As the clouds parted briefly Tuesday for a break in the rain, vineyard managers across Sonoma County scrambled to get precious grapes off the vine, racing the clock again before another storm arrived in the evening.
The wet weather hitting the North Coast this week has grape growers concerned they could lose even more of a crop already expected to be 10 percent smaller than normal.
On just about everybody's mind was botrytis, or "bunch rot," a mold that shrivels the grapes and concentrates their flavors. Thinner-skinned grapes like chardonnay, pinot noir and zinfandel are more susceptible to the rot, which is more likely to take hold if a grape's skin splits. And with rain seeping into the soil and trickling up the vine's roots, grapes are getting plumper by the day.
Chardonnay, Sonoma County's largest grape crop at more than 16,000 acres, could be among the hardest hit if the rainy weather continues, in part because the grapes have taken longer to ripen. Especially in cooler regions, there's still a lot hanging on the vines.
The latest storm swooped south from the Gulf of Alaska into California on its way to northern Baja.
It arrived Tuesday night in the North Bay, where it was expected to drop up to 2 inches of rain in the hills and more than an inch in the valleys. To the east, the storm was expected to give the Sierra its first taste of winter, with a foot of snow predicted in the higher elevations.
"All the major Sierra passes will have snow," said Steve Anderson, meteorologist for the National Weather Service.
A few lingering showers could continue through Thursday morning, followed by dry skies in the afternoon.
"It'll be a sunny, dry, warm weekend," said Anderson. "Not in the 80s, we're done with that for a bit. Mid to upper 70s," he said.
Summer ended just two weeks ago, but the North Coast has already been hit by two winter-like storms in just three days. The first arrived Monday morning, dropped more than an inch of rain in several areas and moved out early Tuesday.
In the Carneros region, grower Steve Sangiacomo said his company has harvested only one-third of its 1,100-acre chardonnay crop. His crew set out Tuesday afternoon to harvest another 15 acres.
"It's very hard and nerve-wracking and every other adjective that goes with those," Sangiacomo said.
Growers have already seen some botrytis in the crop this season. Several said it hasn't caused problems so far, but that could change.
"It already has a little bit in it, and with moisture it goes like a fuse," said Harry Merlo, owner of Lago di Merlo Vineyards, based in Dry Creek. His company harvested its white grape varietals, but still has delicate petite syrah grapes on the vine. But he couldn't harvest them on Tuesday because his hilly vineyards were too slippery for the work to be safe.
"There's been a lot of grapes picked since last Thursday or Friday, but I think there's still a lot out on the vine," said Brian Clements of Turrentine Brokerage Group. He guessed that more than half of Sonoma County's chardonnay crop had been harvested, though he said it was difficult to estimate.
A smaller crop could mean real dollar losses for growers. On the spot market, large quantities of chardonnay grapes have been selling for $1,500 to $2,200 per ton, compared to $1,000 to $1,700 last year, Clements said. Pinot noir grapes have been selling for about $1,800 to $2,800, up from $1,200 to $1,800 last year.