Unfortunately, arsonists watch the weather forecasts and plan ahead for their perversions. But it is also true that high winds knock down power lines and otherwise play games with the infrastructure. Good investigation can usually determine the cause.

We have a fire locally, along a major highway, that is also suspicious.....

The first fire Tuesday (labeled the Bernardo Fire iirc) could have been HS kids on a smoke break, but the fires yesterday were highly suspicious as to timing and location. We'll see, no point in speculating while the arson investigators put on their CSI hats; the guys at the podium are speculating enough. It's not like they won't have their A-Team all over this with assistance from state and Federal labs.

That's a quote from the local SD Ch.10 (KGTV). Apparently the points of origin were all at an upwind point of a large open space giving a fire lots of fuel for the wind to push it through.

Edit: link to article
All but one fire burning in San Diego County have a suspicious ignition point

Just an FYI -- 109 degrees F in the backyard. 6 hours ago it was 58 deg F. Fortunately the winds have dropped significantly. Tomorrow should be cooler.

The flags at work are finally showing winds coming in from the west instead of the east. It feels like 6-7 mph down from the 20+ mph on Tuesday. Let's hope this is the break that the firefighters need to knock those fires down.

NOT all fires started downwind of another fire ... which is part of why some are thinking maybe one or more fires were set .... nobody has reported spending much time trying validate this concern ...but hey ...really ...9 big fires in the same day ... never happened before ... and it begs the question because of it.
There were other fires yesterday that got quashed quickly and thus didn't get named since they ended up being kinda small. Like the one adjacent to Interstate 5 that closed northbound traffic for a time. I drove by it today ...not overly large area burned but its right up to the freeway ...
Whether we'll ever know if any were actually set, remains to be seen...but hey there are other places that got little rain just like San Diego Cty and they are hot like SD Cty and they are experiencing Santa Ana winds like SD Cty ....but I don't see them catching fire .....so yeah ... it only makes sense to wonder if someone helped us spend huge money to beat back the flames.
Naturally, having preps and BOBs etc doesn't seem so crazy now that its affecting so many folks.
Unlike fires in past years, this time there are tens of thousands of folks asked to evacuate, some still not back in their homes as also the pwr company hasn't restored pwr that was cut to help mitigate potential spread of fire yesterday...so some still don't have pwr anyway....and its nice and hot ....high 90's or 100's in some places.
So far though ... last I heard only 12 homes burned, 6 damaged and 2 commercial bldgs burned .... but that was a few hrs ago.

I think the HurCon (hurricane condition guide) checklist works better than the FireCon checklist because hurricanes develop more slowly and arguably, more predictably, than wildfires. In some sense, preparing for wildfires is more like preparing for an earthquake than an approaching storm because of their speed and unpredictability in many cases.

In many regions, fire season is year-round nowadays so it's always FireCon 5.

The distance cut-offs in the checklist can be useful--or not. I mean, I've seen wildfires spread great distances in a short period of time during windy conditions, and in other situations, you'll have a wildfire literally close enough to see the flames but life carries on pretty much as normal. I was in LA a few years ago on a busy street and the brown hills less than a couple miles away straight down this busy boulevard were on fire, you could see lots of flames on the hillside and a helicopter doing water drops, but everyone was carrying on like normal. Pretty surreal, actually.

One situation that catches people off guard every time is the sudden wildfire during the day. You leave for work in the morning and everything is fine, then a fire pops up while you're gone that threatens your neighborhood or housing tract, and your pets or grandma or your prized antique rocking chair that George Washington sat in is back at your house but you and a thousand of your neighbors are trying to jam back into your housing tract on the single road leading back there.

In that situation, the authorities may block anyone from going in, so the only way to get, say, your pet out is if (well, besides sneaking in) is to have a neighbor who is already there to bring the pet out.

It may be fire season year round, but it's the high winds / low humidity that raise the risk to FireCon 5. Most of the year, Calfire will knock wildfires down quickly and only a few acres will be scorched. Keep a 50-100 ft perimter around your property and you should be fine. It's when there are gale force Santa Ana winds that can drive a blaze too fast to contain, that you need to prepare to evac.

" In some sense, preparing for wildfires is more like preparing for an earthquake than an approaching storm because of their speed and unpredictability in many cases."

Absolutely. You probably should consider some combination of distance and wind velocity in transitioning between preparedness levels. It is better to leave earlier than later.

I will never forget the smoky, flaming early morning when I couldn't leave my driveway for all the fire engines bumper to bumper straining to get to the advancing fire. Not to worry - it was at least 400 yards away.

Very true. That's another difference between evacuating for a hurricane vs wildfires. Depending on the fire, "evacuating" may mean (at least in a place like Southern California) driving just a couple miles down the road, and then hanging out with your neighbors at some Starbucks parking lot waiting for the authorities to let you back home, rather than driving many miles inland to avoid some massive hurricane bearing down on you.