Sunday, December 29, 2019
The cold temperatures in Steamboat Springs continue this Sunday afternoon, with a high temperature of -2 F at the summit already observed at 12:40 pm and the current 14 F in town likely at our high for the day. Lingering snow showers will end today, though the cold will stick around ahead of a promising storm that begins on New Years Day.
Currently, our early weekend storm has moved into Minnesota and strengthened, and the cold northerly flow on the backside of the storm is keeping our temperatures cold, with the 14 F in town twelve degrees below our average of 26 F. The light and barely-accumulating snow showers seen today will end by midnight as we are between the storm in Minnesota and another one currently dropping southward along the West Coast that will not affect our area.
There will be some clearing of the clouds overnight and through Monday, and this is important to the low temperature forecasts for town as any clouds insulate the surface of the earth like a blanket. Though it will be cold in town tomorrow morning, with temperatures at least five degrees below our average of 3 F, clearing skies would allow temperatures in town to fall to ten or even fifteen degrees below average.
There should be more sun for Monday, in spite of the possibility of high clouds, and though mountain temperatures will warm by five degrees or so from Sunday, they will remain cold as the cold northerly or northwesterly flow persists.
Drier air invades our area later Monday, and the fresh snow cover, light winds and clear skies will allow the valley temperatures to plummet into the negative teens for Tuesday morning. This will create a temperature inversion, where temperatures increase with elevation. While the mountain temperatures will still start cold near 0 F, they will still be warmer than the temperature at the base.
But along with sunny skies on Tuesday, the atmosphere will warm through the afternoon, allowing temperatures to move into the teens both on the hill and in town for a gorgeous mid-winter day.
Clouds increase New Years Eve ahead of a promising storm out of the northwest slated to begin snows over our area during New Years Day. There is a lot to like about this storm; it’s cold, it’s moist and it’s northwest trajectory is favorable for snow over Steamboat. I mentioned to some of the nice ticket-checking folks at the base of the gondola building yesterday that the storm looks too good to be true, but if it evolves as currently predicted, light snow early on Wednesday should turn moderate to heavy by the afternoon and continue overnight as first a cold front passes through and is then followed by orographic, or terrain-driven, snows.
Though there are some indications in the weather forecast models of the storm undergoing a minor split as it passes over our area, 6-12” of light and fluffy snow could be reported on the Thursday morning mid-mountain report, with light to sometimes moderate snow showers continuing through the day and into Friday morning leaving another 3-6” by the Friday morning report.
Another wave in northwest flow will keep snow showers going during the day Friday and into Saturday morning, though the atmosphere warms and stabilizes and limits the accumulations.
There is forecast uncertainty with respect to a ridge of high pressure that may briefly build over our area for part of the weekend, though weather forecast models agree on another northwesterly storm by later in the weekend or early the next week.
As an administrative note, while I normally publish these weather narratives on Sunday and Thursday afternoons, I do adjust this schedule based upon storms, so there may be a Wednesday afternoon discussion.
Thursday, December 26, 2019
Behind the modest Christmas Day storm in Steamboat Springs yesterday, a mix of sun and intermittent snow showers will continue today before we see more sun for Friday morning. But a much colder air mass is forecast to settle over our area for the weekend and heading into the new year with snows likely on Saturday that could persist through Monday.
In hindsight, the Christmas Day storm was disappointing to me as there were indications in a couple of models over several cycles that three bands of snow would pass over the Steamboat Springs area; in fact only one passed through mid-morning which did produce a quick two inches of snow. The afternoon band looked threatening for a while, though all we saw were clouds on the upper mountain, with some sun in the South Valley, and the evening band failed to materialize.
Even though my forecast numbers did verify on the lowest end, that the shorter-range models over-predicted the later-day snowfall is troubling from a forecasting perspective. In broad terms, the storm placement to our south never produced the favorable northwest flow for our area, so the forecast was too reliant on the evolving dynamics of the storm in the generally unfavorable flow for our area.
Moving on, another Pacific storm is currently affecting southern California and will move across the Desert Southwest on Friday. Additionally, a separate fast-moving Pacific storm currently near Vancouver has mixed with some very cold air from Alaska and western Canada. From tonight and through the weekend, the Vancouver and Desert Southwest storms will interact in a complex and hard-to-predict fashion over the West. While snow amounts for our area could surprise to the upside or downside, the cold temperatures on Saturday, Sunday and Monday are more certain.
So, some sun Friday morning should give way to increasing clouds as the Desert Southwest storm moves across Arizona. Snow showers should get going Friday night as the first cold front from the Vancouver storm moves through, with 1-3” possible for the Saturday morning report. Temperatures should fall through the day in cold northerly flow, approaching around 0 F by the time the lifts stop turning on Saturday, along with continued light snow showers that would leave another several inches.
Snows will persist overnight and into Sunday morning, leaving 2-5” of powder for the quite cold Sunday morning report. While they may end for a time during the day Sunday, light snow is forecast again from Sunday afternoon through Monday morning, with 1-4” of snow possible for the still-cold Monday morning report.
