What causes fog in the Midwest?

Fog in the Midwest is primarily caused by the combination of moist air and cool temperatures. When warm, humid air moves over cooler surfaces, such as lakes or farmland, it can lead to condensation and the formation of fog. Additionally, radiational cooling during the night can cause ground temperatures to drop, enhancing fog development. Factors like local topography and weather patterns also play a role in fog formation in the region.