A Shifty Forecast

And yet again, it was one of those days that turned out to be better than expected at Alpine Meadows. The remote sensors at the base of Roundhouse only showed one inch of new snow overnight. The marketing blast via the app said that 0-3 inches of snow had fallen. That put me on a quest to find those “3 inch” locations this morning. Over the next two days, we should see significantly more snow, but we also get winds that may limit our ability to utilize that snow. I’ll do my best to break down the shifty forecast below.

We started the day on the Summit chair, drawn there by the frosted trees un the upper part of the mountain calling like a siren. Sunspot looked attractive, with its corduroy from an early grooming being well hidden by new snowfall. Looks were deceiving as the underlaying corduroy was too firm under not quite enough new snow. Then there were the frozen cauliflower pieces randomly frozen to the surface that called for extreme caution. For my second run, I moved 50 yards south to Tower 19, where the ratio of soft new snow to frozen surface was significantly better. Keep in mind that the photo above was shot at 9:08 and by 9:30 this zone was completely schralped.

As per usual, we set out to find those places that got less traffic and less sun yesterday afternoon, leading to a smoother underlaying surface. By the old way of thinking, that would lead you to a hike out High Traverse. On my third departure from the Summit chair, I counted 338 people climbing the cat track to Upper Saddle. Okay, that was an exaggeration, but High Traverse laps used to be a place of solitude. It’s not that way any more. Then there was that big ball of fire, cooking the small amount of new powder at a rate that exceeds my climbing speed.

The good places today were the ones that were north facing with tree cover to protect the snow from the sun’s heat. That narrows choices quite a bit, so once we found a zone that was skiing mostly good we stuck with it and did not go out in search of better snow. It certainly was not an epic powder day, but most of my runs were 80% good turns with the other 20% being quite scratchy. Theoretically, tomorrow and Monday should be substantially better, depending on which chairs open due to the expected high winds, and whether or not the forecast totals even come close. Powder fevered crowds will likely be an issue tomorrow and probably Monday too.

That Shifty Forecast Explained

shift·y /ˈSHiftē/ 1. appearing deceitful or evasive.

The models have been absolutely shifty this week in that there has been very little model agreement run to run, or in comparing the different model runs. That means the forecast has been evolving rapidly, and you have to work hard to keep up with those changes. I had to laugh yesterday as a very popular ski blog breathlessly reported a “huge Atmospheric River event” for Tahoe later this week. Unfortunately they posted that well after most of the major models had pronounced the AR event dead in the water. Then again, because it was Andy’s day to post yesterday, I did not get a chance to tell you to forget about that third storm.

What that means is that most of the snowfall has “shifted” into the beginning of the week. The snow moves in late tonight and tomorrow, then really ramps up Sunday night into Monday. That is where the model agreement ends. Because I have been using the mostly level headed GEFS “ensemble” models most of the season, let’s start with that. Here’s the sounding for the top of Alpine Bowl by Friday (mostly by Tuesday):

Those numbers are about in alignment with the Reno NOAA Winter Storm Warning calling for 1-2 feet by Tuesday. But in comparison here is the same sounding point for the same time period for the CMCE model:

That’s significantly more snowfall, which is likely the basis for the Sacramento NOAA office to up the totals in their Winter Storm Warning, calling for 1-4 feet. The commonality is that they both put the minimum at 1 foot.

There’s also significant variability in calling snow levels. The Reno office is calling for a mixed rain and snow event for Sunday, with snow levels rising to about 6500-7000 feet midday tomorrow before dropping again. The Sacramento office shows snow levels closer to 5500 feet. Then there’s the winds. The Sacramento office only calls for winds to 55mph. The Reno office calls for ridge winds at 100+mph, which seems to have become the norm. That would lead to multiple lift closures, hopefully the shiny boxes.

Why the shifty models? We have not really had much in the way of normal Gulf of Alaska storms this season. This week looked like we might see something more “usual”. Instead, the incoming lows are just riding over the top of that Baja Ridge which as pushed storms northward all season. It’s a bummer that it’s not a huge winter, but at least in Northern California we are hanging in there with close to normal precipitation, keeping our reservoirs full and tamping down fire danger. Hopefully I will have the month end figures for you in my next post.

See you out there tomorrow…