California has a problem with overly aggressive fire suppression over the last 100 years creating a buildup of extra-flammable burnable areas. Literally, you need to let a certain amount of burning go on, continuously over time, so that the burnable areas aren't over-fueled tinderboxes that get very hot, very fast.

Part of this is using controlled burns to mitigate the buildup, another thing that's been under-resourced in California.

I had a discussion at a B and B with a guy who flew F-16s in the USAF, then U2s once they were going to promote him out of flying. He'd just left the service and had retrained to fly Grumman water bombers for Calfire. The problem as I've described it is apparently well-known in the wildfire fighting community in Californa.