Is Google app necessary for weather functionality? If yes, what exact version did you use?
I had Gapps in the minimal version (pico) installed, i.e. without Google search app (only with Google framework) But installing google app version 126.96.36.199 (which is about from the date 26/03) didn't help either.
One of them or both have to be enabled. I hadn't yet consistent results with either variation (i.e. sometimes it worked, sometimes not)
If it doesn't work right away it might help to clear data and cache of the Google app and/or play services.
So from a privacy standpoint it might be better to use some other widget or app...