Frost 'one more thing' for grape growers Santa Rosa, CA

A record cold snap in Mendocino County over the weekend caused little damage to wine grapes but chilled the hearts of farmers who already have suffered huge losses this year.

"It's just one more thing on top of one more thing. You kind of hold your breath," said Potter Valley wine grape grower Bill Pauli.

Temperatures dropped to 31 degrees in the Ukiah Valley on Saturday night and early Sunday morning, the coldest Oct. 12 morning since record keeping began in Ukiah in 1893, said Troy Nicolini, a meteorologist with the National Weather Service in Eureka. The previous record was 34 degrees in 1916.

Temperatures were milder in Sonoma County, and there were no reports of frost-related problems, county officials said.

Farmers in Redwood Valley and other cooler regions in Mendocino County reported temperatures as low as 27 degrees.

An estimated 30 percent to 50 percent of that county's wine grape crop had yet to be harvested when the frost hit, killing the tops of unprotected vines and effectively freezing the ripening process.
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Mendocino County wine-grape growers were fearful because they already had lost an estimated 30 percent of their crop to frost in the early spring. The crop also was hit by an early rain that threatened to cause rot, and the region endured a wildfire-choked summer that had the potential to cause smoke damage.