SAN FRANCISCO, CALIFORNIA – JULY 30: A pedestrian walks by a fog-shrouded Golden Gate Bridge on July 30, 2025 in San Francisco, California. As summer temperatures soar to record highs across much of the U.S., San Francisco is experiencing a historically cold summer as a persistent marine layer hangs over the city on most days, keeping daily temperatures in the 50s and 60s. The constant fog has produced five days of measurable precipitation in July for the first time since 1850. Since May, San Francisco has only once reached a daytime high temperature of 70 degrees. (Photo by Justin Sullivan/Getty Images)

...

Anna Skinner

By Anna Skinner

Associate News Editor

0

Share

Newsweek is a Trust Project member

See more of our trusted coverage when you search.Prefer Newsweek on Googleto see more of our trusted coverage when you search.

Unseasonably cold and even dangerously low temperatures will sweep across part of Central California later this week, putting millions at risk of hypothermia.

An extreme cold watch has been issued for vast regions of California, encompassing more than 4 million people. The weather alert, announced by the National Weather Service (NWS) San Francisco office on Wednesday, emphasizes increased danger to unhoused individuals, sensitive populations, pets, and vital crops across urban and agricultural sectors. Such a pronounced cold is rare for the region, with the potential to affect health, local food supply, and infrastructure.

The alert impacts a sweeping area including the Marin Coastal Range, North Bay Interior Valleys, San Francisco Bay Shoreline, East Bay Interior Valleys, Santa Cruz Mountains, Santa Clara Valley and East Bay Hills, Santa Lucia Mountains, the Salinas and Carmel Valleys, parts of Monterey County, and other nearby regions. The watch is in effect from late Thursday night through Friday morning, specifically between 1 a.m. and 9 a.m. on January 9.

Read More on News

A pedestrian wears a sweatshirt as they walk by the Golden Gate Bridge. Unusually cold temperatures will hit the San Francisco Bay Area on Friday, posing dangers of hypothermia for millions.

...

Temperatures could dip as low as the upper 20s in interior Monterey and San Benito counties, with low to mid-30s expected in other areas. The forecasted lows are around 8 to 10 degrees below average for this time of year.

"Temperatures that are 35 degrees Fahrenheit or colder can be dangerous to be outside for those who don't have a place to stay," NWS San Francisco meteorologist Rick Canepa told Newsweek. It can be deadly for those who don't have proper shelter."

Canepa said such low temperatures could also freeze pipes and be dangerous for outdoor pets as well.

"Cold conditions will be hazardous to sensitive populations such as unhoused individuals," the extreme cold watch said. "Cold conditions may damage or kill sensitive crops, plants, and vegetation if appropriate precautions are not taken. Prolonged exposure to the cold conditions will lead to hypothermia for people, pets, and livestock."

The watch will likely be upgraded to an extreme cold warning as the frigid temperatures arrive.

Authorities are urging residents to prepare by ensuring that portable heaters are functioning safely and warning against the use of generators or grills indoors, due to the risk of carbon monoxide poisoning.

"Check with your local, city, or county officials for information on available warming centers," the extreme cold watch said. "Be sure to dress in layers if outdoors. Make sure that pets and livestock have adequate food, unfrozen water, and warmth. Cover or tend to sensitive crops, plants, and vegetation."

Looking forward, Canepa said there will be gradual warming on Saturday, with low temperatures closer to their averages for this time of year.

View 0 Comments

Request Reprint & Licensing

Submit Correction

View Editorial & AI Guidelines