There’s a screen shot of the weather information that was available in January 2021 release notes if anyone wants a refresher or for those who didn’t see it.
It wasn’t a layer back then, it was more of a point and click tool. You would click on the weather button to enable it, then click somewhere on the map, and it’d pop open a modal displaying the weather for that area - a bit like the way the Elevation tool works.
There was no forecast data, just the current observations.
If people would like a more visual layer of some sorts with forecast capabilities then please discuss your requirement here. If it gets enough interest or requests we’ll add it to the roadmap. 
And if you know an accurate source of weather forecast data that has APIs available, that’d be really useful too 