How often does the Chicago get significant rain or other effects from the aftermath of hurricanes?
It’s not common, but Chicago occasionally gets rainfall fueled by moisture from landfalling tropical cyclones. Usually, the storm center has dissipated, but the residual moisture in the low and mid-levels of the atmosphere significantly boosts precipitation totals. On rare occasions, remnant low pressure from the dying tropical cyclone will move close enough to Chicago to bring both gusty winds and heavy rainfall. Though most of the systems affecting Chicago arrive via the Gulf of Mexico, occasionally moisture streams in from eastern Pacific systems. Severe flooding hit the Chicago area on September 12-14, 2008 when the combined moisture from Pacific Tropical Storm Lowell and Atlantic Hurricane Ike dumped 6 to 12 inches of rain.