This has little to do with bonsai.

It has been hot here by anybody's standards. For well over a month, humidity always over 80%, usually over 90%. Temps were usually highs around 100F/38C and lows 88F/31C. Sometimes as high as 105F/41C.

Fall may be on the way, highs last week and projected next week 86/30, lows 63/17. All of a sudden there are leaves turning yellow and falling. The yard doesn't look like November, but the trees are dropping them.

What's going on?

In the past the trees have experienced frost around mid November, so you can't call us tropical. Last year was warmer than usual, like everywhere. This year, who knows?