RELATED: Your accuweather forecast
"It's time to be on full alert," said Ernie Hubbard, who is getting ready for a rough ride on his houseboat in Sausalito.
The phenomena called king tide is now on a collision course with a winter storm headed right for the Bay Area.
"If you get a 30 mile per hour winds on top of rain and high tides, king tides then you've got an unprecedented situation," added Hubbard.
Not only is Hubbard battening down the hatches, he's having houseboat lines secured to pilings.
"If pilings are not in good condition they can actually break and then the whole house will float away," said Court Mast, a houseboat repairman.
This week king tides are high and have flooded roads in Southern Marin.
Two years ago a winter storm and king tides collided. The Shoreline Highway was underwater and parts of Highway 101 were flooded creating an epic traffic backup.
Mill Valley Fire Chief Michael St. John is monitoring the weather. "We've got a tide over 7 feet on Wednesday, and on Thursday we've got a 6 foot 9 tide, about an inch less, but from experience we know a good storm surge can make up for that."
The Marin County Sheriff's Department is sending weather alerts to subscribers, warning of heavy rain and possible flooding. Drivers are urged to be careful out on the roads. It will be stormy.
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