"Oh my gosh, it's been so cold," said Marilyn Birmingham from Novato.
How cold has it been in the North Bay? Cold enough for ice to build up on car windshields. Plants were frosty on Sunday morning after temperatures dipped below freezing.
"I'm afraid to look at PG&E because I've been running the heat, because it's been so cold," Birmingham said.
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Birmingham and her son were at Pini Ace Hardware in Novato, grabbing insulation to protect their water pipes at home from freezing.
"Because it's happened before, and it would burst. This morning when I was in the kitchen, the warm water was barely coming out. I thought, uh oh," Birmingham said.
Cold weather, coupled with a small earthquake Saturday morning may have caused a water main to break in San Francisco's Diamond Heights neighborhood. The break sent water pouring into four homes for at least 45 minutes before the water was shut off.
"I'm thinking it was temperature. I've lived in other parts of the country where we've had pipes break. This is the same exact sudden rupture," said homeowner Morgan Kelleher.
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"It was like 22 degrees the other day," said Loren Poncia from Tomales Bay.
Keeping warm is top of mind for many. Space heaters are hot items during this cold snap. The hardware store is averaging three shipments per week to keep up with demand.
Poncia was buying all the heaters he could for his Airbnb ranch in Tomales Bay.
"I have some little cabins, I want to keep warm so we're getting some space heaters to put in each cabin to keep the pipes warm and to keep us warm, because it's pretty chilly," Poncia said.
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Last week, several warming centers opened in Sonoma County, providing overnight shelter for unhoused people.
Marin Humane is reminding pet owners this week how important it is to protect dogs and cats from the cold. The four-legged shelter crew was keeping warm in holiday sweaters.
"If it's uncomfortably cold for us, it's uncomfortably cold for them," said Lisa Bloch from Marin Humane.