the central California coast on Tuesday.
More of the Pineapple Express is forecast to be incorporated into the storm which will eventually span the entire West by Thursday after energy either ejects out ahead of it or rotates around it. Right now, the most intense precipitation should be between Tuesday night and Wednesday afternoon, first in winds from the southwest and then the west if the center of the storm reforms over Wyoming Wednesday night as currently forecast.
I would expect 1-4” of snowfall at mid-mountain by the Wednesday morning report, with another 4-8” for the Thursday morning report. Cool and snow-showery weather looks to continue for the rest of the work week as that Japan storm eventually reaches the Pacific Northwest coast on Thursday and we see favorable cool, somewhat moist and unstable northwest flow between the incoming and departing storms.
It currently looks like that Japan storm will eventually move near our area to start the following weekend for more snow chances, though there is a lot of weather to get through before there is some certainty to that forecast. So be sure to check back Thursday afternoon for my next regularly scheduled weather narrative where I will focus on that next weekend storm.
Beautiful but cool weekend ahead
Thursday, March 16, 2023
After seven inches of new snow was reported at mid-mountain at the Steamboat Ski Resort and a foot up top, mostly sunny skies with cool temperatures in the upper twenties are over the town of Steamboat Springs this Thursday mid-afternoon with low teens near the top of the hill. A very pleasant weekend with cool temperatures and continued mostly sunny skies will precede what is currently looking like another significant storm for the following work week.
The northern branch of our departing storm is currently located in the Dakotas while an area of low pressure associated with the southern branch spans from southern California to the Texas panhandle. Counter-clockwise flow around the northern branch has allowed winds from the north to carry additional cold air from the central Canadian Plains over our area, with the high temperature for today in town staying over ten degrees below our average of 42 F.
Low temperatures this weekend will be even further below our average low of 18 F, especially for Friday morning as subzero temperatures twenty to thirty degrees below average are likely thanks to fresh snow cover, light winds and clear skies.
The cool temperatures look to stick around for Friday and Saturday, though plenty of mid-March sun will help buffer the unseasonably cold temperatures. Temperatures will be warming by Sunday as a ridge of high pressure ahead of our next storm moves overhead and cuts off the flow of cold air from the north, though will still stay below average and in the thirties.
This next storm is currently located near the Aleutian Islands, and is another unseasonably cold storm thanks to its origins in Siberia and the addition of more cold air from the Arctic Circle through this past work week. Forecasts call for the southern end of this storm to be forced eastward toward the West Coast in a complex manner by another cold storm currently over Japan, and we should start seeing cloudy skies by Monday as energy begins ejecting out of the storm.
The storm will also gain moisture from the subtropics as it moves across the eastern Pacific in another atmospheric river event, and while any showers that move overhead on Monday and Tuesday will be quite light, that could change by midweek if the storm evolves as currently forecast. So enjoy the beautiful weekend weather, and be sure to check back for my next regularly scheduled weather narrative on Sunday afternoon where I’ll have more details about our next winter storm.
Snow reluctantly ends to start the work week ahead of significant midweek storm
Sunday, March 12, 2023
Temperatures are around twenty degrees in the town of Steamboat Springs and mid-teens near the top of the Steamboat Ski Resort under lightly snowing skies late this Sunday morning. Light snows will continue today and reluctantly end by Monday morning, though we may see some more snow showers Monday afternoon and overnight. We will see a break in the unsettled weather on Tuesday with some sun possible ahead of a significant storm for Wednesday and Thursday.
After eight inches at mid-mountain and nine inches up top were reported Saturday morning at the Steamboat Ski Resort, brilliant sunshine emerged early in the morning and lasted through the day. But snow showers have restarted in our favorable northwest flow this morning, with three inches accumulating on the Steamboat Powdercam and two inches at the mid-mountain snow stake. Snow showers should continue through the overnight leading to a 3-6” Monday morning ski report at mid-mountain.
A weak wave passing to our south on Monday may restart light snow showers for a time Monday afternoon and overnight with 1-4” possible by the Tuesday morning report.
A break in the unsettled weather is forecast for Tuesday as a ridge of high pressure moves through the Rockies, and we should see temperatures within several degrees of our average of 41 F along with some hard-to-come-by sunshine this winter.
The nice day on Tuesday will precede our next major storm starting on Wednesday and lasting through Thursday as a cold storm currently over the Gulf of Alaska conspires with another atmospheric river north of Hawaii. As with the last storm, temperatures will be above freezing down in town after the precipitation starts early in the day Wednesday, so expect snow or a rain-snow mix turning to rain in the afternoon. Snow levels should rise to as high as 8000′, so wet and dense snowfall should be above Christie Peak.
The structure of the storm as it moves overhead Wednesday night is still uncertain as weather forecast models indicate there may some sort of split in the storm. A cold front may then stall over the mountainous terrain of north-central Colorado later Wednesday into Thursday, which contributes to a difficult snowfall prediction. We will likely do quite well from the combination of the moisture associated with the atmospheric river and the cold air from the original Gulf of Alaska storm, and my current guess is 6-12” for the Thursday morning report at mid-mountain with another 2-5” during the day Thursday.
