Cold front to arrive tonight with some snow Monday and Tuesday
Sunday, December 8, 2024
A broken cloud deck ahead of a strong cold front tonight is over the Steamboat Springs area this Sunday noon with temperatures only in the low twenties. Dry air just ahead of the front should lead to mostly sunny afternoon skies, but we could see snowflakes as soon as tonight, with most of the accumulations behind the front occurring between Monday and Tuesday noon. A ridge of high pressure then temporarily builds to our west while a storm deepens over the Midwest keeping winds from the northwest and a mix of sun and clouds overhead through the rest of the workweek.
A splitting trough of low pressure extends from the Pacific Northwest through Montana, with the western half of the split forecast to move southward through the Great Basin, bringing a cold front through our area tonight. While we should see mostly sunny afternoon skies ahead of the front, snowflakes could be associated with the front tonight. Sadly, the short-range weather forecast models disagree on snowfall amounts for the entire duration of the storm through Tuesday afternoon, forcing my admittedly broad snowfall estimates.
There could be an inch or two of snow reported at mid-mountain Monday morning at the Steamboat Ski Resort based upon the more optimistic model, though accumulating snowfall will more likely wait until after the report with 1-4” possible by sunset as winds turn to be from the favorable northwest direction behind the front. But there is not a lot of moisture associated with the front, and combined with an even drier reinforcing surge of cold air early Tuesday, there could be another inch or two overnight Monday and 1-4” during the day Tuesday.
Ironically, the cold front will break the strong temperature inversion in the Yampa Valley, with low temperatures in town rising from the low single digits to the low-teens, finally above our average of 7 F. But the relief will be brief as high temperatures behind the front on Monday and Tuesday are only expected to be in the high teens or low twenties, over ten degrees below our average of 31 F.
By Wednesday, a ridge of high pressure is forecast to build temporarily over the West Coast. Our storm will recombine with the eastern half of its split and more cold air from the Canadian Plains, producing a deep and cold area of low pressure over the Midwest. The resultant northwest flow over our area will contain some moisture keeping the cool air, average temperatures and a mix of sun and clouds around through Thursday.
Meanwhile, incoming Pacific energy is forecast to cross the West Coast on Thursday and move the ridge toward our area while weakening it, likely keeping our area dry. However, more incoming Pacific energy may bring snowfall chances back to our area next weekend or soon after.
Let’s hope for the more optimistic side of the early week snowfall forecast, and check back to my next regularly scheduled weather narrative on Thursday afternoon for more details on what we may expect for next weekend.
Beautiful weather to continue through Saturday
Thursday, December 5, 2024
Another bluebird day is over the Steamboat Springs area this Thursday noon with temperatures in the mid-twenties in town and upper-twenties near the top of the Steamboat Ski Resort. Similar weather is expected through Saturday before an incoming storm brings precipitation chances as early as Sunday and colder temperatures for Monday and Tuesday.
A ridge of high pressure is currently over most of the West while a large storm is located over the Aleutian Islands. Energy ejecting from the storm will weaken the ridge of high pressure and allow the storm’s remnants to begin affecting the Pacific Northwest on Saturday as it moves across the Gulf of Alaska. That means continued beautiful weather through at least the beginning of the weekend, with cold mornings in town thanks to the persistence of a temperature inversion caused by clear nighttime skies, calm winds and recent snow cover.
The storm is expected to mix with cold air from western Canada and split as it moves through the Great Basin on Sunday, with weather forecast models indicating uncertainty regarding how much cold air makes it over our area on Sunday. The larger-scale and longer-term models have the cold air staying away from our area on Sunday, while the medium-scale, medium-term model have a cold front moving through by Sunday afternoon.
We will see snow with the cold front, whether it moves in on Sunday or Monday, though amounts at this time look quite modest due to the quick movement of the storm and its limited moisture. What is more certain is that the cold front will first break the low-level temperature inversion thanks to increased winds and the resultant mechanical mixing which brings warmer air aloft down to the surface. But any relief will be short-lived as the very cold air settles overhead on Monday and Tuesday, with high temperatures in town only in the low-twenties or high-teens, well below our 31 F average.
I’m reserving a snowfall guess for my next regularly scheduled weather narrative on Sunday afternoon as forecast amounts are inconsistent both between and within the various weather forecast models. Until then, be sure to enjoy this stretch of beautiful early-December weather.
Temperatures to slowly warm under mostly clear skies
Sunday, December 1, 2024
Clear skies and temperatures in the twenties are over the Steamboat Springs area this Sunday noon on the first day of December, the start of meteorological winter. Quiet and cool weather will persist through the workweek with little hope for precipitation until or just after next weekend.
A ridge of high pressure is over most of the West Coast while a deep and broad area of low pressure is over eastern North America. Our area is under predominantly northwest flow as light winds round the top of the ridge and move toward the eastern low pressure area. Though an area of dry low pressure is slowly spinning well off the southern California coast, weather forecast models have that staying south of our area as it moves inland through the workweek.
The clear skies, light winds and fresh snow cover have led to a strong temperature inversion, where higher elevations are warmer than the cold Yampa Valley bottom. For example, the low temperature at the Storm Peak Lab near the top of the Steamboat Ski Resort was 15 F this morning compared to one degree at my weather station near the resort’s base. At least the low temperature this morning was warmer than the frigid -7 F Saturday morning and -10 F on Friday morning!
