It happened. Three different respected forecasters mentioned some change could be afoot in the models. So after skiing today at Mount Rose I took the time to review the models myself, looking for something that would indicate something more substantiative than a slight chance of rain and high elevation snow early next week. That one will not be the storm we are looking for. It’s the tail end of another AR event to our north that would bring minimal amounts of rain and snow levels at 7-9k feet.
What I am interested in is the changes further down the line, where it looks like this persistent ridging we have endured could move onward, at least temporarily. That said, the Reno AFD this afternoon is being cautious about the signals:
Despite the signals for a pattern shift, confidence in the exact timing and magnitude of precipitation remains low, as highlighted in the previous discussion, and by the notable spread among the ensemble and deterministic models.
But still, I do want to point out that we have been through at least 10 days, or 40 model runs of absolutely no sign of anything but persistent ridging. The jet stream used to be more predictable, but we are again in this odd polar vortex pattern, resulting in a dipole where one half of the country is cold and stormy and the other half is not. The blocking high we see in the Pacific also has its counterpart in the Atlantic. So our ridge can’t move until the low in the east moves, which can’t move along until the ridge in the Atlantic moves along. What exactly causes these movements to hit pause once in a while is beyond my meteorology training.
There are at least two models that are in agreement here. Here’s the GIF of the GFS for pressure anomalies over the next 16 days:
Here’s the same thing, except in the Euro:
So both of those models are seeing a significant change about 10 days out, which is just entering the window of believability. The Canadian model only goes out 10 days for pressure anomalies, and in that model you see the change just beginning.
So this is better than a sharp stick in the eye…or staring at pressure anomaly maps that are all rusty brown or precipitation models that are blank white palettes showing no snowfall. It does let us at least dream of a white Christmas. I’ll take it.
Just for funzies, here’s one model run of one model showing potential snowfall through December 26th. It’s pretty to look at and dream about it, but I would not count on it. In particular, don’t book a vacation based on this one, please.
Does This Sort Of Thing Ever Happen?
If you talk to the old-timers, which might even include me, it just takes one amazing storm to completely turn things around in the Sierra. So I spent some time this afternoon looking at the actual stats for the last 53 years at Alpine Meadows. The following chart represents the 7 worst starts of the season based on November snowfall, as measured at the base of Roundhouse. These are seasons where the snowfall in November was in the single digits.
| Season | November Snowfall | December Snowfall |
|---|---|---|
| 1986-1987 | 6.0 inches | 23.0 inches |
| 1992-1993 | 6.5 inches | 172.5 inches |
| 1995-1996 | 1.0 inches | 37.5 inches |
| 2007-2008 | 2.0 inches | 58.0 inches |
| 2013-2014 | 4.5 inches | 28.0 inches |
| 2021-2022 | 3.0 inches | 191.0 inches |
| 2023-2024 | 2.5 inches | 24.0 inches |
| 53 Year Average | 33.6 inches | 69.6 inches |
So in the 53 years of accurate records at Alpine Meadows, only 7 of those seasons were seriously lacking snow which is 13% of seasons. Looking at those that had a big recovery during December that has only happened twice. There’s two ways to look at this. Two out of seven is a 28 % recovery rate, which is possible but not probable. If you considered two big recoveries out of 53 years of data, the probabilities are much less. But you would have to take a much deeper look at the statistics to make that meaningful.
I guess the point is to say that it could happen and it has happened. We hope it does happen. Don’t make your reservations just yet based on this argument. We had 14 different family members hoping to stay at Casa De Fisher for some snow fun during the upcoming holidays. I sent out a message on Monday suggesting they bring bikes instead of skis. Maybe Ma Nature is trying to show me who is boss.
Current Conditions
Not much has changed in what is available for skiing and riding since my last report. Most resorts have been unable make snow due to the inversion. Mornings this week have been at 25° at my house in the low part of Truckee and then 38° in the parking lot at Mount Rose. I did catch on the webcam that Palisades was making snow at Exhibition this morning.
I did my 14th day at Mount Rose this morning. It’s fun and skiing quite well. Honestly it all depends on how many clinics and teams are on the mountain each day. It can be overwhelming. Morning skiing and afternoon bike rides have been the routine every day. The mountain bike trails continue to be variable due to frost induced mud in shady areas. The frost has even been problematic for pavement rides lately, with the low angle of the sun. Some shaded areas are never melting, so you are getting frost building on frost building on frost. Ride with care. Out in the wide open sun it was 60° in Truckee this afternoon and the perimeter road of the airport offered a very nice ride.
