Doubling Down On Winter Storms

I went skiing this morning. There was excellent spring skiing.

TL;DR None of that matters.

Let’s look a week ahead into the forecast, as everything we have been skiing today, yesterday and the past week is about to go through some change. Tomorrow, nor any of the next ten days will be about spring conditions or corn snow. We are headed back into winter for at least the next ten days. The doubling down on storms means that we have two good sized storms in the pipeline, lasting into next Wednesday and potentially beyond.

I mentioned in my last report that the potential for snow totals had been trimmed down by about 10-20%. There were times when it looked like we could see 50+ inches of snow out of the first storm by itself. Now it looks like we could see about 50 inches of snow between the two storms. That’s probably a better solution. Probably somewhere around 2% of the ski population is equipped and prepared to ski 4+ feet of snow. Truth be told, most of the current ski population at Alpine Meadows has trouble skiing in 6 inches of new snow. Too much snow at once increases risks for avalanche and requires more digging out on the mountain. So one regular sized storm plus a followup medium size storm is a good thing.

Storm Number One: Late Tonight Into Thursday

It’s pretty official now as that Winter Storm Watch has now become a Winter Storm Warning. The Sacramento and Reno office of NOAA have somewhat different details and the one from Reno is a bit more foreboding:

So yay, 2-3 feet of snow possible sounds great and I have already heard people talking about taking off days for “powder fever”. But if those sorts of winds materialize, that is going to be really problematic for lift operations. That is almost certain to put everything on a wind hold except for scattered lower lifts. It’s not just the ridges winds, the high winds at lake level mean that even the lower lifts could be affected. New snow that does fall will almost certainly be wind affected. What that means in particular is that the snow will get packed dense and heavy. Wind loading and avalanche danger will also be elevated, which means slower openings.

Those strong winds also mean white out conditions and snow drifting on roads. There’s also a reasonable possibility of power outages, something we have already experienced at Alpine Meadows this year.

Here’s the total snowfall through Thursday night according to the last complete run of the GEFS.

If you’re wondering about snow levels, this event does look like all snow at this time…but we have been burned several times this season snow levels that fall slower than expected. The heaviest snowfall is not expected until Wednesday afternoon into Wednesday night.

Bryan Allegretto at Open Snow was actually the voice of reason this morning on Xitter. He addresses the possibility of starting with higher snow levels, resulting in somewhat less snow overall. Don’t say you were not warned:

Wednesday Afternoon Update: As we have grown accustomed to this season, the storm is coming in later than expected and a bit warmer. It’s partly cloudy and 38 in Truckee right now. The forecast indicates we should still hit forecast totals by Thursday night. Also, Storm 1.5 rolls through Friday dropping up to 6 inches of snow.

Storm Number Two: (Sunday?) Monday Into Tuesday

A second storm is out there in the Pacific. I mentioned this a week ago, then it disappeared from the models and now it’s back. Yesterday it looked bigger than storm number one and today it looks weaker than storm number one. We are outside of the five day window of believability on this one, so the details are fuzzy when it comes to timing and snow levels. In one of several Xeets from BA today, he feels like the timing will be pushed back into Monday for this storm. That’s important as people want to know whether or not they can make it home if they ski Sunday. The safe bet would be to leave earlier on Sunday rather than later, unless you think BA is correct. Once NOAA releases a Winter Storm Watch for that storm, you may get a better idea on timing.

The models are a little bit better at discerning possible snowfall at 6 days out. Before you get all excited looking at the model below, this is the total forecast between now and next Wednesday. It includes the 28″ of snow from storm number one. So looking at the sounding for the top of Summit at Alpine Meadows showing 49 inches, you need to subtract 28 inches. That would result in about 21 inches of snowfall expected from the second storm at this time. That said, with a short lived ridge over the weekend and some warmth and high angle sun, we won’t have a snowpack that is actually 49 inches deeper.

As of today, there is another potential system out there for the following weekend. Right at this minute it looks like the Baja ridge begins to recover and that system turns into an inside slider.

TL;DR We have two systems bringing large amounts of snow over the next week. Snow will also be accompanied by high winds that may affect the density of the powder. There are potentially impacts to lift operations, road conditions and power outages. Nobody can tell you when to leave on Sunday.

It’s Andy Wertheim’s birthday tomorrow. If you see him, take a minute to say “You’re THE Andy!” and wish him a happy birthday.