Friday, February 26, 2016

The Slowly Fading (But Near Normal) Snowpack



As skiers can tell you, the region's snowpack is slowly fading under the onslaught of warmer than normal temperatures.  Here is the latest snowpack status based on the SNOTEL observations.  A range from 89 to 128% of normal for the water content of the snow.  Unfortunately, with warmer temperatures and rain on the snow, coupled with inevitable settling, much of the snowpack has degraded into the familiar Cascade concrete, in contract to the wonderful powder earlier in the season.



But we are a lot better off than last year.  Here are maps of the water content of our snowpack last year and this year on February 25th.  Big difference, with more snow this year.  And this year there has been WAY more total precipitation (including a lot of warm rain) that has filled our reservoirs.

Let's look at few at Stampede Pass (3850 ft) in the central WA Cascades and the far higher (5130 ft) Paradise Ranger Station near Mt. Rainier.  A similar story at both for cumulative snowpack and precipitation.  A huge surge in snowpack in December followed by a slow rise afterward.  The observed amounts (blue lines) tracking near normal (red).  Total precipitation (black line) well above normal (gray line).  You notice that snowpack normally peaks in early April.  This may not be true this year due to the expected warmer than normal El Nino conditions.


The next 72h will bring precipitation (today Friday and on Sunday), but conditions will be warm, so expect snow mainly at higher elevations (particularly about 5000 ft).  Here are the predicted totals.  The higher terrain in the British Columbia mountains do best.

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13 comments:

Unknown said...

Hello Dr. Mass. I've enjoyed reading your blog over the years and I have learned much, however, it appears that you are not an alpine skier and I wanted to take a moment to correct of few things that you have said over the years regarding such. First, "Cascade Cement" refers to the fresh, wet and heavy "powder" we are frequently blessed with when the snow come down at around 30 degrees or higher. It has the apparent consistency of wet cement. The snowpack does not "degrade" to cascade cement, it comes down as cascade cement. In the spring, with the freeze thaw cycle, the snowpack will change from rock hard in the morning to fun, workable slush in the afternoon, maybe even corn snow under the right conditions. But it will not degrade to "cascade cement." With the longer daylight hours, spring skiing is actually quite fun around here. Also, you have in the past, referred to Mt. Baker as a "higher elevation" ski area. While that ski area does have a high latitude compared to others in the state, the altitude is not remarkably high at all, in fact it falls on the lower end of the scale compared to other ski areas in the state.

Tim said...

Interesting to see that precipitation is quite a bit above normal but the snow water equivalent and accumulated snowpack is about normal. Obviously it is the warmer than normal conditions that are responsible for this otherwise the snowpack would be much deeper and snow water equivalent much higher to match the accumulated precipitation. More precipitation is then falling as rain and/or more melting is happening. Is this what we can expect with a warming climate in the Pac NW?

John Bove said...

Dr. Mass, am I reading the Snotel charts correctly that Stampede has about 2.5' of show on the ground currently and Paradise about 5'? Thanks.

Donald Strong said...

Cliff: I am worried that you have not told us lately that global warming isn't happening yet.

Unknown said...

Cliff, what is the upcoming predicted "NILE OF ATMOSPHERIC RIVERS" going to do to the snow pack next week?

http://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=pmdepd

JeffB said...

Cliff, less than 5 days before this post, I skiied in 10" of fresh powder at White Pass last Saturday. And then great packed powder with some stashes of fresh powder still to be found last Sunday. You clearly need to get up to the resorts! There have been some wet days, but a lot of powder days too.

Rebecca Timson said...

Thanks for the accurate info, Cliff. Local snow jargon aside, with warm February weather the snow depth has been hard hit and powder is a last-week thing. Things can change fast at altitude. But if you like spring skiing, it has been a great week on the slopes above 4,000 ft.

Matt Thompson said...

Cliff, first can you respond more? Second, can you block all the trolls constantly quoting their ignorance about the issue of climate change, so called deniers? They add nothing to the discussion, not one thing, except maybe to display their massive stupidity, lack of original thoughts, or the ability to actually form a coherent and logical thought that Fox News didn't plant in their brains?

Unknown said...

Meanwhile, mother nature delivers once again, a foot of powder at Baker on Sunday night with a base now over 170 inches!

David B. said...

Don't be mislead by the statistics for the Rocky Mountains. Denver for example has little actual spring weather. The temperature just lurches between almost summerlike and almost wintry (which we would consider flat-out wintry by our standards). I lived in the Rockies (first northern New Mexico, then northern Utah) as a teen, and more than once had experiences of a sunny afternoon in the mid or even upper seventies being followed by a snowstorm with highs in the thirties the next day. Such wintry storms could happen surprisingly late into the season (May in northern New Mexico, June in the northern Utah.)

The transition was a period of very blustery weather, often with dust storms. Usually it would take a day or two, but sometimes as mentioned above it would happen overnight. Bottom line is that spring is often not a very pleasant season. When I moved to the Northwest decades ago, it was a real treat to be someplace where springtime is a major season in its own right, with relatively steady and moderate temperatures and weather patterns.

David B. said...

@ Donald Strong -- I cannot remember Cliff ever denying that global warming is happening. What he has denied (multiple times) is that global warming is the cause of this or that particular present-day extreme weather event. A subtle difference perhaps but a significant one.

iamlucky13 said...

"I cannot remember Cliff ever denying that global warming is happening. What he has denied (multiple times) is that global warming is the cause of this or that particular present-day extreme weather event."

Yep. I've noticed this infuriates quite a few people, and they develop vendetta's when told that a 3/4 of a degree rise in global average temperatures over 150 years is not as easy to observe as they insist it must be. From time to time, I come across people labeling Mr. Mass as a climate change denier as a result.

In particular, I raised a discussion elsewhere about his arguments that the recent "blob" was not consistent with long term climate forecasts for our region, and instead seemed to be a particularly unusual natural variation. Nowhere did he argue or even imply that meant climate change was not happening, just that the blob was not evidence of the effects of climate change. That proved it to the others in that conversation: Cliff Mass was a climate change denier seeking to muddy the perfectly clear waters of science.

sunsnow12 said...

John Bove - Paradise currently has about 10 ft of snow on the ground and Stampede Pass has about 5.5 ft. SWE is the amount of water, in inches, that the snow holds; so in the case of Paradise, that's about 60 inches of water. Hope that helps.

Stampede Pass - http://www.nwrfc.noaa.gov/snow/snowplot.cgi?SMPW1 - snow depth 67"

Paradise - http://www.nwrfc.noaa.gov/snow/snowplot.cgi?AFSW1 (see graphs downpage for snow depth) - snow depth 120"