Sounds like mid-September when the season opens here. I've hunted in hot/humid weather early in the season. One year it was in the upper 40s opening morning and I wore a sweatshirt. It felt COLD coming out of summer.

Delaware doesn't have a Spring squirrel season. Closest state that does is Virginia. I imagine the breeding window in DE is similar to VA, so hopefully they'll open a Spring season around here in the near future.