Re: Weather variables - Should it have had the "bruma = 1" value set even after leaving the north? And why aren't the worldspace values filled in? Both show up as 00000000 when it would have been expected one of them at least should be 0000003C.
Re: Bloated Float - When I checked it in TES4Edit, the flags looked fine to me. I guess I need to check closer? I swore the All Natural.esp file had the exterior flag set and it obviously has C.Climate which will override the same flag on the UOP. I'll have a look at those other cells though.
As far as snow, I don't think the IC Waterfront is an appropriate location for it. Lake Rumare, for better or worse, is at sea level. A large body of water like that is going to mitigate the possibility of snowfall to the point where it should only happen rarely, and since we can't get that level of control with the script, it should just not happen. It looks silly for there to be a full on whiteout snowstorm there no matter what. Besides, since that followed me from the mountains, it's just plain wrong
Not to put more work on you, but I think consolidating the various weather ESPs is a good idea and would eliminate some of the confusion and probably simplify maintenance for us in the long run.