The summer was super hot but the autumn is chill and fast. You have a chance to see the city decorated with snow although stable snowing is more about the very end of October or the beginning of November.
If you have time for a meeting in St.Petersburg, write me on discord x-rain#1841 I know 2 more Hiveans, I will ask them if they want/have spare time to join. We could have a chat in a cafe or a walk on one of the days you are here. If you have time for that, of course.