We should see another cold Tuesday morning, though temperatures should moderate during the day, especially at the higher elevations. There may or may not be snow showers for New Years Eve as a good-looking storm from the Pacific Northwest approaches. This is currently forecast to bring accumulating snows to our area for New Years Day, and I hope to have more clarity on this storm by my next weather narrative on Sunday afternoon.
Tuesday, December 24, 2019
A quick note to update my forecast from last Sunday for more snow. Shorter-range models have indicated the possibility of banded snowfall on Christmas Day over Steamboat Springs, which could create snowfall rates as high as 1” per hour at times tomorrow. The banding can occur when the usually broad and diffuse lift associated with an unstable atmosphere within a storm is concentrated along relatively narrow and roughly parallel bands, and can result in localized moderate to heavy precipitation at times.
I still expect the storm to get going this evening, with 1-4” expected by the Christmas Day ski report. But after a break early in the morning after the initial wave of the storm passes through, we should see sometimes moderate to even heavy snowfall at times from mid-morning through the afternoon leaving another 2-5” of snowfall at mid-mountain by the time the lifts stop turning.
While the heaviest snowfall will be over by around midnight on Wednesday, with another 1-4” overnight yielding 3-9” for the Thursday morning report, much lighter snows will continue through the day Thursday with only minor additional accumulations expected.
Drier air briefly works into northern Colorado on Friday before a quick moving Pacific wave mixes with some very cold air from Alaska and western Canada and brings sharply colder temperatures for the weekend. Currently, light snow showers are advertised for at least Saturday and possibly Sunday as well, but I’ll have more details on the weekend’s weather on my regular Thursday afternoon weather narrative.
Sunday, December 22, 2019
Some morning clouds have given way to mostly sunny skies in Steamboat Springs this Sunday around noon, with the current temperature in town one degree above our average high of 27 F and the temperature at the top of the Steamboat Ski Area a balmy 37 F, accompanied by some breezy southwest winds.
The warm temperatures are a result of warm air being carried northeastward ahead of a large storm just off the northern California coast. The storm is expected to split tonight as additional Pacific energy approaches and forces the storm eastward on Monday and Tuesday. The evolution of this storm has varied within and between the weather forecast models over the last several days, making for an uncertain forecast. Right now, Monday looks similar to today, with Tuesday seeing increasingly thick cloud cover ahead of the storm in continued above normal temperatures. Snow showers are currently advertised to break out Tuesday evening, perhaps around midnight, with 1-4” of snow expected for the Christmas morning ski report as a cool front passes through.
Snow showers are expected to persist through Christmas Day into Thursday as additional Pacific energy interacts with the storm. Though generally of light intensity, there is a possibility of better snowfall for a time Wednesday afternoon and overnight as a wave of energy that is forecast to eject out of the storm may or may not pass close to our area. So there could be another 1-4” for the Thursday morning report.
A break in the unsettled weather is likely for later Thursday or Friday that extends through most of the upcoming weekend before significant weather forecast model disagreement appears. The American GFS want to keep the storm moving well to our south with a dry and cool forecast for the beginning of the next work week, while the European ECMWF hangs the storm far enough back to bring light snow chances back to our area. More details should be available by my next weather narrative on Thursday afternoon.
Thursday, December 19, 2019
The weather will stay dry in Steamboat Springs with continued warming through the Winter Solstice weekend, which occurs at 9:19 pm on Saturday and makes that night the longest of the year. Warm and pleasant weather will last through Monday before several waves of Pacific energy and moisture turn our weather unsettled starting around Tuesday, Christmas Eve day.
After a relatively warmer morning in town with a low temperature of 2 F this Thursday, just two degrees below average, an anemic and moisture-starved wave will pass over the Rocky mountains today, barely bringing even clouds to our area. However, some cool air associated with the wave will keep temperatures in check today and create another chilly morning in the Yampa Valley for Friday. But warming commences during the day and increases through the weekend and into Monday under mostly sunny skies as a ridge of high pressure builds over the West ahead of a Pacific storm expected to affect California late Saturday and Sunday.
The evolution of this storm has not been well-forecast so far, with a lot of inconsistencies both between and within successive weather forecast model prognoses. This is not unusual with storms off the West Coast that will be affected by additional upstream Pacific energy and are forecast to mix, to some degree, with cold air from western Canada. The differences arise from not only the paucity of data over the Pacific Ocean, but also how the weather forecast models incorporate those data.
This is a long way of saying that there is considerable uncertainty in the timing and strength of storms passing over our area as soon as Tuesday, Christmas Eve day. There is a lot of time for the weather forecast models to iron out their differences by my next weather narrative on Sunday afternoon, but currently the storm is expected to undergo some sort of split by the end of the weekend even as additional Pacific energy rounds the base of the storm.
Clouds will increase later Monday into Tuesday as moisture is drawn northward over our area in southwest flow ahead of the storm. Snow showers are currently advertised to break out during the day Tuesday and last overnight before ending by Christmas as a cool front passes through.
After a likely break on Thursday, another couple of storms are forecast for around the Thursday/Friday and Saturday/Sunday time frames, though their speed and track are too uncertain for a forecast at this time. Check back for my next weather narrative on Sunday afternoon for more details.