"We woke to neighbors banging on the doors saying, 'Get out of there, get out of there,'" said Boulder Creek resident Jane Wohlhueter.
The Bear Fire initially started as a structure fire before spreading to surrounding brush. Investigators are still trying to determine what caused it. The dry conditions aren't helping.
"All around us these madrone trees, these redwoods, and all of the litter on the floor burn almost as well as if they're dead fuel," said Cal Fire spokesperson Angela Bernheisel.
Because of the threat, more than 150 homes in a four-mile diameter around the fire were evacuated overnight.
One family found shelter at the Zayante Fire Station in Felton, which is one of two official evacuation centers.
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"The packing up is a frantic time," said Wohlhueter. "Grabbing passports, grabbing phones, forgot the chargers, grabbing toothbrushes, and you know a comforter here a pair of boots there."
At least four structures have been destroyed.
So far the weather has been favorable for crews. But the steep terrain has been challenging to navigate.
Cal Fire officials say of the roughly 600 personnel currently on the ground, five firefighters have suffered minor injuries.
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"When the material up the slope is burning, what happens is that it breaks apart and starts rolling down the hill and it rolls down below where they're putting the fire lines in," Bernheisel said.
Nine helicopters are also being used to fight the flames.
Those who live nearby say they're grateful for the prompt response.
"We have ourselves, we have our kids, we have our dogs, and we'll work it out," said Wohlhueter.
But for now, it's a community unsure of when they'll be able to return home.