Strong winds and heavy rains expected to begin Tuesday in the Santa Cruz Mountains are prompting mandatory evacuations with potential flooding and debris flows.
Officials are warning people living near wildfire burn scars to pack a bag and be ready to go on short notice. Evacuation orders are posted for areas around Felton, Ben Lomond and Boulder Creek, impacting approximately 2,800 homes and 5,000 people.
Late Monday, CAL FIRE also ordered evacuations in parts of San Mateo County.
Winds are expected to blow down fire-damaged trees and possibly electrical lines. Rains are going to be intense, too.
"We are worried about 1/3 of an inch in 15 minutes, and 1/2 of an inch within 30 minutes, or 7/10 of an inch within an hour," National Weather Service Meteorologist Brayden Murdoch explained of the forecast, which includes 10 or more inches of rain in the higher elevations of the mountains. "Those our our thresholds to be worried about debris flow."
The forecast is for potentially 10 inches or more of rain at the higher elevations:
Santa Cruz itself could see six to eight inches of rain.
Three evacuation points - not shelters - have already been established at San Lorenzo Valley High School, Scotts Valley Community Center and Pacific Elementary in Davenport.
Over the weekend, the National Weather Service projected the storms will bring the most rainfall the Bay Area has seen so far this winter.
CAL FIRE officials issued an evacuation warning Sunday night for the San Lorenzo Valley area and the north coast of Santa Cruz County. The latest evacuation warnings can be found here.
"We’re not very concerned, from a debris flow standpoint, about the rains earlier in the week, but beginning late Tuesday, early Wednesday morning, that system is a bit of a concern," said Jason Hoffman with Santa Cruz County.
Hoffman told KCBS Radio that the intensity of the rain will determine their response. "For example, if we get rain exceeding a half inch over a half hour, that is probably going to be triggering for our evacuations in the Santa Cruz Mountains area," he said.
There are also concerns for heavy rains in Napa and Sonoma burn scars.
Santa Rosa Fire Department Assistant Fire Marshal Paul Lowenthal told KCBS Radio that property owners in and among fire-ravaged areas need to keep their eyes open and listen for emergency alerts.
"We really are focusing our attention on it, making sure that our residents are prepared, they’re paying attention to a lot of the messaging we’re putting out, having their cell phones on and prepared to receive alerts if we do activate them for the potential of a debris flow or mudslide," he said.