Weather conditions are a non-permanent, changeable and interactive feature in Pokémon battles. They can be summoned by moves, abilities or be already present in several routes, caves or forests. They affect every Pokémon in the field (except in specific conditions) and may alter the performance of some moves.
However, all weather conditions and their effects will be negated by the ability Cloud Nine.
In Pokémon Uranium, the following weather conditions can be found:
- The Thunderstorm and Fallout conditions are the only weather conditions without a TM that teaches a move that summons them, as well as the only two weather conditions introduced in Uranium.
- Sandstorm and Hail are the only weather conditions where the player can extend their duration when summoned by an ability. Rain and Harsh Sunlight's ability are obtained exclusively as Mega Abilities (though Hinata's Flareon is an exception), while Nuclear Fallout and Thunderstorm currently do not have a stone to extend their duration.