Snow likely mid weekend
Thursday, December 21, 2023
Cloudy skies with temperatures in the mid thirties are over the Steamboat Springs area early this Thursday afternoon after a sprinkling of graupel, or snow pellets, last night. Clouds will grudgingly give way to some sun later this afternoon, with more on Friday, before snow chances increase from Saturday afternoon into Christmas Eve Day. And we can start looking forward to longer days starting tomorrow as the longest night of the year will be tonight as the winter solstice occurs at 8:27 pm.
An eddy of low pressure currently sits off the southern California coast while a developing storm is moving across the Gulf of Alaska. The Gulf of Alaska storm is forecast to cross the Pacific Northwest coast midday Friday while prompting the eddy to move across the Desert Southwest, and there is still weather forecast uncertainty as to how much interaction occurs between these two storms as they both move across Colorado this weekend.
There is reasonable weather forecast model consensus that the northern storm will drag a cold front through our area Saturday night, with moderate to even heavy snowfall possible at times. Ahead of that cold front, mild conditions are forecast to persist with high temperatures in the mid to upper thirties, which are between five and ten degrees above our average of 29 F. Thanks to the blanket-like insulation from overnight clouds, low temperatures will be in the upper teens and low twenties through Sunday morning, which are well above our average of 5 F. Both high temperatures on Christmas Eve Day and low temperatures on Christmas morning will cool by about ten degrees.
There is still no consensus, however, between the weather forecast models as to how much interaction occurs between these two storms, with uncertainty highest during the day Saturday and again Sunday. More interaction between the northern and southern storms will start the snows earlier on Saturday and keep them lingering into Sunday, while less interaction leads to almost all of the snowfall occurring Saturday night.
My best guess at this point is at least some interaction between the storms will occur, with snow showers from the southern storm leaving relatively dense snow starting by Saturday afternoon. Snows will continue overnight and become moderate to heavy at times, and less dense and fluffier, as the cold front associated with the northern storm moves through.
We could see 4-8” for the Sunday morning ski report at mid mountain, with another 1-4” possible in the morning as winds turn to be from our favorable northwest direction overnight. The snows should end by Sunday afternoon as a ridge of high pressure builds over the West behind the departing storm, with cool and partly sunny weather forecast for Christmas Day.
We may see a grazing and dry cool front around Tuesday, but the ridge of high pressure looks to hang around through much of the holiday week. There may be a chance for unsettled weather as we approach the new year, so be sure to check back for more details about that possibility in my next regularly scheduled weather narrative on Sunday afternoon.
Some hope for unsettled weather after midweek
Sunday, December 17, 2023
Temperatures are approaching twenty degrees in Steamboat Springs under brilliant sunny skies this Sunday noon. Some clouds will begin passing overhead tomorrow and may moderate the single digit low temperatures over this past weekend, but there is no hope for precipitation until after midweek when an unsettled weather pattern may begin.
A ridge of high pressure currently sitting over the West is bookended by a deep trough of low pressure beginning to affect the entire East Coast and an eddy of low pressure off the coast of California. Our low and high temperatures have been five to ten degrees colder than I forecast last Thursday as a stubborn temperature inversion sits over the Yampa Valley. A temperatures inversion occurs when temperature increases with elevation, thanks in our case to cold air pooling in the valleys, and is maintained by low sun angle, snow cover, light winds and clear nighttime skies.
The jet stream is also very strong between a couple of storms that currently sit over the Bering Sea and eastern Siberia. A piece of the Bering Sea storm is forecast to mix with some cold air moving through the Bering Strait and head south to dislodge the California eddy before taking its place as another eddy.
While the first eddy is forecast to move over the Pacific Northwest on Tuesday, after another mostly sunny Monday we may see some clouds skirting its southern end by Monday night that will raise our low temperatures back above our average of 6 F by Tuesday morning. And our high temperatures should reach between five and ten degrees above our 29 F average starting Monday afternoon.
Energy ejecting out of the replacement eddy will then keep passing clouds overhead for Tuesday with better cloud coverage for Wednesday. By Thursday, a piece of the Siberian storm that broke away earlier in the week is forecast to approach the eddy off the California coast and dislodge it by Friday. A piece of energy is forecast to eject from the eddy ahead of that and may bring a chance of snow showers as it passes overhead during the day Thursday, with meager accumulations at best.
Weather forecast models agree that the Siberian storm will remain distinct from the ejecting eddy early in the weekend, but are very inconsistent both between and with themselves as to how much interaction between the eddy and storm occurs over the Great Basin. Current forecasts for Christmas Eve Day vary between a dry cold front and the beginnings of a multi day storm.
Enjoy what will be a gorgeous start to the work week, and be sure to check back to my next regularly scheduled weather narrative on Thursday afternoon where I should have more clarity on the Christmas weekend weather.
Gorgeous weekend ahead
Thursday, December 14, 2023
After the fog layer dissipated this morning, temperatures are in the mid twenties under brilliant blue skies in Steamboat Springs this Thursday noon. Warming daytime temperatures and continued sunny skies will last through the weekend and into the following work week.
A storm currently crossing into New Mexico from Arizona in the form of an eddy has brought snow to southern Colorado and New Mexico, but is too far south for anything but some cool air over our area. Temperatures should approach the mid thirties today in town, which is around five degrees above our average of 30 F under sunny skies.
The skies will remain clear through the weekend as a ridge of high pressure builds over the West behind the departing eddy that will eventually bring misery to the East Coast starting late in the weekend and ahead of a strong storm currently developing in the Gulf of Alaska.
