Thursday, May 24, 2012

Understanding Ellensburg's Wind

As we move into the late May and June regime of low clouds (a.k.a. June gloom), experienced west side residents know that crossing the Cascades--east of Cle Elum and down into Ellensburg-- can bring welcome sun.  A fancy resort, Suncadia, has been built for sun-starved travelers in Cle Elum, and even more sun can be found if you descend I-90 to Ellensburg and Vantage.  Even Knute Berger, the old mossback, recommends Cle Elum sun in a recent Crosscut piece.

But there is problem.   During just the days when the east-side offers the brightest contrast to the dreary west, westerly winds descend into the Kittitas Valley, causing the stretch from Cle Elum to Vantage to become a wind tunnel, with sustained winds of 20-30 mph and gusts that sometimes hit 50. 

Some folks say that in Ellensburg there is only one four letter word best for cussing: WIND.  And the Ellensburg Safeway has a unique wind measuring devise for their customers.


Now I have enjoyed the Suncadia resort in Cle Elum a few times, but it is sufficiently exposed to the westerly winds that the extensive golf courses are perhaps a bit more of a challenge than novice golfers might have reckoned with.  The golf pro at Suncadia is highly in demand for this insightful lessons in avoiding wind-driven hooks or slices.  Here is a sample (click on picture) that was sent to me by a local golf enthusiast.  Listen to his detailed instructions on the proper swing for windy conditions:


Strong westerly winds are found in this region when there is a large pressure difference across the Cascades, with higher pressure to the west.  Such a large pressure different in most prevalent in the spring and summer.  Why?  In spring high pressure builds northward in the eastern Pacific, while the warming of the interior of eastern Washington leads to pressure falls, since warm air is less dense than cold air.  To illustrate this pressure pattern, here is a 12-h pressure forecast valid 5 PM last Friday, a day when the winds were quite strong in Ellensburg and vicinity:


Air looks for the easiest path across the Cascades, and the Snoqualmie/Stampede Pass complex is the lowest route across (roughly 3000ft) north of the Columbia Gorge.  Cool, cloudy days with strong onshore flow are often associated with high pressure in the west---that can juice the pressure difference and the winds.

Spring and early summer are the best times for strong winds moving into the Kittitas Valley and thus the period of best wind energy potential for the many wind turbines in the area.   Unfortunately, this is the period of greatest snowmelt, streamflow, and hydropower potential--leading to contention between these two sources of clean energy.  Why contention?   Lack of energy transmission capability.  I wish some of the stimulus money could have been used to fix this deficiency.

The UW ultra-high resolution WRF forecasts do a pretty good job in simulating the strong winds along the eastern slopes of the Cascades...here is a sample (the shading shows the sustained wind speed) and the brown lines are sea level pressure.  You will note that the region from Leavenworth to Wenatchee get some winds too..they are downwind of the Stevens Pass gap...a lesser one. 

The strongest winds are often east of Ellensburg on Whiskey Dick mountain--the ridge on which Puget Sound Energy has placed their Wild Horse Wind farm. Very nice visitor center there if you want to visit.  Want sun and no wind?  No problem.  Drive down to Vantage and head north towards Quincy....the winds are less there.


Let me end with a plot of the sustained winds at Ellensburg during the past six months...they can get strong winds any time of the year...but you see the increase around March 1 and the beginning of the spring pressure patterns.

Memorial Day Weekend Outlook

No major storms.
Friday and Saturday will be sunny and seasonably warm (60s).
Clouds and a few sprinkles on Sunday and Monday-highs around 60.





10 comments:

mjgrota said...

That settles it. I am retiring from air quality work and opening a kite shop in E-burg. May sell Tamales on the side.

Have very similar wind regime in the southern Salinas Valley in CA. King City and south to Paso Robles. About to authorize a 9,000 acre controlled burn Camp Roberts on Tuesday. Sparse vegetation but risky. Wish I has the prediction tools here I had in Seattle.

Enoch said...

I've always wondered about the little (and sometimes big)windstorms that invariably happen nearly every time my family and I go on our yearly summer trek to the Sun Lakes resort (not at all fancy, and located next to Sun Lakes state park in eastern WA).

Usually the windstorm begins in the evening, then turns more serious at night, then subsides in the morning. We used to stay in a tent in the campground, but the windstorms made it an unpleasant experience, so we always stay in the cabins now.

Thompsonized said...

Love to see stories on our little slice of heaven out in Eburg :) We have property in the foothills NW of Eburg, and while it is nice and sunny and warm, the "breeze" can be quite a challenge when trying to build something on it! I noticed yesterday, there was not a flag to be found in town that wasn't giving the full salute to passers-by. Love your blog Cliff!

Unknown said...

This explains why, during my annual camping trip to Eprhata, I wake up just about every night with the tent on top of my head (wind blowing so hard that it partially collapses the dome tent during the gusts). Love it :)

By the way - it's thundering here 3 miles NNE of Monroe right now... looks like thunderstorms developing out of the mountains. Good Stuff! Love the blog as always Cliff! Thanks...

smokejumper said...

I lived in Ellensburg for 2 years (CWU) and I tried to solve the wind mystery but never did.

You're right, the lower gap plays a huge role, and the NW trajectory of the valley. But there has to be more to it....because the wind in any other east slope valley is still out of control but so pale in comparison.

I wonder if the enclose to the east, such as Ryegrass Ridge, plays a big role too. Creating a trapped bowl. Meaning, Wenatchee, Omak, Yakima, and even the Columbia Gorge, afternoon heat lows (thermal trough) set up over the Columbia Basin (Hanford area).

But for the case of Kitittas Valley, the thermal low forms within the valley itself, probably in the deepest SE corner called badger pocket.

100% opinion. If you blew up the Mts to the east, the wind would probably blow stronger lol.

smokejumper said...

Omg, I just checked the Seattle radar, why are there tshowers firing off the westslope of the Cascades? We have unusual upslope NE winds today, and its just stable flat cumulus. But on the downward side its raining lol. Bizarro world.

Hindu said...

So I suppose the same effect for us in Tri-Cities. People talk of the Portland/Spokane pressure difference.

Every once in a while (today being one of those rare days) we get winds strong enough from the NE to generate dust storms, although it was limited.

Last year, I think, we had one and NASA posted a photo later of all the dust being lifted from the scablands between Pasco and Spokane blowing to the SW ... where the dust storms usually come from.

Isaac Molitch said...

Love your shared work Cliff, for example this one and the one preceding!
Thanks much.

Rod said...

Hi Cliff,

Pretty interesting weather in West Seattle at approx. 1830 Friday evening. Thunder and rain. Whoa Nellie, as Keith Jackson used to exclaim....

William said...

Excellent work cliff. Very timely. I googled "Ellensburg wind" and found your article. I do question the accuracy of the speed map though - I have never found the Wenatchee area to be quite as windy as Ellensburg (as you point out). Thanks