Monday, November 28, 2016

Why Does Mount Baker Get So Much Snow?

Mount Baker Ski area, located in the northern Washington Cascades (see map below), is a fabled


location for large amounts of snow.  For example, it holds the U.S. record for annual snowfall (1140 inches).


And today, the Mount Baker Ski Area website is claiming that they have more snow than any other ski facility in the entire U.S.!  With 83 inches at 5000 ft!


Are these Trumparian claims?  Is Mount Baker really that snow bound?  And if so, why are they so endowed with the white stuff?

A glance at the snow depth analysis from the NOAA National Hydrological Center shows that the greatest snow depths (darker blues and purples)  today are clearly over our part of the country,
A closer view shows heaviest snow around the volcanic peaks, the north Cascades and the Olympics.
The Hurricane Ridge ski area in the Olympics is not open yet, so I think that the Mount Baker ski area has reason to crow that they are tops in the U.S. right now.  And the all-time record was pronounced by an official arm of the U.S. government, so I am certainly not in a position to dispute their findings.


So what is it about Mount Baker ski area that gives it so much snow?  It is really not that high, with most of the ski runs between 4000 and 5000 ft.   Folks in Colorado or the Sierra would laugh at such low elevations.

But Mount Baker and much of the Cascades start with a big advantage:  lots of moisture and precipitation.  The western slopes and crests of the Northwest mountains are the wettest locations in the U.S. due to the persistent winter storms passing over the region in winter and the great enhancement by the regional terrain (see annual climatological precipitation maps below).

The north Cascades are not as wet as the western side of the Olympics, but are far enough to the northeast of the Olympics  that they escape much of the Olympic rain shadow. Furthermore, the terrain around Mount Baker extends more westward than the bulk of the nearby Cascades and has more of a NW-SE orientation, providing more uplift to the frequent southerly/southwesterly flow of the region.

Thus, with many incoming storms and moist air off the Pacific moving up the terrain (and thus cooling, saturating, and then precipitating), moisture is no problem.   The best supply in the U.S.

And there is not much high terrain upstream of Baker for the typical southwesterly winter flow;  there there is less competition for the incoming moisture.

But then there is the issue of temperature...the air must be cold enough to snow. That average freezing level (or melting level) of the air coming into our region (as observed at the Quillayute radiosonde site) is shown by the graphic below (from the wonderful NOAA/NWS Storm Prediction Center website).  On average, the freezing level is near 4000 ft.  And keep in mind that snow does not melt immediately at freezing...the snow level (where all the snow is melted) is about 1000 ft below the freezing (or melting) level.


So Baker is just high enough to get reliable snow.  And, of course, being in the northern part of Cascades makes it cooler than, say, central Oregon.

 But there is something else.   The amount of snow is enhanced for temperatures just below freezing, because the amount of moisture that air can hold (and thus precipitate) is greatest for warmest temperatures.   You can get heavier snowfalls in general for temperatures between 27 and 32F then 15 and 20F.    So Baker is at the perfect altitude range for maximum snow.  To put it another way, a ski are at 4000-5000 ft gets more snow than at 6000-7000 ft with an average 4000 ft freezing level.

Lots of moisture, great exposure to incoming flow, orographic/upslope precipitation enhancement, and perfect elevation range for the observed freezing level come to together for an optimum environment for lots of snow.

Finally, let's end this blog by looking at the snowfall and accumulation at  the Baker observing site maintained by the Northwest Avalanche Center.  The top figure shows 24h snowfall and the bottom,  snow depth.  About 65 inches at Baker, with the big dumps on Nov 24th and 25th.


More is coming.

16 comments:

Eric Blair said...

Wish I could ski there sometime, but it's not exactly close to where I live. And where do you stay overnight, Bellingham? Not quite as convenient as Whistler, to be sure.

David Riley said...

I suspect somewhere in Western BC or SE Alaska gets more snow than Mt. Baker. Plenty of available moisture (even more than Western Washington) and a relatively warm maritime airmass make that a virtual certainty. Alas, we will probably never know because those areas are too isolated to have regular snow measurements.

Chaz Bradworth said...

Science baby! World needs more of that!

MBeebe said...

Hi Cliff,

I see the long-range forecast is showing lowland snow for next Tuesday/Wednesday. Too far out to be certain yet, or is there a real chance of some snowy fun?

Darin Berdinka said...

