December 23, 2015

Snoqualmie Pass is Buried in Snow

Last year, Snoqualmie Pass had very little snow and the ski areas remained shut for most of the winter.


This year Snoqualmie is being BURIED IN SNOW.

Every day at 6 AM, Washington Department of Transportation measures snow depth in the pass.  Here are the latest numbers.    26 inches of snow between 6 AM Monday and 6 AM Tuesday, with 85 inches on the ground.  An increase of 50 inches in 5 days.  To quote Darth Vader:   Impressive, Most Impressive.


The Wednesday report shows another 11 inches of new snow, but compaction resulted in only a 1 inch increase in depth.

The pass has been closed several times during the past few days, with chains often required.  So far this year over 12 feet of snow has fallen in Snoqualmie, eclipsing the total snowfall of the entire last year.

But it is not over.   Last night, another frontal system moved through, bringing a surge of heavy snow.   Here is the forecast of 72-hour snow total for the region (a circle indicates the location of Snoqualmie Pass).  Another 2-3 feet!


The freezing level is quite low now and during the next few days, with the associated snow level dipping to around 1000 ft, with mixed snow getting down to 500-1000 ft at times.   Don't be surprised to see a few flakes at sea level, particularly over NW Washington.


But why so much snow?  The reason is that the atmospheric has been stuck in a configuration that has been ideal for central Cascade snow (and very favorable for heavy rain over Oregon).   Here is the upper level (500 hPa) forecast for Tuesday at 7 PM.  The lines are height (like pressure) and winds are strongest when the lines are close together (that is where the jet stream is located).   The jet stream is oriented NW-SE with the axis crossing Oregon and northern CA.  We are on the north (cold) side of the jet stream and there is a trough just offshore.

So we are cool, with disturbances rippling along the northern side of the jet stream.  Good for Cascade snow.


18 comments:

  1. The same can be said about much of Eastern Washington.Spokane has already exceeded last winter's snowfall total,with more than 17 inches in the last week alone.The snow depth is close to a foot citywide.Especially heavy snow in the Idaho panhandle due to upsloping winds.

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  2. Downpour in Sequim this AM at 37F - must be loading in the mountains.

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  3. Hey Cliff, what's the snoqualmie pass forecast for tomorrow? We are driving over the pass in the morning. We have an AWD car and will be stocked up with food/water/blankets for the trip in case we get stuck for avalanche control, etc.

    Figures, I've had snow tires on my car the last 3 or 4 winters and we always miss the snow when traveling over the pass. Finally changed to all-season and then....have to drive through snow. :)

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    1. Well, now you know. Snoqualmie pass closed all day. North Bend to Ellensburg, both ways. Given my location in Roslyn (at leat 30" so far this month) I'm looking at flight schedules from eastern alternatives like Yakima or Tri-cities. But I couldn't even do that today, all the routes out of here are closed.

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  4. Accuweather is calling for lowland snow in Seattle/Bellevue on Christmas Day. Happy rumor, or nonsense? The kids want to know but I said I won't believe it until you say it. :)

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  5. Argh, even on your blog I can't escape Star Wars!!

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  6. You bet, Cliff. It is nice to see Snoqualmie Pass get hammered.

    When the surveyors in the mid 1800s went looking for a railway route across the Cascades they probably encountered the same snowpack...they probably chose Stampede Pass for the Northern Pacific Railway because the snow on Snoqualmie scared the heck out of them...even though Snoqualmie Pass is ***generally*** an easier crossing.

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  7. Very good little in-service Cliff. It has been amazing watching the satellite and radar loops this last 24 hours. Thanks

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  8. @Alan Majchrowicz, resign to it yourself you shall.

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  9. Come on Cliff! Talk to us about low land snow! We're swing to know what you think if the forecast.

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  10. Hey Cliff, Merry Christmas, your blog is truly awesome, from a long-time reader.

    Dave

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  11. Sometimes I wonder if folks read the blog before commenting. Quite often the answer is right there. Also wondering how people think Cliff can give individually pinpointed forecast for their current plans. Amazing. Have a good holiday season, Cliff, and thanks for your patience.

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  12. Can you PLEASE bring the snowpack to the Sierra Nevadas? The poor Devils in California need it!

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  13. NWS says 40% chance of snow Christmas Eve / Christmas! Would love to hear Cliff's read on it!

    And Merry Christmas / Happy New Year Cliff - your blog is the RADest.

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  14. A more typical El Nino split flow pattern is looking more likely to develop next week, right on time. Meanwhile, temperatures spike over the east coast. Weather Underground provides the following write-up.

    Off-the-charts record warmth for Christmas
    The well-advertised holiday warm wave continues to astound, with “instant” record highs set overnight in many locations from the Great Lakes to the Northeast. Readings at midday Friday were already into the 70s Fahrenheit from southeast New York to the Gulf Coast, with widespread 80s across Florida. Some of the daily record highs along and near the East Coast on Thursday will be 10°F or more beyond the warmest Christmas Eve in more than a century of recordkeeping. Breaking a longstanding daily record by more than 10°F is noteworthy in itself, and the intense zone of high pressure off the southeast U.S. coast is uncannily similar to the Bermuda highs common in midsummer! Given the intense interest in holiday weather and the many family gatherings under way, we can expect this bizarre weekend to spur countless dinner-table conversations about climate change and “global weirding.” A warm wave like this doesn’t “prove” climate change; it is one manifestation of the weather that results from natural variations such as El NiƱo playing out in a global atmosphere that is being warmed, moistened, and shifted by ever-increasing amounts of greenhouse gases. Like the spectacular warm wave of March 2012, which brought 90°F readings to Michigan, the tropical Christmas Eve 2015 could serve as an excellent candidate for attribution research--the attempt to unravel how much long-term climate change raises the odds of a particular weather event.
    http://www.wunderground.com/blog/JeffMasters/tornadoes-rake-mississippi-delta-more-storminess-ahead

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  15. Merry Christmas Cliff! Thank you for your knowledge and expertise and the common sense approach! Your blog is where I go to for weather and climate info.

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  16. I drive over Snoqualmie every month and usually twice in December. I decided to skip the second December trip this week after reading the NWS forecasts of foot a day. Results were even more impressive. Grateful to be home for Christmas. Merry Christmas Cliff and thanks for the blog.

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  17. thank you so much for share with us this infos
    ArganOilhome

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