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I would say it is an OU team. Some people would call it a mixed team, but OU does not mean they have to all be OU, it is just an uppper limit, just means no Ubers.
There are legendaries allowed in OU, but not the really good legendaries.
no, weather induced by abilities like drought sandstorm drizzle and stuff are permanent unless someone uses a weather move or uses another permanent weather inducer