In the middle of a conversation about roaring fires and Muir Woods' Pelican Inn with San Francisco scribe/on-air talent Beth Spotswood, she informed us that Mill Valley is "blasting the emergency sirens." (Mill Valley, by the way, performs their weekly emergency alarm test on Saturdays.)

We can only assume at this point that it's storm-related. We'll update as soon as we know more.

Update: Brace: turns out it was...just a power surge. That's what set the siren off. Here's what went down:

Beth: "I'm sure everyone's calling..."
Mill Valley City Hall Voice "Yes, they are."
Beth: "But we can hear the Emergency Siren and..."
Mill Valley City Hall Voice: "I know. It was a power surge. It set the alarm off."
Beth: "Okay, thanks. Bye."
Mill Valley City Hall Voice: "Bye."

Electrifying!

Please stay tuned to SFist for more StormWatch2K9 hysteria.