February 12, 2011

Walla Walla Warmth

You want to wake up this morning to 60F temperatures and luxuriate in subtropical warmth? No need to head to California...you can have it here in the Northwest!

The Northwest has a number of "banana belt" regions--locations that get amazing warmth during a few periods of the winter. One I have talked about...the Brookings area, where 70s and 80s can occur anytime of the year with downslope flow off the Siskiyous. But there is another....the towns downwind of the Blue Mountains of NE Oregon...towns such as Walla Walla.

This morning at daybreak Whitman College reported temperatures as high as 61F and other nearby locations were close. Here is the proof:
Lets back up a bit and view the temperatures around region at 7 AM (below, click on maps to enlarge)
58F in Walla Walla (ALW is the ID) and Pendleton (PDT) with forties and thirties in most of the rest of eastern WA. And notice the winds....they are southerly at the warm locations...this will be important.

How about a blow up map of the Walla Walla region at 7 AM? Here it is:

There is clearly a cluster of warmth...and those are associated with southerly flow.

What is going on here? Why does the area north of the Blue Mountains become a hot spot sometime?

We start with relatively warm air aloft ahead of an approaching frontal system (rain will spread southward over western Washington during the afternoon with this front). Also ahead of the front is increasing southerly flow. Such flow heads downslope on the north side of the Blue Mountains and the air is compressed and warmed as it descends. Like your bicycle pump! Here is the upper air data from Boise (upstream of the Blues)...you can see strong southeasterly flow in the lower atmosphere.

And here is a map of the terrain and my artist rendition of the winds (I am no artist!)

Our high resolution models can capture this feature--here is the forecast surface temperature for 7 AM. See the darker yellows on the Oregon/WA border near Walla Walla?And temps should really warm during the day....here is the prediction for 1 PM. Time to head to SE Washington and NE Oregon for summer in February!

So cancel your trip to LA and head to Walla Walla. The wines are better there and Whitman College--the heat wave center---is fun to tour. And then there are the wind turbines to watch...

And tomorrow is looking pretty decent for most of the area--the front moves through tonight leaving some showers tomorrow, but mostly dry. And thankfully the mountains will get a bit of fresh snow at higher elevations. They need it.

Finally, thanks to all of you that have contacted your legislators about HB 1891, which would delay adoption of the Common Core math standards. I hope Representative Santos will allow a hearing on this bill. (If you haven't contacted your legislator and Rep Santos, please consider doing so...see my past blog for info). It is crazy that our state would thrown away our excellent new math standards for standards that have never been used or tested anywhere. Yes, never. And spend tens of millions of dollars to do so. Completely irrational, but unfortunately that is why we have gotten into the education mess we are right now. Rational decision making seems to be an issue in the education community, which acts without facts too many times.


  1. That compressional warming is interesting when artic air is in place. I've seen situations where Walla Walla was near 60 but Hanford was in the teens. Its quick transition, before the whole basin warms up.

    I am so frustrated with our winter since Dec.. Where is our great pacific jetstream! Now after this trough diving into Cali, the jet stays spread over us, but it consolidates into a beast over C and E United States. Just like all dang winter long.

  2. Extremely gusty today along the E. slopes. Balmy too. We receive a lot more post front winds, not pre front winds like today. Weird.

    According to Wunderground, Yakima recorded this states two extremes. Low of 24 and high of 64, lol.

  3. This afternoon, Saturday, at 3:00 p.m., the automatic weather station at Camp Muir reported a gust of 155 (mph?), average at 132, minimum of 107! That's Mt. Washington quality weather. Question: is this credible, or are the reports from those automatic stations unreliable?

  4. Pea sized hail in Tacoma from 517-519pm today. I am part of Cocorahs network, so entered special report.

  5. 150+ mph gusts at Camp Muir today for 2 hours in a row. WOW.

  6. The Camp Muir station data is reliable in general, but note that it says "instruments are unheated and may rime." You can tell when the anemometer is iced up (when the wind velocity is zero for hours on end), or when the wind vane is frozen (constant direction for hours on end). Sometimes the wind vane will be locked by ice for several days, only being released when the ice , falls off, or (rarely) is de-iced by a person. Other facts about the Feb. 12 wind at Camp Muir are: peak wind was 155 mph at about 3 pm Saturday (the highest I have noted in over 4 years since the station was installed in 2006). That is the minimum wind velocity for a Cat. 5 hurricane (although wind in the Saffir-Simpson hurricane rating scale must be wind of at least 1 minute duration, and this storm was definitely no hurricane, which is a tropical storm). For that hour the average wind was 132 mph and the minimum was 107 mph. But even more astounding is that for 27 hours straight, the peak wind never dropped below 100 mph, for ten straight hours the average wind was over 100 mph, and for 23 straight hours the average wind never dropped below the minimum velocity for hurricane force (74 mph continuous), and finally 34 straight hours the minimum wind only once dropped below 42 mph.

  7. I'm a Whitman grad, and I remember having a few lovely 70 degree days in February. It usually warmed up enough to do some great biking around the region. Thanks for explaining why Walla Walla gets so warm!

  8. K. Ross Toole, former University of Montana history professor did not call Montana "The Land of Extremes" for nothing.


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