PINEAPPLE EXPRESS ??

New post on UnofficialAlpine.com

This One May Be The “Game Changer”

by Mark

Screen Shot 2014-02-05 at 7.09.38 PMIt’s hard to believe that there’s people out there that don’t know a big storm is headed our way for the weekend. Yet, we always manage to find people that just didn’t see the bold headlines and warnings from NOAA, the excited television news reporters standing by at Blue Canyon waiting for the first flake, or the tweets from SquAlpine announcing incoming powder. This storm looks like it could just be the “game changer”.

There’s no doubts amongst any forecaster that California is going to be in for the biggest storm we have seen in more than 13 months this weekend. The models keep showing more and more precipitation over the last few days. Unfortunately, you don’t have to be a true weather wizard to know that these huge storms are often powered by a “Pineapple Express” event. We first showed the evidence of that atmospheric river forming back on February 1st. The latest models today have pushed the jet just a bit farther south, increasing the expected total precipitation in Tahoe to around 9 inches of water content.

The downside is that these Pineapple Express events also bring us higher snow levels than we would like. How high you ask? Well that is the $1,000,000 question today. It all comes down to which model and which forecaster you believe. Last weekend’s storm really did not transpire quite the way any of the forecasters called it. The atmospheric river brought warm moisture to Tahoe that raised snow levels to about 10,000 feet at the start of the storm, which was very detrimental to lower base snowpacks. Fortunately, the snow levels dropped faster than expected, allowing a better recovery with more snow falling at the end of the storm.

Here’s a rough overview of what things look like as of today:

Thursday: Snow should mostly fall mid-day and snow levels will be low for this part of the storm. Accumulations of 5 to 10 inches are expected above 7,000 feet. Snow may fall as low as 4,000 feet.

Friday: Snow showers are expected to continue and there is a good possibility of some very strong winds on the east side of the Sierra. Temperatures remain cold for Friday.

Saturday: Snow levels will rise through the day as the warm moisture moves in. There is a strong possibility of exceptionally large crowds at Tahoe resorts for Saturday. Heavy rain and or snow is expected by late afternoon.

Sunday: Heavy rain or snow is expected for Sunday. The snow level is expected to be somewhere between 6,000 feet and 7,500 feet, depending on whether you believe the GFS, NAM, Euro or Canadian models. The Euro and Canadian models have been the champs in predicting these events lately and they are calling for the lower end of that range…at least today they are calling for that.

Monday: The colder air will arrive and drop snow levels back to lake level or lower.

The amounts of snow will vary widely, depending upon the movement of the snow level. In general, forecasters are calling for a total of 1-2 feet at lake level and up to 5 feet at the crest. That wide variation of amounts makes it clear that the snow levels may rise during this storm, but nobody is sure quite where they will land.

Here’s the total GFS forecast through Monday on the latest run. It has the least moisture of any of the models:

Screen Shot 2014-02-05 at 6.42.08 PM

The snow levels are going to be tough to forecast until it happens. We have covered this before. We hope to end up on the northern edge of that firehose, where it meets the cold front. Yesterday’s models put us on the warm southern edge. Today the models moved the cold front a bit farther south, which increased the amount of precipitation expected. Hopefully the operational forecasts will catch on to this tomorrow and show us some lower snow levels. If the front drops just a bit farther south, we may see just a bit less precipitation, but far more of it will fall as snow.

That said, this storm is totally a win for California. It won’t be a drought buster in itself, but it will be a significant drop in the bucket for sure. Will it be a win-win and also bring snow to the resorts and revitalize the local economy? We’ll have to keep an eye on that situation. Hopefully it’s going to be the “game changer” that gets us onto more terrain and more lifts…and not the “game changer” that leads ruts and puddles at the base of Alpine Meadows.

Leave a Reply

Your email address will not be published. Required fields are marked *