Basically Gadgetbridge on Android doesn't provide weather out of the box - you have to add something to provide the weather to it. Once that's done it should work for you though
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It's worth checking what it says at https://banglejs.com/apps/?id=weather&readme
Basically Gadgetbridge on Android doesn't provide weather out of the box - you have to add something to provide the weather to it. Once that's done it should work for you though