News is coming out of the Mt. Wilson area in spurts, and it's hard to know what's going on at any given moment. The latest news (from 14:46 PDT) is that firefighters have been pulled from the mountain itself, the staging area near the base of the mountain is being evacuated, and the fire on the mountain will be fought from the air (presumably by water dumps).
That's not good. Many of the observatory buildings were designed to be fire-resistant, but that doesn't mean there will be no damage, or no severe damage. It's just too early to tell. But it looks like the fire will sweep past the observatory sometime later tonight. I just hope it goes through quickly enough that it does minimal damage. I don't want to see Mt. Wilson go through what Mt. Stromlo did in Australia in 2003.
Astronomer Mike Brown is on Twitter with frequent updates, so he's a good source of up-to-the-minute news.
[Update: JPL resumes normal operations tomorrow, so that's good news!]