I've poked around in there. Think of live tiles as the latest version of desktop gadgets. I installed the weather channel free app, I now see local weather when I hit start.
The MSN Weather app is preinstalled with Windows 10, and has the same basic capabilities. And since you don't need to install it, doesn't require you sign into a Microsoft account. (I actually like setting up this app on enterprise users' start menu, it's a nice extra. And they don't have Microsoft accounts connected.)
The built-in weather app and tile is solid enough that I find people downloading a third party one kinda surprising.
I think I saw it on a list of windows 10 apps to get somewhere. Clicking on it gets you a radar map. Really it was half weather, half trying out the windows store experience.
The built-in weather app and tile is solid enough that I find people downloading a third party one kinda surprising.