It would be really handy if the app could be ported to the Apple Watch and Android counterparts.
I’m adding my vote to an Apple Watch app, with complications for at least the temperature circle complication on all applicable faces (incl. the Infograph Modular face). I’d love a middle complication with hourly forecast details like Forecast Bar, Carrot, or Snowflake does.
For those with Apple Watches and want something in the mean time, I use Forecast Bar for the middle complication on my Infograph Module face (which pulls data from Weather Underground when you’re within a certain distance of your weather station, configured with the iPhone app), and also Carriot weather for the temperature circle complication which does the same thing with Weather Underground. (You could use one or the other for both, but I’ve found Forecast Bar to be slightly more reliable in pulling data from WU timely than Carrot for some reason, and I love their sunset/sunrise circle complication.)