Nate,
I was having this problem as well with 3 different units. One hw 2.1, two with 2.2, running different firmwares, 2.14 and 2.16. After pulling my hair out and scanning the json settings in each, I decided to reconfigure one completely and then the weather started pulling again. So I saved the settings and imported the file in to the other two controllers and they started working. So I reverted back to the previous settings and it stopped. Long story made short, here is what was the problem, it was the gps point pulled using the location finder for the weather. I know you said you setup the weather properly and I am sure you did. But try to relocate the location on the map and pull an updated GPS location and save and test it.
The new 2.16 in the change write up which I read after resolving my weather update problem, there is now a way to set a specific location up. I have not done this yet, after updating my gps location and saving my settings I have not had this problem. So see if this resolves it for you.
Please follow up in your thread to confirm if it resolved you issue or not. Hopefully Ray or Samers can add a note when testing the weather diagnostics, if it fails that they can add it the notes to re-aquire the gps for your location or refer to setting the location.