Borrowing much of the great work by @Cobra on the Weewx Weather Driver with External Forecasting driver, I decided to strip out all the pieces I didn't need and focus on the things that I did need. In my case I wanted to pull information from Weewx and set values for capabilities (i.e. has it rained today, what the temperature of my pool is to tie into other automations, the humidity under my house, etc). Update: You can now have 2 rain sources and do and or or with that data to determine if the driver is "wet"/"on" or "dry"/"off".
So that's exactly what this does. It requires you to edit code and to install the Weewx Skin (not originally by me, but the author has left Hubitat so I've archived it and made minor updates). Then you figure out what variables you want and edit the driver to grab those and set them to your local device.
This is not incredibly straightforward, so use at your own risk. It's not pretty but gets the job done for my needs - disabling irrigation, controlling my pool pump & heater, and being notified if there is a humidity issue.
https://github.com/bdwilson/hubitat/blob/master/Weewx
If you have issues setting it up, or know a good way to move the code edits to driver preferences, please let me know and I'll be glad to try and help.