December 13, 2008

Major Cold

The winds have subsided now as the strong low has moved east. There are a lot of lessons regarding that low and intense winds it produced...not the least, it being a good example of the difficulty of forecasting rapidly developing systems over the oceans. On one hand, the computer models were extraordinary...predicting the rapid development of an intense low from nothing, days in advance. The problem was the track...and keep in mind that we were only talking about a 100 mile error of the models a day before. Meteorologists do better than least we saw it coming! The low brought max 40-60 mph gusts in the interior and some gusts to 80-90 mph on the coast. There was some light snow last night at higher interior elevations...but nothing serious. And a key issue is that the road surfaces are relatively warm since our air temps have been fairly warm. This protection will be gone in a few days.
The big...and serious is the cold. We are about to go into the most significant cold spell in years, and you should prepare for it. Remove hoses from exterior pipes, wrap vulnerable pipes, leave water dripping in vulnerable know what I am talking about.
Today, we have some residual moisture from the storm, but will progressively dry during the day (see radar image). The air is fairly warm right now, with onshore flow from the ocean. The freezing level is about 2000 ft over Puget Sound, snow level about 1000 ft. Today the cold air will start to move in...and particularly tonight. We will get into the mid and upper 30s today, but tonight temps will drop in the 20s. Cool air will start to push into the Fraser RIver valley and strong outflow will begin..with NE winds moving SE over Bellingham, over the San Juans and then will hit the Olympics. This can produce upslope flow and snow on the NE side of the those near Sequim and Port Angeles should prepare for it. I have inserted a series of model output below showing sea level pressure and low level can see the cold pushing in. Note also that even colder air will be east of the week they will have HIGHS in the single digits and subzero minima. A large pressure difference will develop across the Cascades (due to the colder, denser air east of the crest)...and this will produce strong easterly winds in the Columbia Gorge. I love how everything happens at once in these intense weather periods.
What about snow in the lowlands? By later today the air will be cool enough for snow almost everywhere...but it will be generally dry..a disappointment for the kids. A disturbance from the north will increase the chances of clouds and precip (snow) tonight...BUT by that time there will be a strong easterly, downslope component off the Cascades. I suspect the result will be little, if any snow, east of the Sound and light snow (0-3 inches) on the western side and over the Olympic Peninsula.
Then we settle down to an extended cold period that could last a week. There is a possibility of light snow midweek...but lets wait to talk about that.

PS: Several has asked me about getting the book in times of the holidays....particularly since amazon and are temp out. Several local bookstores have lots of books...including university book store...and several, like UBS, ship...just like amazon. A number of barnes and noble locations have books. 5000 more books were printed in the past week...and should be getting into the system by the end of next week. Anway, check my web page (click on book icon) to get more info on availablility issues.


  1. Cliff,

    You are a hiker...How about a short note at the end of your blog on the outlook for hikers, snowshoers, and I suppose, even our speedier friends - the backcountry skiers?

    Thanks (just in case!)


  2. It's not only a disappointment for the kids, it's a disappointment for snow lovers everywhere, kids and adults alike.

    Does water freeze more easily here than in other places? Living east of the Rockies for quite some time, it was never necessary to leave water running or anything unless it was at least below zero for a week - and that was if you were gone. High temperatures in the 20s was normal for months at a time. I'm new to the area, so please help me out - is this seriously something I should be doing?

  3. Nicholas..the problem is that many homes are not properly insulated...something that is less of an issue back east. Most homes will be fine though.

    And regarding Lionel's question...there is now 15-30 inches at pass cross country skiing and snowshoeing season is on. Not really enough for downhill yet...cliff

  4. SIGH, such a waste of cold air. Cold is no fun without some snow.

    Looking at the latest models, I concur. This is a huge snow bust. Out of something like 3 chances of snow for Puget Sound it looks like we will be 0-3 with bitter, un-fun cold, and no snow by Monday.

    Call me skeptical on a rinky dink low coming out of the northwest and improving things Wednesday.

  5. And the dim bulbs on TV don't even know about the PDO, all they can do is recite over and over how this is a La Ninya event.

    This planet is going into a cool phase now - hey, where is all your "global warming" heat to save us ?

  6. Its really coming down now! I am new to the NW and I didn't expect big fluffy flakes like this. Its beautiful!

  7. There is more resistance to the Fraser outbrake than I expected at marysville. The onshore is holding it's own. Bring on some fresh Canadian air...

  8. We've got a good 4" and 20F at Sunseed Farm in Acme (east of the sound at 311' elevation. woohoo!

  9. It's snowing hard on Whidbey this morning and it's pretty likely we'll cancel church services. No firm decision yet, but snow here is really problematic, with our limited abiity to deal with snowy roads.

  10. I do appreciate your blog, but am hesitant to get your book, unless you hired a good proofreader. This post alone has at least seven typos...I finally stopped counting after awhile. :)


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