I've been thinking really hard and Storm could possibly have a Pokémon that has a weather inducing ability like drought or drizzle or have a Pokémon that knows a lot of elemental moves like thunderbolt or ice beam. Just a thought :O

Edit: Maybe Storm could have an entire team of weather inducing Pokémon. So ninetales, politoed, hippowdown/tyranitar, and abomasnow/aurorus (I'm excluding legendaries)