NAPA, Calif. (KGO) -- In Wine Country, there's a lot of concern about the extreme heat that's coming. It's moved up the timeline on harvest leaving growers scrambling to protect grapes still on the vine from the sun's punishing rays.
Brooks Painter is in the business of growing grapes, not raisins.
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"When we pick the clusters, we'll avoid these, they're shriveled," said Painter.
This weekend, scorching temps may change the game for Cabernet and Merlot grapes.
"The clusters that get exposed like that, just get cooked," he added.
Painter is chief winemaker at V. Sattui Winery in St. Helena where they've seen hot weather come and go but rarely do they see a stretch of triple digits that's now forecasted.
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"I'm getting calls from grape growers they want to put their grapes on schedule for next week, there's concerned," said Painter.
The winery's lab is testing grapes daily for sugar content, acid, and tartness.
Meantime, there's a rush to harvest Chardonnay grapes from the vineyard before the extreme heat sets in.
"Everything is running together, we're going full bore," said Painter.
Oakville Ranch winemaker Jennifer Rue took us to the place she's most concerned about in her vineyard, red grapes which bear the brunt of the hot afternoon sun.
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"All those flavors get degraded by super high temperatures," said Rue.
Vines at risk are being wrapped in shade cloth. Other grapes were keeping their cool with water spritz, which is a misting system that automatically turns on when temperatures hit 95 degrees.
"It's a super fine mist, it will help keep canopy down," Rue added.
Grape growers are doing all they can to protect their precious commodity but the drought is not helping.
"After three years of drought, the ground is baked," Painter said.
This weekend it means turning up the irrigation drip and hoping for the best.
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