It's a Cycas revoluta (a cycad though, not any true palm).

Rain in and off itself should not be the cause of this, unless there a drainage problem.

How cold has it been? I have only seen mine look like this after prolonged subfreezing cold. Can't believe this was an issue in the Bay Area (and I probably get three times as much annual rain as you if not more!)

Cut out the dead parts, the plant should recuperate this season. Cycads are BUILT TO LAST!

Poor drainage will do that. I've got one that wasn't really growing over about 14 years and new fronds kept browning off. Last year while doing some landscaping I built a bit of an embankment that diverted excess water away from the cycad. This year it's been growing well and gained more in less than a year than it had done for the past 14 years.

What causes and did guy that