I appreciate you wading through all the weather forecasts and breaking it down for all of us.
From summer forward, what I’d been reading led me to believe that this season would likely be close to 2013/14. 🙁
Thanks as always for your mountain updates!
Nice job with Bing!
This comment pertains to skiing outside the Tahoe area, so if you’re not interested, feel free to skip. I just spent three days skiing at Arizona Snowbowl, a small resort near Flagstaff with a base at elev. 9,200′ and its highest point at 11,500′. It seems to be the one resort in the Southwest that’s gotten any meaningful snow (60″ for the season). A guy on a chairlift today told me he met someone who’d traveled here from Utah to find skiable snow. How crazy is that? And another lift-mate said on opening day, Nov. 21, he skied in “knee-deep” powder. Given Snowbowl’s low latitude, that is even crazier.
Similarly to what Mark reports, the last couple of mornings at my home in a chillier-night part of Flagstaff (elev. 7,000′) were in the low- to mid-20s, but at the mountain base over 40 degrees before the 9 a.m. opening time. The magic of temperature inversions at work . Monday’s temps started out and stayed mainly in the 30s at the resort, having been colder last week, but they got to near 50 degrees by midday yesterday and today. No snow is in the forecast.
The snow quality the last few days was all over the map. It was like spring skiing but with a saving grace of low mid-winter sun so the snow did not get baked into an untenable slush by lunchtime. My years of reading Mark’s posts have taught me about ice-to-soft patterns and true enough, we morning skiers and riders were chasing sun where possible. First runs were loud, scratchy ice events unless you went for a groomed run. The corduroy was pretty decent, even early. There’s still enough snow despite what now is relentless, if low-angle, sunshine and temps 10-15 degrees above seasonal normals to avoid the rocks, especially on the main, groomed (and later skied-out) runs. I didn’t dare try the moguls, because they looked, and sounded when other skied them, like ice sculptures. By 10 or 10:30 a.m. the sun-warmed slopes softened up, and some were actually nice. I learned that parts of certain higher runs that stayed in tree shade all day also retained respectable snow quality, even early in the day. But my go-to run at the top of the resort (called Upper Ridge if you’re curious), which reliably offers soft snow through much of the season because of its high elevation, was chundery, rackety mess. I guess the freeze-thaw cycle rose up to over 11,000′.
There were next to no lift lines, so most of the time it was ski up, get your pass scanned, and hop a chair. Since I need to work when possible, I skied mornings the last thee days, then moved on to attend to other matters. Because of the absence of lift lines, I averaged 15K’ vertical in roughly 2 hours of skiing, per an app on my phone. The air is dry and during the day was very comfortable. It wasn’t sweaty like it can get in spring when your warm clothes quickly become a burden.
If that ideal scenario in the graphic above becomes reality, looks like the Tahoe area will get a good dump. Here’s to hoping that comes true.
Another area in the southwest, Wolf Creek CO has snow. They are 100% open. All trails. Sorry no first hand report.
Thank you for all the history information . I love reading about it..
Regarding the polar vortex.
My first job at Alpine was in the race department (1985) after being a 10yr ski bum. The first task was to get a Race course constructed on Kangaroo for the America Opening Cup, which was always scheduled around late November and first of December. This was a big deal event. One year, it looked really bleak, and I remember an Alpine Executive making a comment, that it had to stop raining back east, ( they were getting pounded with winter weather), before we would get snow. Well sure enough. It stopped raining back east, and we got enough snow the construct the course! That pesky Polar Vortex!!!
8 of the last 9 runs of the GFS have kept large amounts of moisture in the forecast for the sierra for xmas week.
i know it’s still fantasy land but it’s looking more probable.
Honestly the last few runs are almost unbelievable amounts of precip that would be the classic “too much all at once” scenario.
Euro model is also showing the storm and their last run has it dropping more precip than the GFS 😳
this is not the model agreement we are hoping for. let’s hope it fizzles out significantly. 1-2 feet would be fine.
SNOWW PLEASSSEE
I remember early December 2021 I was planning to load bikes for a trip to Mt Shasta and then Tahoe, and then a couple of weeks later the Bay Area was locked out of Tahoe for about 3 days in that big big storm. It can happen!