Napa Valley Under Freeze Warning, Watch: National Weather Service

NAPA VALLEY, CA — A freeze warning remains in effect for Napa Valley and the North Bay interior valleys from midnight to 10 a.m. Saturday when frost and sub-freezing temperatures as low as 33 are expected, the National Weather Service San Francisco said.

In Napa Valley, the low temp is expected to reach 34 overnight.

Then, from midnight until 10 a.m. Sunday morning, a freeze warning is expected to be in effect and temperatures as low as 36 are possible.

"Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing," the weather service said. "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."

Here is the current seven-day forecast for Napa Valley:

Friday Night
Mostly clear, with a low around 34. North northwest wind 5 to 7 mph becoming calm after midnight.

Saturday
Sunny, with a high near 60. Calm wind becoming south southwest around 6 mph in the afternoon.

Saturday Night
Patchy frost after 5am. Otherwise, partly cloudy, with a low around 35. Calm wind.

Sunday
Areas of frost before 9am. Otherwise, partly sunny, with a high near 60. Calm wind becoming east around 5 mph in the afternoon.

Sunday Night
Partly cloudy, with a low around 37. Calm wind.

Monday
Mostly sunny, with a high near 64.

Monday Night
Mostly clear, with a low around 40.

Tuesday
Sunny, with a high near 63.

Tuesday Night
Mostly clear, with a low around 38.

Wednesday
Mostly sunny, with a high near 62.

Wednesday Night
Partly cloudy, with a low around 39.

Thursday
Mostly sunny, with a high near 62.

Thursday Night
Partly cloudy, with a low around 38.

Friday
Mostly sunny, with a high near 61.