January 09, 2012

Winter Over? Don't Bet on It!

Bicycling in today, I marveled how spring-like it was.  Mild temperatures well above normal.  The grass is really growing--starting much earlier than normal.  At the UW, I could see large number of bulbs pushing up in the beds.   And it has been warmer than normal for weeks now--take a look at the comparison between Sea-Tacs temps and normal:
The normal high is around 45F and we have been hitting 50F and beyond on a regular basis.  Very good for my lost dog.

The National Weather Service extended forecasts have repeatedly called for a return to normal La Nina conditions--wetter than normal and colder than normal--but it simply has not happened.  However, the latest batch of forecasts from both the U.S. National Weather Service and the European Center for Medium Range Weather Forecasting suggest the possibility for a change to much cooler temperatures.  And in the meantime we will have a period of very little precipitation and even some sun.

The European Center for Medium Range Weather Forecasting (ECMWF) is the gold standard for short and medium range weather prediction.  They have about a day more predictability than the NWS forecast center.  This is completely embarrassing, unnecessary, and a national disgrace.  And a topic for another blog.

My rule is that I don't get too excited until the forecasts get within 120h (Saturday morning)--so here is the 120h forecast from ECMWF for upper level heights (500 hPa) and 850 hPa (roughly 5000 ft) temperature.  Cold air (blue/purple) to our north and a trough just offshore.  This is a threatening pattern for cold/snow.

The forecast for a day later is certainly of concern...cold air is closer, as is the trough.
The NWS model slides the cold air past us to the north...and we are just on the edge in the ECMWF prediction.  The ECMWF ensemble mean forecast (averaging a large number of predictions for the same time) has a very similar pattern.

The bottom line---we have several dry days (guaranteed), but will have to watch the situation carefully this week.  The forecasts are on the edge past Friday.  We could end up with nothing or snowpocalypse.   We will know in two days.

We are still in a La Nina year and remember last year (also La Nina)...warm in January and then we froze over in mid-February.  But also keep in mind we really only have 6 weeks left of winter.  By the end of February, winter is really over in the lowlands.  Snowpack in the mountains can still pile up into early April.


  1. six weeks my foot. winter lasted into august last year.

  2. I noticed you showed the deterministic 500hPa Euro, the sample from their website twice a day.

    Just can't find much except whats on the site. UNISYS has a precip map thats ok. Just wondering if there's any legality of the U.S. using their model, international copyright laws etc. Why isn't there a UW mesomodel but one from Taiwan (aka the coal standard)?

    Ive overused that stupid joke. A blog down the road would be great.

  3. If Snowpocalypse hits this Weekend you better get the dog recovered by leaving out a steak in the park where she was last seen! If she won't come back, we may be due for more than just snow or Unusual Weather, but A quake... They say the pets can predict these...

  4. Hoping for snowpocolypse....but not counting on it! We've been teased so many times this year, only to be dissapointed. I'll make sure I'm prepared for come what may but I'm not getting excited until there's actually snow falling from the sky and sticking to the ground!

  5. Cliff I have learned so much about NW weather from your blog. Todays was confusing, I am not a dork but I could not pick the Puget sound out of the European weather plot...please help

  6. I'm still going the skeptic route. How many times have we seen snow on the forecast that far out and been disappointed? Pretty much every time.

    I don't expect any snow. Overall this winter has been very disappointing.

  7. Lets not forget, last year we were all writing off La Nina in January with a 6 week snow drought. It was warm and drippy.

    Feb and March, followed by a cold April, May, June, and July left us with near record snow pack.

    Things can change fast around here...

  8. Ha! Dry days guaranteed?! Its snowing in Port Orchard(slushing, really) Tuesday morning at 10am! I went out for a walk in the woods thinking it would be dry-didn't check the dopplar like normal. It sure is pretty!! I'm not complaining. But how did this get missed by everyone?

  9. It's always nice when the weather makes it into the nearer layers of popular culture. What's up with the weather? (Boing-Boing's Maggie Koerth-Baker manages to espouse objectivity most of the time)

    There's no neighbor in the north-end that would be willing to set up in their back-yard a spacious live trap baited with Leah's favorite squeak-toy? maybe after the third raccoon it would be Leah's turn? -sigh- good luck!

  10. Jeff Pagel, find a landmark such as Hoods Canal, extend the Hook (say double it and you are in West Seattle), or on a coarser Space Map look for say Vancouver Island and extend it a quarter of its size away from the bottom and you are in Seattle, etc.

  11. Well, well.. looks like the latest GFS is coming into alignment with the ECMWF.. I hate the teases, but if both systems stay together for another day, I think that I may let myself dream of some serious lowland snow.. At the very least, we will have some beautiful cold powder to ski/ride

  12. I have two conflicting weather indicators for you: The northern breed dogs are blowing out their winter coats (predicting warm) AND I didn't buy a season's ski pass this year (predicting a great ski season). Time will tell.

  13. This morning's NOGAPS shows a similar push of cold air into the area. I haven't looked at the latest ECMWF, but both GFS and NOGAPS think it could really start to push into the Pacific Northwest Sunday/Monday. But like Peter I don't want to get my hopes up too much in case things don't hold true.

    Waiting for the evening runs before I write my next blog post, at which time I'll probably write like 30 warnings about how things can change lol.

  14. Worst case scenario we'll get chilly rain in the lowlands and finally some decent mtn snow! The recent NWS scientific weather discussion sounds interesting though, it looks like the models are starting to come into better agreement.

  15. I vote for the snowcpocalypse,too! This old Yankee needs to see some serious snow.

  16. This website has charts for the Euro and other international and national models: http://raleighwx.americanwx.com/models.html

    It's a great site, I use it a lot. I definitely prefer it to the ECMWF site itself.

  17. Snow isn't the story for those of us in the line of fire of the Fraser Valley outflow. Wind is what matters. Seattle-ites, et al may get in a dither about a dusting of potential white stuff, but we have more pressing matters to deal with. So what's our potential reality, Cliff?


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

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