“Too Much Snow” (With More On The Way!)

A few weeks ago we discussed the potential for a stalled upper level low pressure system to park over the Western US, resulting in a long duration snow event for nearly all of the Western US. Several storms have rounded this upper level featuring bringing wave after wave of snow, leading to massive snow totals in the Sierra, substantial totals in Washington, Oregon, and Colorado, and respectable totals elsewhere. Finally, the last wave of this storm is coming onshore this evening, with another major thump of snow, cold temperatures, and strong winds. The upper level system will finally progress eastward, but not before it stalls one last time, and ejects a closed low to the southwest. This will serve to prolong the already lengthy snowfall event a few more additional days. After the parent storm and the bebe move east, the pattern should remain active through the start of the new year. Check out the progression of the upper level pattern below:

Once again, the Sierra will get clobbered. Resorts have been measuring totals in feet before this last wave, and they will be doing so once again later tomorrow when the snow winds down. Another 1-2 feet fell last night, on resorts that were all closed except for Diamond Peak. We got some deep turns at Diamond today after learning Palisades was closed for the day. Quick edit from Diamond. Wind will crank tonight, as they have much of the last few days, leading to some wind affected snow and lift delays. I-80 has been closed for over a day and there is now estimated opening time. Tahoe is a hot mess right now. Have you ever seen snow before, or is this the holiday crowds? Tahoe is shut down again today, even Diamond Peak. I guess Heavenly has some stuff open but getting there from the west side of the lake is rough right now. We have reached the ‘too much snow’ status. Usually we avoid the big Tahoe storms, with insane snow and huge winds, but we gambled on this one, and so far, have lost. Try again tomorrow.

Here is a snowfall map from today into tomorrow.

The Cascades of Oregon will get another solid dump as well.  10-20” with higher amounts as you head south.

The moisture will stream inland, targeting Arizona, Wyoming, and Utah next. Another 10-20” is possible in Northern Utah from Monday to Tuesday. The snow quality should be better this time around as winds won’t be blowing over small structures.

Wyoming has seen a steady stream of moisture lately, finally allowing the base depths of Targhee and Jackson to reach respectable levels. This next wave will continue to add to these totals, with another 9-14” by the end of the day Tuesday.

The recent snow at Arizona Snowbowl had enable them to open much more terrain, and that’s great with another 12-18” inbound. This is a cold storm, with low snow levels, and some strong winds too, from Monday night to Tuesday night. The aforementioned ejecting closed low will add another foot or so to those totals through Thursday.

Colorado will continue to get heavy snow too, especially those areas favored with southwest winds (Wolf Creek, Silverton, Crested Butte, Aspen to name a few). How are they even keeping track of snow at Wolf Creek and Silverton at this point? Throw another 1-2 feet their way, with the higher totals at Wolfie. Tuesday and Wednesday look like good times to be at Wolf Creek. 12-18 more for Crested Butte and the Aspen resorts, with CB likely on the high end of those totals.

New Mexico will get in on the action as well. Solid 4-8” snowfalls can be expected both Monday and Tuesday nights at Taos. Ski Santa Fe and Angel Fire will get some decent snow during this period as well, with Wednesday AM looking best for Santa Fe.

A lot if you may be wondering why there is all this snow in the central and southern parts of the West during a La Niña, while Montana has been a little bit left out. If you look at all the La Niña years that produce the typical average anomaly maps posted in seasonal forecasts (shown below), a few things stand out. First is the limited number of La Niña years used to produce the precipitation anomaly figures. Second, you can see that during several of these La Niña Winters, places like Tahoe and Colorado saw above average precipitation. Some La Ninas were even very below normal in the Pacific Northwest. The bottom line is that these seasonal precipitation anomaly maps are just averages, thus any given winter can depart from that average, sometimes substantially, and especially during La Niña, because the sample size, compared to the number of El Niño winters on record, is much smaller.

While warm temperatures and winds have wreaked havoc on this seemingly wonderful weather pattern, we are glad to see resorts catch up to and even surpass average to date snowfall. Most of the West is now setup with a great base to lay the foundation for chasing the rest of the season, starting tomorrow. Look at the SWE % to date:

Nearly all of the West is at or above normal. So we can at least be happy about that.