Temperature guidance is notoriously too warm under these conditions as weather forecast models struggle with the low-level details, with the low temperatures running ten to fifteen degree below forecast and high temperatures around five degrees below forecast. So we are probably looking at continued single digit lows, about five to ten degrees below our average of 11 F and mid-thirty degree highs, just above our average of 34 F.
Ironically, the best chance of breaking a persistent inversion is an incoming cold front, as winds associated with the front mechanically mix the low-level atmosphere and bring the warmer air aloft down to the surface. While only weak and dry grazing waves in the northwest flow are forecast for Monday and Wednesday, a better chance of some mixing may exist for the end of the work week as a wave of energy is ejected from a strong storm forecast to develop over the Aleutian Islands.
While this currently looks weak, dry and disorganized, a wetter and stronger wave from the Aleutian storm may bring a storm through our region near the end of the weekend or the beginning of the following workweek. So enjoy the sunny but cool week and I’ll have more details about the incoming storm in my next regularly scheduled weather narrative on Thursday afternoon.
Dry and warmer weather to arrive for the weekend
Thursday, November 28, 2024
After some magical flurries early this Thanksgiving morning in Steamboat Springs, the sun has appeared, illuminating a sparkling wintry landscape. Sixteen inches was officially recorded at the downtown weather station by Wednesday morning with around two feet at the Steamboat Ski Resort by Wednesday afternoon. The cold air behind the storm will keep the high temperatures in town in the twenties today before they slowly rise through the weekend toward forty degrees by Monday under mostly sunny skies.
The atmospheric river and the remnants of the bomb cyclone delivered as promised, with the sixteen inches of snow in town since Monday night containing almost one and a half inches of liquid water for a very dense 10:1 snow water equivalent. In hindsight, the storm arrived about six hours earlier than forecast in my last weather narrative, making Tuesday morning snowier than expected while allowing the storm to end earlier on Wednesday. And while the snow totals forecast for the Steamboat Ski Area were close, the snowfall in town was under-predicted by around fifty percent, likely due to the stronger-than-forecast forcing from the former bomb cyclone.
A ridge of high pressure currently over the eastern Pacific ahead of a large storm developing south of the Aleutian Islands will slowly strengthen as it moves eastward through the weekend. Combined with a deep area of low pressure over eastern North America, winds from the northwest will carry predominantly dry and warmer air overhead through the weekend. A weak wave embedded within this flow will bring some clouds overhead on Saturday, especially in the afternoon, but that will not stop high temperatures forecast to be in the mid-twenties today from slowly rising through the weekend toward forty degrees on Monday, compared to our average of 36 F today and 34 F on Monday.
The dry and warmer-than-average weather looks to continue through the workweek, though there is some hope that we may see some precipitation by next weekend or soon after. However, there is considerable uncertainty in the longer-range forecast, so enjoy the beautiful weather for the long Thanksgiving Day weekend and check back to my next regularly scheduled weather narrative on Sunday afternoon for more details.
Monster storm to start Tuesday after moderate storm today
Sunday, November 24, 2024
Light snow is falling in Steamboat Springs late this Sunday morning with temperatures hovering in the low thirties. A cold front will bring moderate snowfall accumulations through tonight preceding a break in the weather on Monday. But it will be short-lived as moderate to heavy snows on Tuesday and Wednesday bring significant accumulations to all elevations making travel difficult or even impossible at times over Rabbit Ears Pass.
A wave of energy ejected from the decaying bomb cyclone off the Pacific Northwest coast will combine with the remnants of an atmospheric river and bring a cold front and moderate snow through our area this afternoon and evening. Total accumulations should be between four and eight inches at and above mid-mountain with one to four inches in town.
A break in the weather on Monday will bring mostly sunny skies with high temperatures in the mid-thirties, around our average of 37 F. But don’t be fooled by the nice day; the Pacific Northwest storm is forecast to move slowly south through Monday before grudgingly being forced eastward by a wave of energy and cold air moving across Alaska. Additionally, another atmospheric river moving across the southern Sierras, much wetter than the last, will be ingested by the storm as it approaches our area early Tuesday.
Light snow should start falling after midnight on Monday before the firehose of moisture produces moderate to heavy snows thanks to westerly winds impinging on the Park Range. Snowfall rates around an inch per hour and increasing winds with gusts above 30 mph will make travel hazardous over Rabbit Ears Pass by Tuesday afternoon.
The storm will stretch to the southwest as it moves across the Great Basin later Tuesday, bringing a moderate cold front that will force even heavier snowfall rates approaching two inches per hour at times. Travel over Rabbit Ears Pass will likely degrade further and perhaps become impossible from later Tuesday into Wednesday morning.
The heaviest snowfall should be over by Wednesday afternoon, though snowfall will likely linger through Thanksgiving morning as the rest of the stretched storm passes overhead. Total snowfall accumulations will be impressive, with mid-mountain and above seeing 1-2′ by Wednesday morning and another 6-12” by Thanksgiving morning. The warmer temperatures in town, especially Tuesday afternoon with high temperatures just above freezing, will limit the accumulations to 3-6” by Wednesday morning with another 1-4” during the day and overnight.
There may be some sun by Thanksgiving afternoon illuminating the new wintry landscape, especially in town, as a ridge of high pressure ahead of a strong storm forecast to develop south of the Aleutian Islands moves eastward. There is some weather forecast model uncertainty regarding a wave moving around the periphery of the ridge that may bring cooler air and snow showers by Friday or Saturday, but I’ll have more details about that in my next regularly scheduled weather narrative Thursday afternoon.
