Following the delay due to extreme weather in Japan, Niantic announced that Squirtle Community Day and Articuno Day will be held on August 4, 2018 in Japan. Articuno Day will run from 12:00 to 15:00 JST and the Squirtle spawns run from 3:00 p.m. to 6:00 p.m. In addition, the special bonus of XP that was won in the Dortmund Safari Zone will run in Japan during the period.
Source: Serebii