December 11, 2019

The Northwest Weather Machine Shifts Gears

You can tell something has changed.

A look at the latest wave vapor satellite image (which shows the amount of water vapor in the middle to upper troposphere) leaves one's mouth agape, with a HUGE plume of water vapor (light color) inundating the entire West Coast.   This doesn't look like the pineapple express, more like the pineapple train yard.


And looking at the radar image this afternoon, moderate precipitation, associated with an active front, is moving through the region.


Finally.   And more precipitation is on the way during the next week.

Let me show you the latest European Center Forecast.  Through 4 PM Thursday, the NW mountains will get up to a few inches.  But much less in the rainshadowed  lower elevations of western Oregon and Washington.


Through 4 AM Monday is below--now we are cooking (or whatever the wet terminology should be).  Up to 3-4 inches, particularly over SW Oregon and NW California.

But then the water gods get serious and the totals jump to 5-10 inches in favored terrain and absolutely nuts over Vancouver Island and coastal BC.

And now the a Christmas/Chanukah present for skiers.  The pattern will be both moist and sufficiently cold to get a good dump over the mountains... we are talking about the potential of a few feet.  I am getting more optimistic for lower-elevation ski area openings by Christmas

So why the change?  A major change in the upper atmospheric configuration.  The persistent ridge over the eastern Pacific will be generally replaced by a deep trough, with the ridge moving to the West Coast.  The map below, which shows the average upper level map (500 hPa, about 18,000 ft) for the next five days. The colors show the differences from normal (blue means lower than normal, troughing).  This pattern results in moist southwesterly flow approaching the West Coast.   Kind of El Nino-like.

A similar situation continues for another 5 days.  All these changes are happening just when we needed them.  Our rivers are generally below normal now and the snowpack over Washington is well below normal, with the Olympic Mountains at 13% (see below).   But California and the SW US is enjoying a great snowpack.


Enjoy the normal weather.



19 comments:

  1. Cliff
    In my 53 years around here, it seems mother nature ties to make up her deficits in her own good time. We humans just have a hard time waiting for her to do her thing.

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    1. like our moms would surprise us around a corner of a wall right?? mother nature is waiting for us to come thru with something then boom! she will pounce without warning and ruin this state watch man i feel like this winter will be huge!!

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  2. cliff i was checking until you posted a new vlog yay sounds good to me don't you think the lowlands will see snow anytime soon ??

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  3. Do the long-range forecasts foresee any sunny days before the end of the year? Thanks.

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  4. I just listened to your KVI interview with John Carlson, the second I've heard. I greatly appreciate your courage in taking a stand against the fear-mongering expressions of so many in this most ridiculous of debates, but I do have a question. Several years ago, I visited the NOAA site to learn what man's contribution to the greenhouse gas complement is. The figure listed for carbon dioxide was 0.117% with volcanic and other natural causes accounting for the remaining 99.883%. I have no problem with new technologies creating a cleaner world, but I fail to see how "sucking carbon out of the atmosphere" will either stem the tide of natural climate change, given how little we humans apparently contribute, or even be a wise move if we begin impacting natural contributions, given the photosynthetic needs of plants in their growth, the oxygen they provide we mammals through that process, and therefore the potential of impacting the planet's delicate food chain. Some of our past technological "advances" haven't turned out to be all that beneficial. I'll monitor your blog for any comments you may have in this regard. Thanks.

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    Replies
    1. While techincally accurate, our output is in additional and man's emission of CO2 dwarf that of volcanoes.
      The facts are easy to find:
      https://skepticalscience.com/human-co2-smaller-than-natural-emissions.htm

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  5. We had a thunderstorm early this morning on the Kitsap Peninsula. It was satisfying after the lack of rain. Does anyone know what's with what looks like small thunder cells north of Bellingham around Abbotsford on the KOMO radar? They're there most of the time. Are there as actually constant patches of heavy rain or is the radar not accurate up there?

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  6. I would be curious to compare the chart above with low/high pressure (which shows an El Nino-like pattern) with one that shows a typical La Nina-like pattern. Just for comparison. Thanks!

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  7. We flew from Kona HI yesterday and the flight was 1 hour faster than scheduled due to the express train!

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  8. People love to make a big deal out of weather. In the big picture, the difference between snow covered Cascades in late November vs mid December is nothing.

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    1. But in terms of seasonal snowpack, December storms are important. And the huge snowstorm predicted for this week? Currently it is fizzling. It is raining lightly right now on Stevens Pass. We'll get some more snow out of this weather system, but yesterday's forecast has been revised way downward. When we don't get much snow in December, we often (though not always) have to wait until late February-early March for big storms. So...we'll see.

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    2. I agree, been on the Mt. Hood ski patrol for 53 years and I've seen the ups and downs of the cascade snow pack and this year isn't that unusual so far.

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    3. SD of mean monthly snowfall from November through March at Mt. Baker Ski Area ('05-'06 thru '18-'19) is only 16". Mean total Nov-Mar snowfall for this period is 617".

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  9. I'm glad you are monitoring everything, Cliff! I look to you for the facts.

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    Replies
    1. No, it is the National Weather Service (4,000 employees) and its thousands of volunteers who monitor everything.

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  10. Was good to finally get this soaker in Kitsap. We really needed it after the constant rain shadow. The track has already realigned to a due West to East flow so its beck to being in the sunny doughnut hole. Throw the forecast out again for another two weeks. We are going dry yet again, haha! Can always go to Sequim to see rain.

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  11. January and February are expected to be mild across the Southwest and South.
    Cooler than average conditions are likely in the Upper Midwest.
    Water temperatures in the Pacific will play an important role in winter temperatures.
    Colder than average air is expected to remain place across the northern tier of the U.S. through the end of meteorological winter, while the South and Southwest are likely to see a mild winter, according to the latest outlook from The Weather Company, an IBM Business.

    Throughout the first three months of the year, temperatures are more likely to be above than below average across the Southwest into Texas. The Upper Midwest will likely see below average temperatures.


    (MAPS: 10-Day Forecast)

    Here's the outlook month-by-month:

    January
    If you're looking for a winter getaway, head down to California and Arizona for much above average warmth, by winter standards. Typical winter highs are already in the 50s and 60s in those states.

    Near average temperatures are expected from the Pacific Northwest through the Central Plains and into Southeast.

    The most likely spot for cooler temperatures compared to average will be from the northern Plains into the Upper Midwest. Highs there are usually in the teens and 20s to start the year.


    January 2020 temperature outlook from The Weather Company, an IBM Business.
    February
    Temperatures going into February are expected to be well below average for a large swath of the Midwest and Plains.

    Far-below-average temperatures are likely in those regions, with below-average temperatures also reaching into the northern Rockies. February is normally the coldest month of the year in many of these areas, but the outlook calls for even colder weather than usual.

    Milder than average conditions are likely from southern California to much of Texas.

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  12. Nice, steady rain here in Ashland since early this morning. This is welcome after the dry October and November. The clouds parted over Grizzly Peak (elev. 5,922') a bit ago and I could see fresh snow.

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