I haven't seen any yet, but we had several folks at last Saturday's butterfly monitoring workshop report seeing mourning cloaks and eastern commas. In a case of very good timing, the latest edition of Chicago Wilderness Magazine has just appeared with an article by yours truly discussing early spring appearances by these very species.
Even though I haven't seen any butterflies here, I feel like I'm getting a taste of the early spring insect season. I just watched a sphinx moth attracted to the lights at my dining room window. It's hard to believe that tomorrow night the temperature is supposed to go down to 11°.