Bev - I used to live in IN, and from memory, the best time to see the big silkworm moths was from mid-June to mid-July. You might have some luck at this time of year, but the odds are against it. Good luck anyway!
Tucker

There are still quite a few moths out. Some wait till this time of year to come out. You may see an ocasional tropical stray hawkmoth, but the silkmoths will probably all be gone. Some of the fall moths are quite colorful, mimicking the fall leaves. They will fly into November or when the evening temps are in the low 60's. Bait works well this time of year too.
Don

Catocala moths should be flying still.