Winter · live

Frost advisory: what it means and what to do

An open cabinet under a kitchen sink in an American home

The National Weather Service says

“A Frost Advisory means areas of frost are expected or occurring, posing a threat to sensitive vegetation.”

weather.gov →

Frost Advisories in effect right now

1 Frost Advisory in effect.

States: California

Frost Advisory until Nov 3, 2026, 12:00 PM ETNorthwestern Interior Mendocino; Northeastern Interior Mendocino; Northern Lake

National Weather Service data, updated Nov 2, 2026, 9:46 PM ET. Not an official warning: follow your local NWS office. All US alerts →

What to do now

Insulate pipes in basements, crawl spaces, attics, garages and along exterior walls, and keep garage doors closed if supply lines run there.
In very cold weather, open cabinet doors under sinks and let cold water drip from faucets served by exposed pipes.
If you leave home in cold weather, keep the heat on and set it no lower than 55°F.
To thaw a frozen pipe, keep the faucet open and apply heat with a hair dryer or heating pad. Never use an open flame.

From our frozen pipes guide, which links every source.

Power out? Find your utility's outage map, and see what a power station or generator will run.Outage maps →

Watch, warning or advisory?

Each in the National Weather Service's own words.

Frost Advisory

“A Frost Advisory means areas of frost are expected or occurring, posing a threat to sensitive vegetation.”

Freeze Warning

“A Freeze Warning is issued when temperatures are forecasted to go below 32°F for a long period of time. This temperature threshold kills some types of commercial crops and residential plants, while temperatures below 28°F for an extended period of time can kill most types of commercial crops and residential plants.”

Freeze Watch

“A Freeze Watch is issued when there is a potential for significant, widespread freezing temperatures within the next 24-36 hours. A Freeze Watch is issued in the autumn until the end of the growing season and in the spring at the start of the growing season.”

A frost advisory is about sensitive plants, not people: cover or bring in tender plants overnight. If temperatures are forecast to drop lower, NWS moves up to a Freeze Watch or Warning, which is when exposed pipes are at risk too.