In case you have missed this thread about SF2: http://combatace.com...e-noticed-this/, this has implications for FE2 also.
If this is TK's plans for SF2 (which sells a lot more than FE2), this means that I would not expect to see any changes for FE2 since Tk's statement in the past is that FE2 does not sell much, so he does not have the time or money to make changes to FE2.
Edit: Stickied because a thorough explanation of the FE2 Campaign Weather Mod is at the end of this thread.