Though the weather forecast models disagree on the details of the storm as it passes overhead, they do agree on the unseasonably cold air in the wake of the storm by Friday morning, especially if skies clear Thursday night. Unless there are big changes in the forecast, I’ll be back with my next regularly scheduled weather narrative on Thursday afternoon where I’ll discuss what currently looks like a nice start to the weekend and the following storm.
Wall of water arrives Friday
Thursday, March 9, 2023
Temperatures are in the upper twenties in the town of Steamboat Springs and low teens near the top of the Steamboat Ski Resort under clearing skies late this Thursday morning. The mostly sunny skies this afternoon will be replaced with a warm and wet Pacific air mass on Friday, possibly bringing rain below mid-mountain during the day and evening. Colder air arrives overnight Friday, turning any liquid precipitation to snow, with the bulk of the significant snow at mid-mountain and above over by Saturday afternoon. Snow showers may persist through the rest of the weekend.
The two inches of snow reported at mid-mountain today and three inches up top were due to an ejecting wave of energy and moisture from a persistent area of low pressure currently off the Pacific Northwest coast that had earlier formed an eddy. Our weather gets very interesting starting on Friday as a stream of subtropical and tropical moisture referred to as an atmospheric river combines with winds on the south side of that Pacific Northwest eddy and slams into West Coast later today.
Ahead of that, skies will continue to clear today for a mostly sunny afternoon. But we will see a warm and wet Friday after the atmospheric river dumps impressive low-elevation rain and high elevation snow on California and moves overhead. As is often the case in March, the low elevations will struggle with cold enough temperatures for snow, and rain or a rain-snow mix is likely below mid-mountain on Friday and Friday evening, with a dense 2-5” expected by sunset at and above mid-mountain.
That Pacific Northwest eddy is forecast to be forced eastward on Friday by another eddy forming in its place, and will move over our area around midnight on Friday. Much colder air will accompany the former eddy, with any liquid water turning to snow at low elevations and mountain top temperatures dropping from near thirty degrees ahead of the cold front toward ten degrees by Saturday morning. Winds will become strong and gusty along the front, though should quiet down by sunrise on Saturday. We could see another 4-8” by the Saturday morning report, with the snowfall becoming progressively less dense toward morning. And there may be another 1-4” of light and fluffy snowfall by noon.
The cold front will push the best moisture to our south, keeping the chance of snow showers going through the rest of the weekend as we are on the boundary between the warm and moist air to our south and the cold and drier air to our north. We could see 1-4” of additional snowfall Saturday night and that again during the day Sunday.
A final weak wave may move across Sunday night, and if that happens we could see another 1-4” fall in the favorable northwest flow. A ridge of high pressure then looks to briefly build over our area to start the work week ahead of the new Pacific Northwest eddy for some nice weather, though that may be short-lived as another significant storm is possible around midweek. I’ll have more details about that in my next regularly scheduled weather narrative on Sunday afternoon.
Unsettled work week ahead
Sunday, March 5, 2023
After some sun and wind and temperatures in the mid-thirties in Steamboat Springs late this Sunday morning, snows have restarted with several inches of accumulation at the Steamboat Ski Resort by late this Sunday afternoon. Another several inches are likely to fall by midnight before they taper off by Monday morning with some clearing skies advertised for parts of the day. Our area will be right on the southern edge of light snows on Tuesday and Wednesday before good chances for snow reappear starting Wednesday night and lingering through Thursday.
A sharp ridge of high pressure currently over the eastern Pacific extends through Alaska toward the North Pole while an area of low pressure is anchored off the Pacific Northwest coast near the base of the ridge. Northerly winds on the east side of the high pressure are directing waves of cold air and energy around the somewhat stationary storm, resulting in a stationary front that extends from the base of the storm eastward across northern California, Nevada, Utah and northern Colorado. This front separates the colder air to our north from the warmer air to our south.
The snows from today were the result of some energy ejecting out of the storm yesterday and moving over our area this afternoon, accompanied by the strong winds of the jet stream overhead. The bulk of the 3-6” that should be reported at mid-mountain Monday morning that has not already fallen today will fall by midnight.
Weather forecast models are not in complete agreement as to the strength and location of the ejecting waves through most of Wednesday, and we may have some light snow showers at times as the front meanders south and perhaps even some sun as the front meanders north. Any accumulations are likely to be very light, with 1-4” the best hope on the Tuesday and Wednesday morning mid-mountain ski reports, though there also may be zeros reported.
Weather forecast models agree that a stronger wave of energy moves overhead by Wednesday night even as cold air from the northern latitudes replenishes the storm through the work week and beyond. Unfortunately, they disagree about the details, with the American GFS faster, stronger and wetter. That model is currently predicting as much as 6-12” between Wednesday night and Thursday afternoon, though the European ECMWF, which I’m currently inclined to support since it has forecast this weather setup more accurately so far, has less than half of that.
A break in the unsettled weather is forecast by both models for at least some of Friday, and agree about some sort of storm for the weekend, though they disagree on how that storm may evolve. So be sure to check back Thursday afternoon where I’ll have more details about the possible weekend storm and what may be a break in the unsettled weather pattern for the beginning of the following work week.
