Thursday, October 11, 2018
The active weather pattern over the western states continues through this weekend before warmer weather appears after a very wintry Sunday and cold Monday. Currently this Thursday afternoon, the temperature in Steamboat Springs is over 20 degrees below our 60 F average, and it feels even cooler than that with precipitation falling ahead of the next weather feature tonight.
A cold front will pass through northern Colorado this evening, turning the current cold rain showers into snow before ending around midnight. We will get a welcome break in the precipitation for Friday and Saturday as the sun returns and temperatures rebound, though they will still stay below average.
But very cold air is forecast to arrive for Saturday night, or as early as Saturday afternoon, as a wave of Pacific energy moves over a ridge of high pressure off the West Coast and mixes with some cold western Canadian air. Weather forecast models have struggled with the westward extent of the snow, with some initially keeping the bulk of the precipitation along the Front Range, but current trends indicates snowfall with the front Saturday night and at least some snowfall for most of Sunday in the cold, moist and unstable northwest flow behind the front. Temperatures in the valley will struggle to reach the thirties and the snow at higher elevations should be relatively low-density and powdery.
Snowfall will taper off through the day, but will be followed by an even colder blast of dry air Sunday night into Monday morning, with low temperatures possibly falling into the single digits to start the work week!
It will take some time for temperatures to recover after Monday’s very cold start, but the ridge of high pressure off the West Coast is forecast to move inland early in the work week, and this will bring warming temperatures closer to, but still below normal, starting Tuesday and lasting through the following weekend.
Normally, I would expect sunny skies with this warmer weather, but a piece of the weekend storm that initially gets left behind off the southern California coast briefly mixes with the former hurricane Sergio. While the bulk of Sergio looks to travel across New Mexico during the weekend, the leftover West Coast storm is forecast to slowly drift over the Desert Southwest and then to the northeast as the work week wears on, and we may see some clouds and cooler temperatures associated with that as the weak storm approaches.
Sunday, October 7, 2018
The weather over the Steamboat Springs area, indeed much of the west, will be influenced this upcoming week by a number of weather systems, including the current large storm in the Great Basin this Sunday afternoon, additional waves of Pacific energy traveling through the Gulf of Alaska and mixing to some degree with cold western Canadian air, and hurricane Sergio, currently over 1000 miles west-southwest of the southern tip of Baja. If that sounds like a lot is going on in the atmosphere, it is, and leads directly to uncertainty in the weather forecast for this upcoming week.
The weather this Sunday ended up being on the warm and dry side of last Thursday’s forecast, as the Great Basin storm ended up far enough south for southerly winds in advance of the storm to carry warmer and drier air northward over our area. The storm is forecast to slowly weaken and move to the northeast over the next two days, with good chances for rain tonight and Monday as the storm nears, with snow confined above 9000′ - 10000′.
The cool air will take its time getting here though, with current weather forecast models advertising a cold front moving through later Monday as the storm passes near northern Colorado and heads east of our area by Tuesday. The atmosphere will start to dry as the cool air arrives, but there may be enough moisture for some snowflakes down in the Yampa Valley Monday night or early Tuesday.
Meanwhile, a storm traveling through the Gulf of Alaska is forecast to mix with some cold western Canadian air and move into the west on Tuesday. The evolution of this storm will be quite complicated, which again leads to forecast uncertainty. Right now, most of Tuesday appears to be on the dry side with a small chance of showers in the unstable air behind the late Monday front.
Precipitation chances increase later Tuesday and Wednesday as the some of the new western storm travels eastward near northern Colorado and drags a cold front through our area. This will be the coldest air of the season so far, and could bring some accumulations to the grassy areas of the Yampa Valley on Wednesday.
Another chunk of cold air from western Canada undergoes a complicated split on Thursday, with some moving over our area for a continued chance of showers, and some staying to our west and elongating the western storm into southern California.
This part of the storm will likely interact with hurricane Sergio, which is forecast to cross the central Baja peninsula around Friday. As much uncertainty existed in the forecast to this point, even more exists for the end of the work week and next weekend when considering the track of the hurricane. The bulk of Sergio and the western storm may stay south of our area, causing a welcome warming and drying, or the storm complex may be far enough north to influence our weather next weekend.
Thursday, October 4, 2018
The Steamboat Springs area will see another wave of showers later this Thursday afternoon as the remnants of a storm to our west pass by, followed by a week of cold and wet weather as chunks of cold air from western Canada periodically move southward and mix with incoming Pacific energy over the western states.
There will be a break in the rain later tonight through Friday morning before a cold front is forecast to move through northern Colorado around noon. The front will bring sharply colder temperatures over 10 degrees cooler than our 64 F average for this date, the possibility of thunderstorms and snow levels as low as 8000′ - 9000′.
The weather will briefly clear behind the front Friday night through part of Saturday, allowing for a good view of what should be a snow-capped Mt. Werner Saturday morning, if the snow can survive the melting caused by warm ground temperatures.
More incoming Pacific energy mixes with some of the cold western Canadian air early in the weekend, producing a large storm that will move south through the Great Basin and take up residence in the Desert Southwest through early in the work week.
The evolution of this storm is uncertain, which makes the details of the weekend forecast hard to pin down. Right now, it appears some energy ejecting out of the storm should bring the chance of low elevation rain showers and high-elevation snow showers back to our area by later Saturday, perhaps as early as noon, and lasting into part of the night. What looked like continuing precipitation into Sunday may hold off for part of the day as the storm to our west trends further south in the weather forecast models. This further south solution means temperatures could be a bit warmer and the atmosphere a bit drier for a time in breezy southwesterly to even southerly flow, though weather forecast models disagree on the western extent of this warmer and drier air.
In any event, more Pacific energy and cold air from western Canada move the storm slowly eastward by early in the work week, and showers will pick up again later Sunday as ejecting energy moves over Colorado.
Precipitation should become steadier Sunday night, with snow at the higher elevations, as the slowly moving storm approaches and moves over our area through the week. Though details will change, it looks like the cold and wet weather will persist through the work week and possibly into the following weekend as additional incoming Pacific energy keeps mixing with the cold western Canadian air and re-energizing the storm. The coldest air, which will likely bring snowflakes to the Yampa Valley, looks to occur around Wednesday or Thursday.
I’m hesitant to throw this out there, but the symmetry is too good to ignore; it could be that this stormy period, which started with hurricane Rosa moving over our area, ends around or after next weekend as another hurricane is absorbed into the loitering storm and moves near our area. This then allows a ridge of high pressure off the West Coast to move inland and push the storm system to our east.