How Cold Was This Year and How Does the Winkler Scale work

The Winkler Scale was developed to classify grape growing regions to help farmers and wineries plant the appropriate varieties for the climate. In summary, it looks like this.

<2500 GDD – Region I – It is similar to Burgundy, Champagne, Rhine, and the Willamette Valley. Recommended grapes include Chardonnay, Pinot Noir, and Riesling.

2500-3000 GDD - Region II – It is similar to Bordeaux and the Napa Valley. Recommended grapes include all region I grapes plus Cabernet Sauvignon, Sauvignon Blanc, Cabernet Franc, and Merlot.

3000-3500 GDD – Region III – it is similar to the Rhone Valley, Lake County, and Lodi. Recommended grapes include Syrah and Zinfandel.

The growing season ended October 31, even though harvest is still going on. Here is the scoop:

Wahluke	3070
Red Mountain	2715
Mattawa	2680
Horse Heaven	2662
Walla	2562
Rattlesnake	2545
Prosser Flats	2199

Wahluke claims 3070 degree days, which puts it into California Region III (Lodi and Lake County) even in a cool year. Nearby Mattawa registered 2680 – somewhat cooler near the river. Wahluke consistently ranks in Region III and is the warmest AVA in Washington.

 Red Mountain did well in this cool year with 2715. Horse Heaven came in next with 2662 and Rattlesnake Hills and Walla are virtually tied at 2554 and 2562 respectively. All of these AVAs consistently rank in Region II, just like the Napa Valley and Bordeaux.

All the major AVA’s did okay in this cool year and should produce good wines and in particular Bordeaux reds without vegetative flavors.

Sagebrush Ridge as usual was quite cool with only 2199 growing degree days. Here is the data for the last five years:

2011                2199

2010                2331

2009                2665

2008                2400

2007                2364

It is clear that the Yakima Valley (most of the grapes are grown on Sagebrush Ridge) should be classified as Region I.  Unlike what some folks with PhDs from UC Davis say, Sagebrush Ridge is NOT the same climate as the Rattlesnake Hills. It is definitely cooler down there in Prosser Flats. This was not a good year for Yakima Valley Cabernet Sauvignon.

Rain was a factor this year with bunch rot with rot-prone varieties like Riesling, Chardonnay, and Pinot Noir. The rain award goes to Walla with 1.31 inches during the fall ripening season (September 1 to October 31.) Red Mountain received the least with only 0.33 in.

The first day of frost was almost uniform across the region occurring either October 24 or 25 with the exception of Red Mountain and higher areas in the Rattlesnake Hills. As of November 4 it has not frosted above 1100 feet in the Rattlesnake Hills.