The 2007 Midwest flooding was a major flooding event that occurred in the Midwestern United States in the third week of August 2007. While Hurricane Dean was affecting the Yucatán Peninsula and the Gulf of Mexico, and Tropical Storm Erin was affecting Oklahoma and Texas, a persistent storm system hung over the Midwest for several days, causing repeated flash flooding in the US states of Illinois, Indiana, Iowa, Minnesota, Ohio, and Wisconsin. Cool Canadian air clashed with large quantities of warm moist air from the Gulf, producing torrential rains along a stationary front. 5 deaths across the central United States were attributed to the resulting flooding. Seven Minnesota counties, eight Ohio counties, fourteen counties in Wisconsin, and seven counties in Illinois were declared Federal Disaster Areas.

Tropical Storm Erin was a minimal tropical storm that made landfall in Texas in August 2007. The storm's remnants also unexpectedly restrengthened over Oklahoma, causing damage there as well. The second tropical cyclone to make landfall in the United States in the 2007 Atlantic hurricane season and the fifth named storm of the year, Erin formed in the Gulf of Mexico on August 14 from a persistent area of convection. It attained tropical storm status the next day, and on August 16, 2007, Erin made landfall near Lamar, Texas, and persisted over land across Texas before moving northward into Oklahoma. Due to the brown ocean effect, Erin intensified after landfall. The storm resulted in sixteen fatalities and worsened an already-severe flooding issue in Texas.