@TheSeedObsesser - Great that you got to see them, maybe more will stop by. They have an odd migration pattern compared to many birds, but you are in their range for migration.
Great Egret.
We see them often in spring and summer, hunting in the swamps, and often on our pond. Many of them nest in the wildlife refuge just north of me (about 20 miles north of St. Paul). I hear them a lot in the woods behind my house, but I haven't ventured back there in a while. They are usually easier to photograph than a lot of birds, sitting so still watching for food to swim by. I hope you get to see them again ... with a camera!