We have Indian summer here as well. I think this warm spell (90s) is just summers last hurrah. We'll get indian summer when the leaves change.
We get Indian Summer sometimes, but, I think Fall is on time this year. The temp. today has been a refreshing 76 degrees (much better than the 100+ days we've had since about June-good riddance). There's a nice cool breeze blowing, and the light is starting to take on that soft quality it gets this time of year. Luv, luv, luv, it.