It’s still only August, but it seems like autumn has arrived early. I first noticed about 2 weeks ago that many of the trees in this area (western NC, US) are already changing to their fall colors. Normally this doesn’t start to happen in this part of the country until mid-late September, so this is about a month ahead of time.
It’s been swelteringly hot (and only in the past week have I noticed it’s getting a bit cool at night and in the early morning), so I don’t think the temperature has anything to do with what’s happening to the trees. Someone told me this can happen when the weather is very dry too, because without enough water, the trees can’t produce chlorophyll, which is what makes them green. We’ve had little rain this summer, so perhaps this is the reason.