I’m a fan of the very light, widget-only AF Weather. All it does is a chart showing temp & precipitation for the next 24hrs. I like it more than “hourly” forecasts in other apps, but it is pretty niche.

https://github.com/Gitsaibot/AF-Weather-Widget

https://f-droid.org/en/packages/net.gitsaibot.af/

This one, I presume?

wX (Weather app geared towards storm chasers, meteorologists and weather enthusiasts)

https://f-droid.org/packages/joshuatee.wx/