Not sure what part of Michigan you're in, but here in southern Macomb County I just saw the winged ants in our yard for the first time of the year yesterday - they are about a month later than they were in previous years. The little bit of rain and high humidity have caused them to come out.

I'm almost 100% willing to say these are NOT carpenter ants if they are in your yard. Carpenter ants don't usually nest in soil and usually only swarm earlier in the year. These are probably field or pavement ants.

The swarming is for the purpose of mating - the winged females that have mated will go off and form new colonies. An exterminator would be way overkill (hah) and the swarming will probably only last for a week or so, if even that. As long as they aren't invading your house, I wouldn't worry about it. When they are going insane where I've got my tomatoes planted, I'll sprinkle some diatamacious earth, but otherwise, I just pretend I don't even see them.

Thanks for this info. Ants are bad enough, but those wings really creeped me out. I didn't realize this was a seasonal thing. The ant granules I used did the trick and I didn't even need that much.