The final growing degree days (GDD) are in and it pretty much tells us what Ste. Mickeys knew a long time ago when they moved their red wine sourcing out of the Yakima Valley - It is too cool to consistently grow Bordeaux varieties in the Yakima Valley. 2010 proved this point well when the Yakima Valley was the coolest growing area in eastern Washington with only 2331 GDD - far below the amount of heat needed for non-herbaceous reds.
Here are the results by AVA:
Last year the warmest AVA title was given to the Rattlesnake Hills. This year it goes to the Horse Heaven Hills. Red Mountain came in second both years. These are all good places for premium red wines. (As a footnote, most of the Horse Heaven Hills wineries and some Wahluke Slope wineries have winery facilities in the city of Prosser (Yakima Valley). This does not make them Yakima Valley wineries per se since their fruit does not come from Prosser Flats.)
All of our fruit at Bonair winery is from our estate vineyards in the Rattlesnake Hills, but we have been labeling the cheap stuff sold in Seattle as Yakima Valley, reserving the Rattlesnake Hills label for our barrel-select wines. In light of this information, I am seriously considering relabeling our inexpensive reds as Columbia Valley. There are lots of areas in the Columbia Valley that are warm enough to grow Bordeaux reds that do not have a more specific AVA or a wine might be from a combination of AVA's where cab grows well. The generic Columbia Valley is not all bad.
Let's reserve Yakima Valley for cool-climate reds like Pinot Noir and nice whites like Chardonnay and Pinot Gris. This will start to give some credence to the AVA's of Washington.