While this is strongly noted that this is a theory, it’s apparently been holding up and doing the job. There’s plenty of evidence to suggest it’s legit, but you’ll be wanting to try it yourself to be sure.
Quite simply, make sure you’re in an area where all of the following criteria are met: no streets, gyms, or Pokestops are nearby, and where no Pokemon Nests Are, Once you’ve done that, you should start seeing more and more rare Pokemon turn up, ready to be caught as the system is required to randomly generate different Pokemon due to it being a new area.
This theory is from a video on youtube from a user named IbexPvP You should check it out to get full details on how this theory works.
Let us know in the comment section if this worked out for you, I’ll be trying it out later on tonight as the heat wave cools down or I may just wait til it’s over. Be sure to like our Pokemon Go page for news and tips about Pokemon GO.