In Pokémon GO a legendary raid hour is likely starting again this evening on May 1st. Players from New Zealand, where the event has already begun, report this.
This is what the event is about: When the event starts, every open gym will host a legendary raid. This will hatch at 6 PM, and you can raid at every gym for one hour.
This event first occurred on Good Friday. Surprisingly, you could encounter Latios more frequently for one hour. Such an event is comparable to the legendary lunch break.
When does it start? Tonight, on May 1st, at 6 PM German time, this event will likely start. It will run for exactly one hour.
All information about the legendary raid hour on May 1st.
This is what players report: Initially, there are again reports from trainers in New Zealand. It was already 6 PM on May 1st, and New Zealand trainers are showing screenshots of the numerous legendary raids.

In the coming hours, other countries will likely report on the raid hour.
Is the raid hour confirmed? Niantic hasn’t officially confirmed anything yet. This wasn’t the case the last time either.
Since we now know such an event, and players from New Zealand provide the same reports again, one can assume there will be a raid hour. However, this is not confirmed.
Update 3:15 PM: More and more countries are reporting the legendary raid hour. It will likely happen here at 6 PM as well.
What happens during the event? For one hour you can encounter Groudon more frequently in raids. The legendary Ground-type Pokémon can also be found as shiny.
Every open gym gets a legendary raid that runs from 6 PM to 7 PM.
These gyms do not host raids: During the event, almost all gyms will have 5-star raids. However, there are some exceptions. These include gyms that have a raid just before 6 PM. That raid will continue normally.
Another exception includes gyms where an EX raid has been triggered. If invitations are currently being sent out there, then no raid will take place.
Which Pokémon you can encounter besides Groudon in the raids can be found here:
