Harvest might be coming early for northern California, as a recent heat wave – with several days over 100°F (37.7°C) in Napa and Sonoma Counties – moved up the timetable for grapes that were already precocious. However, it's way too soon to tell what the quality will be like.
"People get a little wiggy about heat, especially with global warming as the backdrop," says Jeff Smith, owner of Hourglass Wines. "The heat we had a couple weeks ago worked to our favor because of the timing."
The scorching days in the beginning of July came before most vines in the area went through veraison, which meant that the growth of the vines themselves slowed down, Smith said. However, the berries that will eventually become $150 cabernets were unaffected.
Another heat wave at the end of the month would be bad, possibly accelerating sugar development without concurrent flavor development. But right now, temperatures have cooled, the days are sunny and dry, and it's full-speed ahead.
Large wineries are worried about where to ferment a crop that's due sooner than usual.
Sparkling-wine producers always pick first, and Mumm Napa might start as early as July 22, which would be one of their earliest harvests ever.
"The crop looks good and healthy at this point, with yields slightly above average," says Mumm Napa winemaker Ludovic Dervin.
J. Vineyards & Winery spokesman George Rose thinks 2013 might be one of the largest on record in California, and that would be two in a row.
Last year's harvest was so huge, after under-size vintages in 2010 and 2011, that big wineries like E. & J. Gallo are trying to rent tank space to move red wines that haven't yet been bottled. Smith says it's not an issue for smaller vintners, who don't have a complicated schedule for use of their facilities.
"I know everybody tries to go out and do early projections on when they're going to pick and how big their crop is going to be," Smith explains. "For the big corporate guys, that's important. For the little guys, we don't worry so much about that."
For consumers, back-to-back large harvests could mean lower wine prices – but let's not get our hopes too high until the grapes are in the tanks.