Weather models routinely show a thick band of snowfall from Mt Baker (summit) trailing ENE towards Shuksan. I would think Baker's (ski area) somewhat unique snowfall patterns are driven largely by it's unique topography, and not it's elevation which is pretty standard. Sandwiched between two tall mountains (10.7k and 9.2k) and sitting directly above the rather large Skagit River basin to its SW it seems primed for lots of orographic enhancement.

As you point out temps at the ski area are rarely more than a few degrees below freezing. Warmer than average winters have proven that to devastating effect. Lacking any access to eastside cooling that Washington's other ski areas have I'd bet Baker is going to be the first casualty of climate change in our local ski industry. Bummer.

M. Hilberts said...

Is the shape and direction of the valley not the biggest driver for the " extra" snow (compared to other areas in the cascades)?
The valley starts wide and low and narrows and rises quickly providing what the germans would call a massive " staumauer". The subsequent orografic lift causes all the moisture to be "squeezed out" of the air ?

DaveRazz said...

Hello Cliff,
I am curious to know if this is also impacted by cold winds coming down the Fraser River Valley running into moist marine air? In other words, does that also create more snowy days than other locations in the NW?

Kevin said...

Hi Cliff,

One very localized aspect about the Mt Baker ski resort may also play a small part.

As you probably know, the ski hill is actually on Shuksan Arm, directly to the north east of the volcano. Most of the storms come from the southwest, meaning the precipitation goes around Baker before reaching the ski hill. The theory goes that, when the moisture has worked it's way around the mountain, it comes together again (kind of like a mini convergence zone pattern) and this rings out a tiny bit more precipitation due to the converging wind currents.

Anyway, that is the theory, in these parts :-).

P.S - it does look like next week will indeed be snowy in the lowlands - long overdue!

Jim Michon said...

They hold the world record for the most recorded snowfall inches of ANY North American ski resort. No area gets as much regular snow as Baker. They have the highest average snowfall and the record is 1,140 inches in '98-'99. Your 'suspect' areas are incorrect.

Bruce Kay said...

Is there anything to specific location, such as immediately windward of Mt Shuksan, the first major uplift on the western slopes of the main Cascade barrier?

Also, is there any convergence effect leeward of Mt Baker?

Thecatguy93 said...

Not a chance. Snoqualmie will be the first ski area to go, long before Baker. They have already been hurt by the changes we've seen, which are nothing compared to what's coming down the road. Baker has more snow than they know what to do with, and will for a long time.

Sysiphus said...

How can you know that? No one is out there measuring snowfall on a regular basis in the areas I am talking about. Unless someone actually does that, it is all just conjecture as to what is the real snowiest spot. Based on the fact that the areas in question have higher annual precipitation than W Washington and also have high mountains directly in the path of low pressure systems and the jet stream for even more of the year than the Cascades, I think this is something that warrants further study at a minimum.

Bruce Kay said...

Sisyphus - if you are talking about BC at all, there is plenty of observations, both snow pillow and precip and temps scattered all over the place. Just search BC Hydro and I'm sure you can get a good idea. No doubt the real snow zone is central BC coast and Alaska Panhandle.

ex libras said...

There are places closer to the mountain to stay than Bellingham. Check out the town of Glacier.

Radio Rahim said...

As far as actual ski areas in North America, I don't think that Baker has ever been exceeded. However, I live in Southeast Alaska (Juneau) and areas around here certainly can get more than that. This govt. site says the Juneau Icefield receives on average 100+ feet of snow annually: http://www.fs.usda.gov/detail/r10/specialplaces/?cid=fsbdev2_038753. To be fair, this hasn't occurred in the last few years and some of the Juneau Icefield Research Program staff I've talked to have said that the past 2 year's measurements have been some of the lowest on record. We have a ski area in town with a summit elevation of ~ 2600 ft. The record snowfall is around 600-700 inches which isn't nearly as much as Baker which makes sense due to the low elevation and maritime influence. Up in Yakutat, they receive even more precipitation than Juneau and they have higher mountains to boot; These areas receive Monsterous snow totals I assume.

Aloha said...

Not only does Baker get a ton of snow (the most snow!) they also get the lightest fluffiest of snow that I've experienced in the PNW including Whistler. Of course nothing will be as fluffy as the year I lived and skied in Steamboat Springs, Home of the Champagne Powder.

However Baker is pretty freaking awesome. Though not a large or fancy ski 'resort' compared to more well known ski areas, my every visit to Baker has been an epic ski day.