In Puget Sound, 2011 is turning out to be the coolest year on record for grape growing. Currently, we’re approximately 4 weeks behind normal heat accumulation, and a full week behind 2010 which was terribly cool. According to the WSU site (at Mt Vernon, but the best records for Western Washington), Puget Sound has had 1054 degree days this season (we need 1600 or so to ripen the cool climate varieties). Cf. WSU Washington AVA records.
My own Regent grapes have great-looking clusters, definitely well-rested after the poor showing in 2010. But veraison has not started at all, and with 6 weeks needed between color change and harvest, we’re pushing late October (and rain potential) for harvest.
This has me wondering about one model of what climate change might bring: that heat inland forces air to rise there, which then pulls in more marine layer from the Pacific Ocean. Under that model, places like Napa Valley that have coastal outlets could get cooler and wetter (while the central valleys bake). Decanter article here. This might make sense in Puget Sound, too: south sound, foothills, and eastern areas would heat up, pulling in cool air, and making Puget Sound that much cooler and wetter. I hope not!
So I’m keeping my fingers crossed that the rains will hold off until November, and the “month-late” pattern will persist with sun until then.