Forecast:
Saturday (2/8): Brief break in snow with highs around freezing, westerly winds at 20-30 mph with gusts possible up to 60 mph.
Sunday (2/9): Snowy, highs around 10 degrees, winds from the east northeast at 10 mph with gusts to 20 mph.
Forecast Discussion:
We are in the middle of a big storm cycle, but with great snow will come scary avalanche conditions. From an avalanche perspective, there are three bad elements to the storm. First, it is big. Second, it is upside down (storm starting cold and ending warm). Third, it will be very windy during the storm. That’s a very bad combination avalanche-wise. As this is a weather forecast and not an avalanche forecast, I’ll stop talking about the avalanche issues now, but please be extra careful out there this weekend.
Here comes the snow! As I’ve written before, our patrol backcountry area tends to get snow in one of three ways, in descending order of importance. (1) A favorable wind direction (east is best) coupled with moisture creating orographic lift. (2) A strong enough storm from an unfavorable direction (for example, from the west) so we fall within the spillover effect. (3) Bands of snow caused by jet streaks or other upper atmospheric phenomenon.
This Thursday / Friday storm is a strong and potent combination of #2 and #3. As #3 (jet streaks) are rather temperamental, take all forecasts involving them with a grain of salt. (Yes, you should take all forecasts with a grain of salt, but with jet streaks you should take the forecast with a really big grain of salt.) The models have had significant disagreements with each other (and with themselves between each run) on storm totals and storm timing – but the models have consistently agreed this will be a significant storm. (Their disagreement as to what happens in the Boulder / Golden corridor has been even more extreme.) However, now with the storm more than halfway over, clarity is starting to appear.
So far, Eldora is reporting 12”. Near to but outside of our patrol zone, Loveland is reporting 15” and Winter Park is reporting 11”. Considering the winds, snowfall reports must be taken with some caution, and they may be either overestimates or underestimates. That said, you don’t ski the snow stake, and skiing should be good regardless of exact amounts.
Today, snow continues. Between now (6 am) and Saturday morning, the models are predicting an additional 4-8” of snow. (Specifically: 8” per HRRR, 7” per the Canadian Model, 6” per the European Model, 5” per WRF Model and American Model, and 4” per the NAM Model.)
Snow tapers off by daylight on Saturday. The sun may even poke out briefly on Saturday per a few models, but the winds from the west will remain strong.
The next system may be bigger (and sooner) than my last forecast predicted, which means we’ll have a snowy and cold Sunday. The major models are predicting the system will come in two waves, the first overnight from the west and the second, in the afternoon, with winds from the east northeast. Sunday snow totals of 7” per the WRF Model, 5” per the Canadian Model, 3” per the European Model, 2.5” per the American Model, 2” per the NAM Model. Higher totals likely in the Rock Creek area of our patrol zone.
There may well be a few more inches of snow on Monday. After Monday, a warm-up starts later in the week, with the next rolling in next Friday or Saturday.
If anyone wants to join me for an Eldora Sidecountry Patrol Day on Sunday, please reach out to me directly. With new snow and high avy danger, probably the south southeast side of Bryan Mountain will be where I’ll be.
-Jordan (Friday morning)
Note: Unless otherwise noted, all forecasts are for 10,000’ in exposed areas. References to American Model are the American (GFS) Model. References to the Canadian Model are the Canadian (GDPS) Model. References to the WRF Model are the CAIC WRF Hi-Res Model. References to the European Model are the European (ECMWF) Model.