Clear skies under the ridge of high pressure will allow nighttime temperatures to fall into the low teens through the weekend, around five degrees above our average of 6 F. Interestingly, mountain top low temperatures might be several degrees warmer as cold air pools in the valleys, leading to a morning temperature inversion where temperatures increase with elevation.
Continued sunny skies will battle the cold air mass brought overhead by the eddy to our south through tomorrow for another day similar to today. And eventually, the sunny skies will allow high temperatures to rise another five degrees for Saturday and Sunday with another degree or two added for the beginning of the work week.
Meanwhile, that Gulf of Alaska storm is forecast to elongate to the south and split, with the southern end forming a large eddy that is forecast to briefly loiter off the coast of California. The bulk of this eddy is forecast to eventually eject across the Pacific Northwest next week, with only clouds likely affecting our area around next Tuesday.
Otherwise, quiet weather looks to persist into Christmas weekend when the long range weather forecast models offer some hope of snowfall. So while we all enjoy the gorgeous weather ahead, I’ll be monitoring the long term periods and have more to say about a possible pattern change in my next regularly scheduled weather narrative on Sunday afternoon.
Snows to last through Monday ahead of dry skies
Sunday, December 10, 2023
Temperatures are approaching twenty degrees with light snow falling in Steamboat Springs this Sunday mid afternoon. The snows will continue through Monday even as temperatures warm into the thirties before stopping by Tuesday. But even though the precipitation stops ahead of a dry period that looks to last past next weekend, clouds look to hang around through midweek before some sun reappears by Thursday and beyond.
The main part of the storm that produced a three day total of 17” at the Steamboat Ski Resort is currently over the Appalachians which leaves our area in moist and favorable northwest flow. The reason winds from the northwest are favorable is that they are lifted as they encounter the north-south oriented Park Range in a process called orographic , or terrain-driven, lifting. Ideal conditions for accumulating snowfall are then rounded out by some cold air, which makes the atmosphere unstable and adds to the lifting, some storm energy which also adds to the lifting, and of course moisture.
While winds from the west can also produce significant orographic snowfall, they tend not to have the cold air associated with winds from the northwest which negatively affects atmospheric stability and snow crystal shape. Additionally, and well known by those who ski here, westerly winds impinge directly on the predominantly westward facing mountain which can create substantial, but wind affected snow.
These northwest orographics will force another round of accumulating snowfall that will begin in earnest tonight and last through Monday. Though temperatures are forecast to warm into the mid thirties on Monday, which is around five degrees above our average of 31 F, the remaining three ingredients for orographic snowfall remain through the day Monday as a couple of waves in northwest flow pass overhead tonight and again later in the day Monday.
I know I mentioned an inch or two of accumulation in the last Thursday weather narrative, but both the wave and moisture tonight are more robust in the latest weather forecast models, and we could see 3-6” of snow for the Monday morning report with another 1-4” during the day and evening.
Meanwhile, a wave forecast to cross the Pacific Northwest coast on Monday is forecast to develop into an eddy that travels through Nevada on Tuesday and into Arizona on Wednesday. Our winds will shift to be from the west on Tuesday and south on Wednesday which will cut off our moisture supply and raise temperatures to the upper thirties by Tuesday and around forty degrees for Wednesday. Clouds look to stick around through Wednesday thanks to the eddy to our southwest before there is a chance for some sun on Thursday.
Unfortunately, weather forecast models agree that a ridge of high pressure builds over the West behind that departing eddy, so mostly sunny skies and temperatures warming to the low forties are likely for next weekend, and perhaps through at least part of the following work week. But that is over a week away, and forecasts can change, so check back to my next regularly scheduled weather narrative on Thursday afternoon for an updated look at the weekend weather and when the chance of storms might return.
Snows to continue into the weekend
Thursday, December 7, 2023
Light snow showers with temperatures in the mid thirties are over Steamboat Springs this Thursday mid afternoon. The stronger portion of this two part storm arrives on Friday along with a cold front around noon bringing moderate to sometimes heavy snow showers that will persist through the evening before tapering off Saturday morning. While we may see some sun early Sunday, a storm may graze our area later in the day that might restart light snow showers that last into the overnight.
A cold storm from the Gulf of Alaska is on the move with the main piece of the storm currently bringing precipitation to the northern half of the West Coast. A leading piece that was ejected out of the storm earlier is grazing our area to the north, and has left about an inch at the mid mountain powdercam and almost twice that up top so far.
There may be some additional showers later today and overnight, or not, as the short term weather forecast model has the best accumulations to our north. But the main piece of the storm moves through our area on Friday along with a cold front current timed for late morning or early afternoon, and we could see 3-6” during the day and an additional 3-6” overnight for a 6-12” mid mountain Saturday morning ski report.
Temperatures are on a downtrend thanks to the cold air associated with both pieces of the storm, with high temperatures in the upper twenties on Friday and mid twenties on Saturday, which is around five degrees below our average of freezing.
If there is some clearing Saturday night as currently predicted, Sunday morning will start quite chilly with low temperatures reaching the low single digits which is around five degrees below our average of 8F.
A ridge of high pressure then tries to build over the West behind this storm system, and there is weather forecast model disagreement over a wave that moves through the ridge on Sunday and how much moisture it may contain. So there may be a chance for snow showers later Sunday and overnight, but the amounts should be only an inch or two if they occur.
There are another couple of waves moving over the West early next week, though weather forecast models disagree on whether we see snowfall chances before midweek or after. So check back to my next regularly scheduled weather narrative on Sunday afternoon where I should have more clarity about the coming work week weather.
