 Several waves of thunderstorms associated with a slow-moving warm front produced unusually heavy rainfall throughout the region beginning in the early afternoon of September 22 and continuing until the evening of September 23.Tropical moisture moving northward from remnants of tropical storm Georgette in the eastern Pacific and Hurricane Karl in the Gulf of Mexico contributed to heavy rainfall.The highest rainfall reported for the two-day period in Minnesota was , recorded by a volunteer observer near Winnebago in Faribault County.