https://www.polygon.com/2018/7/10/17549394/pokemon-go-community-day-july-2018-squirtle

There were a lot of good reasons to be outside last weekend — that beautiful weather! —and a lot of them were Pokémon-related. That’s been true at least once a month since January, thanks to Pokémon Go’s community day events. Throughout 2018, fans have been encouraged to log into the game at a certain time and on a certain day in the hopes of catching a special, popular Pokémon. But July’s community day was the pinnacle of the special events’ success — and a reminder of how far Pokémon Go has come over two years of ebbs and flows.

There’s a dual purpose to community days, which occur worldwide on a designated day. The first is that they give players an increased chance of finding regular and shiny versions of Pokémon like Pikachu, Dratini and Charmander. Each one has an exclusive move as well, if you’re someone who’s hardcore into the battling aspects.