Keep the heat on tonight and grab a blanket or two, because the icy chill in the Bay Area isn't leaving anytime soon, and a dusting of snow is even expected later this week.
The National Weather Service issued a freeze warning for the next few days as conditions will likely be frostier than usual.
The warning was issued for valleys in the north and south bays through Thursday morning, said Bob Benjamin, forecaster for the National Weather Service. Temperatures Wednesday night were expected to range from the low to mid 20s in those areas.
Periods of rain followed by snow could even hit Friday night, Benjamin said.
"It's likely they'll be snow in the higher elevations -- mountain peaks above 2,000 feet like Mt. Diablo and Mt. Hamilton," he said. "Most all of the mountaintops will have some dusting."
The icy cold is expected to arrive Wednesday night and into Thursday morning, when temperatures could drop by 15 degrees in the central and eastern parts of Contra Costa County, as well as the easternmost area of Alameda County, Benjamin said. Temperatures in cities such as Concord, Walnut Creek, Antioch and Livermore are expected to dip to as low as 27 degrees.
The South Bay and the Peninsula should bottom out in the mid 20s early Thursday, and forecasters said there is a freeze watch for the Bay Area through Thursday.
Temperatures in San Francisco also were expected to fall into the 30s on Wednesday, and Santa Cruz could see temperatures as low as 30 degrees, Benjamin said.
Throughout the Bay Area, homeless shelters were prepared for the cold spell. In San Jose, EHC LifeBuilders launched its Cold Weather Shelter Program on Monday, creating 125 emergency beds at the former Sunnyvale National Guard Armory, 100 at the Gilroy National Guard Armory and 50 at the Boccardo Reception Center.
On Tuesday night the shelters had enough beds but Jenny Niklaus, CEO of LifeBuilders, said that when the sun goes down, they expect to be at full capacity, if not over it.
"We'll be adding beds as we're able," Niklaus said. "We are also increasing our hours at all three of our locations and will stay open later in the mornings through Monday. Our goal is to turn nobody away during this cold snap."
Niklaus said cold weather often exacerbates other medical conditions such as diabetes or heart disease.
In Oakland, the Henry Robinson Multi-Services Center has replaced the now-closed Oakland Army Center as a haven for those who receive a referral from agencies that work with the homeless, said city of Oakland spokeswoman Dana Perez-St. Denis.
On Tuesday night, the shelter was more than three-quarters full, Perez-St. Denis said.
"We had 36 out of 50 beds filled last night but they are filling up fast (Wednesday)," she said Wednesday.
The Salvation Army, CityTeam and Crossroads at 7515 International Blvd. in Oakland also will offer housing during the cold weather.
In Contra Costa County, homeless shelters such as the Bay Area Rescue Mission in Richmond were expecting to house more people than normal.
"We're going to be able to take our dining area and put sleeping bags in there," said Gary Kingsbury, the vice president of operations for the shelter. "It helps temporarily."
Those who may have shelter but lack heat are advised by public safety authorities to dress in layers, use thick blankets and to keep their feet covered with socks. They also are advised to move into a shelter with heat, if possible.
Outdoor plants and pipes also are at risk during the cold weather, authorities said. Plant-lovers are encouraged to get plants under shelter or inside a house because buildings give off radiant heat. Using newspaper, cardboard, tarps and sheets to tent over a plant also helps, authorities said. The Contra Costa Water District said wrapping pipes in bubble wrap or newspapers can keep pipes from freezing.
The cold system also could trap pollution in the air by the week's end, according to Bay Area Air Quality Management District spokesman Tom Flannigan, though no Spare the Air alerts have been forecast.