The Way the World Works in Chicago

Lake Michigan acts as a funnel. Since migrating birds tend to follow shorelines, and since the lake forms a funnel bottoming out in northwest Indiana, the Chicago area can be very good for migrants. The best wind is a gentle northwesterly. That will blow the birds that might be inland up against the shoreline. Your birding along the lakefront on such a day can be very good. Similarly, if the wind is from the east, the birds are pushed back from the lakefront and you don't want to be along the lake in that kind of weather, particularly in the winter.

Probably the best place to be in Chicago during migration is along the lakefront.

Generally, in the winter, the most likely birds will be ducks (wherever there is open water) and gulls, particularly along the lakefront and in the Lake Calumet area. To find open water inland, look for dams. In the summer, most of the warblers have moved further north, although a few species nest in the Chicago area and some even nest in southern Illinois. There are few ducks or shorebirds around in the summer until migration starts up again in July.