I know I've talked to JimmyD3 about this, and he had determined it was caused by a type of cloud layer that was above its rated altitude, or something like that. IIRC, he has fixed the map and resubmitted, so I think its just up to Hitech to recompile/rebuild the map - though that may be more work than it sounds like it is. He also may need a reminder?
My advice is to exploit the heck out of this feature while you can. It's been solved and will be going away at some point and probably will be missed by a few!