Tuesday, December 16, 2014

How the Grinch Stole Northwest's Christmas Snow

We are now getting close enough to the holiday season to make an unfortunate forecast:  there probably will not be enough snow for Cascade mountain skiing during this holiday season in WA and OR.   As we will see, a major grinch will be a strong atmospheric river that will develop next week.

We start with a very poor snowpack in place.  Here is the % of normal snow water equivalent (SWE) in the western U.S. mountains. The western Cascade slopes are now 15-20% of normal.  The Olympics are 23%.  A bit better in the north Cascades and the eastern slopes, but still considerably below normal. With the recent precipitation, the California Sierra are doing much better....a nice turn of luck for them!

The NW Avalanche Center summarized the snow situation (snow depths) at some major ski areas (see below).  Mount Baker is 9% of normal, White Pass has NO SNOW,  Crystal has 6%, and Stevens has 25%.  We are way worse off than last year, which was not a good year.  6 out of the 11 sites have ALL TIME RECORD minimum snow for Dec. 15th.



So we start off with a sparse snowpack.  Next week a major ridge of high pressure builds over the West Coast.   Here is temperature anomaly (difference from normal) for the NCEP ensemble mean at 850 mb (around 5000 ft) for Monday December 21st at 4 PM.   Warmer than normal (orange colors).


The Climate Prediction Center (CPC)'s 6-10 day forecast for December 22-26th continues the trend with warmer than normal in the west.




A major issue is that a major atmospheric river will form over the weekend.  Warm, moist, air with heavy rain over Northwest mountains.  Here is the vertically integrated water vapor content prediction for Saturday at 10 PM.  Very juicy (red and white indicates the highest values).  There will be more flooding...guaranteed...bad for snowpack.


What about snow this week?  Let me snow you the UW WRF model totals for the next two 72 hour blocks.   First, 72h hours, perhaps 3-6 inches in the WA Cascades.


Next 72 hour, up to a foot in the north Cascades, but not much south of Snoqualmie.  Much more in the mountains of SW BC.   Whistler will be in better shape,


The trouble is that we won't get that much snow this week and then that snow will be hit hard by the heavy rain and warm temperatures.  Sorry.

12 comments:

Sysiphus said...

Looks like there is a good chance of shifting to a cooler regime late next week. But, will there be moisture?

Rod said...

The good thing is, even warmer water will fill the reservoirs...just hope for a late arriving snowpack which is not unusual in these parts.

Snow skiing at Christmas is the least of the worries.

snapflux said...

Rod, keep in mind that snow is a reservoir. Man-made, dammed up lakes hold a lot less water than the snow does. We're not in a water crises in the PNW, but we will be if we don't have the snow to provide a release of water during the drier times of the year.

JewelyaZ said...

It looks like we won't have drought next summer IF we get late-season snow like we did last year. And I know California's still in the desert, relatively speaking, but they must be pleased to be getting so much more rain and snow.

CascadesOldTimer said...

Hey Cliff Boy,( I can say that because I've been working in the Cascade mountains for 50 years.) I'll bet you a lift ticket and lunch at one of our lodges that Baker will have 25"on the base at 4500' and be open by tues or wed. Duncan GM

Larry Scrivanich said...

Cliff, I will double Duncan's bet, 2 lift tickets and 2 lunches, but we are already open, top to bottom, 2200 ft of vertical with great skiing. I enjoy your blog but before you post that we are closed call us, there will be awesome skiing in the Washington Cascades during Christmas break. Larry, Owner, Mission Ridge Ski and Board Resort.

NOPE said...

Go, Mt. Baker!
Boo, Cliff Mass!

Recurrence said...

Looks like Whistler is getting 24 inches in the next few days.

From Seattle, It's only a few more hours drive than Stevens Pass is and the CDN dollar is down. Might as well head up there for the weekend :)

John Marshall said...

No weather forecast is more predictable than the snow forecasts from ski area owners and operators just before the Christmas holiday.

faronium said...

maybe a post about a potential white Christmas in the lowlands is needed!? There are some early indications for a snow event.

David B. said...

faronium: It's unlikely. The models that are showing cold air coming show it coming right after Christmas Day.

Joe Catellani said...

don't blame the messenger!