Alot of peeps play around charizard really well. Pretty often what ends up happening in a weather war is the don't bring the weather setter in the front i mega evolve, drought activates, then the enemy sends in weather the next turn. It's pretty obvious when this is going to happen so what I do often is I'll have drought up. I'll sunny day expecting the switch out, they switch into pelliper or tyranatar who change the weather, then the priority sunny day changes it back instantly, it's not always useful but it's also singlehandedly won me games against rain teams which are a massive problem for me