Weather plays a vital role in Pokémon Sword and Shield because certain Pokémon only show up when there’s a particular type of weather happening.
For example, if you visit your PokéDex and look up a Pokémon you want to capture, click on the “Habitat” option by clicking “X.” You’re going to bring up the entire Galar region, and you should see little creature symbols on the map. These symbols indicate locations you can encounter that particular Pokémon. When you hover over one of those locations, you’re going to see specific weather symbols on the upper left of your screen darken, indicating what weather that Pokémon prefers in that region. A Pokémon’s preferred weather changes per area.
Those symbols are helpful to see visually, but there’s no direct name attached to it. We have a break down of those symbols and what they mean. There is a method of how players can change the weather in the Wild Area.