Pokemon GO Community Day featuring Mareep has barely concluded and the May Community Day's details were already leaked. This one will feature Charmander and it is scheduled for 19 May 2018 which is the first time it will happen on Saturday.
Community Day will kick off at different times, depending on your region and timezone. It will start at 11 AM and finish at 2 PM PDT for USA and as you can see, it will have the standard three hour format. Europe and Africa will have the event from 10 AM to 1 PM GMT with Asia's version running from 12 PM to 3 PM JST.
Just like in previous Community Days, activated Lure Modules will last for three hours and players will get three times the normal amount of Stardust upon catching a Pokemon.
Charmander's spawns will be greatly increased during the event and special ability will be unlocked upon fully evolving Charmander during the event. Speaking of which, the full evolution will yield a Charizard, one of the most popular monsters in the Pokemon universe. It is assumed that Burn Blast will be the special ability he will gain during the event.
The official page hasn't been altered for over a day after the leak which probably means Niantic are going to officially announce the Charizard Community Day sooner rather than later. Don't let the confuse you with the listed time though, it either refers to a different time zone or is just wrong info at the moment. It's hard to imagine Niantic would launch the event at 5 AM in Europe.
A large portion of this info comes from the Japanese version of the Community Day site, which can be translated to other languages through browser plugins. Most of the pictures there still reference the fourth Community Day with selfies people took when Mareep was around, but the announcement clearly refers to Charmander and the Community Day planned for May.
Charizard is one of the most popular Fire-type Pokemon, and the allure of a shiny Charizard will likely draw crowd in unprecedented numbers, easily setting the May Community Day up as the most popular to date. The possibility of getting a Shiny Charizard will definitely put players into overdrive.