On September 3rd, 2019, @PokemonGoApp tweeted news regarding the recurring hourly legendary raid events that have been taking place through the month of August.
The announcement confirms that the event will be returning for the entire month of September from 6 PM to 7 PM.
A blog post was put up on the official announcement page a few minutes later.
In the month of September, Raid Battles featuring Legendary Pokémon will happen more frequently every Wednesday evening at 6–7 p.m. in your local time zone. https://t.co/8VVCSYfbJd pic.twitter.com/Pla3CLYuXQ
— Pokémon GO (@PokemonGoApp) September 3, 2019
This month will have some particularly interesting events. Tomorrow, Raikou, Entei, and Suicune will all be around for the hour with their shiny forms available.
Next week, on September 11th, Deoxys in all its forms will be around for the event.
And the following week, on September 18th, Mewtwo will be available with Psystrike, with the possibility of a shiny Mewtwo!
It is currently unknown what the legendary raid boss could be arriving after Mewtwo. There are a few candidates from Gen 4 that have yet to be released(Regigigas, possibly Darkrai or Arceus).
Full Announcement Text
Trainers,
We’re excited to announce that there will be more Legendary Raid Hours taking place in September! For one hour every Wednesday evening, Raid Battles with the currently featured Legendary Pokémon will happen more frequently.
Date + Time
From 6:00 p.m. to 7:00 p.m. in your local time zone on the following dates:
- September 4, 2019: Raikou, Entei, and Suicune
- September 11, 2019: Deoxys
- September 18, 2019: Mewtwo
- September 25, 2019: To Be Announced
Features
- There will be an increased number of five-star raids during the event hour.
As always, Trainers, be mindful of your surroundings and of others around you while playing Pokémon GO. Stay tuned for more updates.
Happy raiding!
—The Pokémon GO team