Fires have been burning in Los Angeles and Ventura counties for much of the past two weeks, and I’ve been watching them, so I decided to make a map.

The map above is entirely self-hosted and built with free, open source tools. The code is on Github. Github Pages is serving all of the assets, and if you cloned the repo, installed dependencies and ran the build scripts, you could turn off your wifi and still use the map.

I started with the self-hosted map template I built for NICAR 2024 in Baltimore. The fire boundaries come from the National Interagency Fire Center.

All of the build steps happen inside the publish workflow, which means I don’t have to check big GeoJSON or PMTiles files into git.

One thing that tripped me up: For some reason, when I generated tiles from the wildfire GeoJSON file, several were missing, including the Palisades and Eaton fires. I’m not sure why. I ended up filtering down the GeoJSON to the same bounds as the base map using fiona, which gives me a small enough file to just serve whole. You might also see parts of both fires disappear if you zoom all the way in.

I kept this map deliberately minimalist, and it could be out of date tomorrow. If you’re looking for up-to-date information on the fires, LAist and the LA Times have been dong great work, and I’m genuinely impressed by Watch Duty.

I might keep tinkering on this, or bundle up some of the tools into a new template repo and Github Actions. The tools keep getting better, and it should be easier for people to self-host maps like this.