Napa Valley, North Bay Under Freeze Warning

NAPA VALLEY, CA — The National Weather Service issued a freeze warning for the mountains and interior valleys in the North Bay late Tuesday night and Wednesday morning because of dangerously low temperatures expected.

The freeze warning encompasses Napa Valley and is expected to remain in effect from 1 a.m.-9 a.m. Wednesday.

Temperatures may dip as low as the upper 20s or lower 30s in the North Bay valleys and only slightly warmer in the mid-30s or low 40s along the coast and near the Bay, according to the weather service.

"Sub-freezing temperatures of 28 to 32 degrees expected," the weather service said. "Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing."

For Napa, AccuWeather forecast a low temperature of 33 degrees Wednesday night into Thursday morning; a low temp of 35 in St. Helena; 36 in Calistoga; 34 in Yountville; 31 in Angwin; and 34 in American Canyon.

According to weather officials, residents should take steps now to protect tender plants from the cold.

"To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above-ground pipes to protect them from freezing."

Rain that came through the region earlier this week is expected to stay away Wednesday, but precipitation is expected to return Thursday afternoon into Friday morning, with additional rain possible later Friday through Sunday. Up to 2 to 3 inches of rain are possible by the end of the weekend in coastal mountain areas, weather service officials said.

—Bay City News Service contributed to this report.