Treehugger, I didn't forget about you. I've been busy. But I think I found your moth. Here's a link to a Maryland site that says it's a Common Spring Moth (Heliomata cycladata). http://www.marylandbiodiversit...
There are some more links on that page if you want to read more. Also, BAMONA shows sightings in PA, as well. http://www.butterfliesandmoths...