Degree Days for 2016 or a Nice Warm Year

I decided to give a broader picture this year of the various AVAs that produce the majority of the wines in the state. I included various sites within the AVAs because they are not entirely homogenous.

AVA	degree days	rainfall at harvest
Red Mountain (Old)	3525	2.60
Rattlesnake Hills (West)	3504	2.28
Horse Heaven Hills (South)	3446	1.62
Red Mountain (New)	3439	2.35
Wahluke	3258	2.24
Horse Heaven Hills (West)	3110	2.42
Walla Walla	3102	3.14
Rattlesnake Hills (Centeral)	3049	2.49
Horse Heaven Hills (North)	2909	3.18
Rattlesnake Hills (South)	2905	2.82
Yakima Valley	2775	2.92

Red Mountain was the warmest AVA in the state this year, beating out the old champ Wahluke by a large margin. New to our list at number 2, Rattlesnake Hills (West) was not significantly cooler than Red Mountain. Owen Roe Vineyards are located in the Rattlesnake Hills (West). No Virginia, the Rattlesnake Hills AVA does not get cooler the further west you go. Owen Roe had already picked these vines as Red Mountain was just getting started.

Alder Ridge represents Horse Heaven Hills (South) and things were quite toasty there along with the new Red Mountain station.

I can't explain why Wahluke was so much cooler than normal. It was still plenty warm to ripen grapes.

Horse Heaven Hills (West) is represented by McKinley Springs at 1081 feet elevation, was still in lower region III as were Walla Walla, Rattlesnake Hills (Central), and Horse Heaven Hills (North).

The Rattlesnake Hills AVA gets cooler as you go south along the Sunnyside Canal on the Warden Silt loam soils. The Rattlesnake Hills (Central) is the portion of the AVA that is on the Ellensburg Formation aka the ancient cobbles and is slightly warmer at higher elevation.

As usual, the Yakima Valley (Sagebrush Ridge), home to over 11,000 acres of wine grapes, was the coolest of the regions. Harvest there is still going two weeks after everyone else is done.

Rainfall during harvest is important - especially for rot-prone varieties like Riesling, Pinot Noir, and Chardonnay. Horse Heaven Hills (north) and Walla Walla share the record rainfall during September and October.

It might be noted that since the soils are cooler in Washington than California the region classification does not translate directly. Red Mountain grape quality does not compare directly with Lodi or Lake County. 3500 GDD more closely translates to high Region II on the cool soils found in Washington.