Us too! (also in South Jersey) One very large Monarch butterfly flew through and inspected the milkweeds not 15 minutes ago. I was unable to determine if it was a male or female -- very flighty -- wouldn't let me get close, and I still have a hard time telling from underwing markings.
Since I haven't been able to find eggs, and I really think this was a he -- I thought the bands were on the thin side, but the size made me think Mama! I'll go double-check for eggs later when that part of the garden is in the shade.