June 6-12, 2001

The week of June 6 to June 12 displayed promising signs of a return to summer in the Midwest. Light precipitation was widespread (Figure 8), but the heaviest precipitation was focused into two corridors cutting from west to east and from northwest to east across the region (Figure 9). Temperatures for the week were still a few degrees Fahrenheit below normal in the eastern Midwest, but were at or slightly above normal in the western Midwest (Figure 10). The week started cool and wet, especially north of a frontal boundary running from northern Missouri due east to southern Ohio. A series of two mesoscale convective systems moved from Missouri through to Ohio on June 6 and 7, bringing flooding rains to the northern two-thirds of Missouri, central Illinois, and central Indiana. The heavy rains in Illinois and Indiana were tightly focused into two west-east bands affected by training thunderstorms, and so the more diffuse gridded precipitation map belies the impacts on crops and communities in the affected areas in Illinois (Figure 11, NWS) and Indiana (Figure 12, NWS) that can be seen in radar accumulation maps. The town of Divernon, IL, near the state capital suffered $500 K in damage, with 5 houses severely damaged and another 20 partially damaged. A trailer park was also evacuated as trailers were flooded. Flash flooding was common in the affected areas. The largest impacts, though, were in northern Missouri, which had experienced heavy rains in the days leading up to the 6th. Not only did flash flooding affect dozens of counties, but many major rivers rose beyond flood stage (Figure 13, NWS). Along the Blackwater River and Grand River, floods crested more than 10 feet above flood stage. Even the mighty Missouri River came dangerously close to over-topping the levees protecting the airport and businesses in the flood plain across the river from Jefferson City, the state capital. The river crested at 30.27 feet, which is within inches of the height of the levees in question (Figure 14, USGS). Airplanes and rental cars had been evacuated, and businesses were packed and ready to evacuate, but this was the only financial impact at that location. However, thousands of acres of farmland were flooded along rivers where levee protection was lacking or insufficient.

After a few more days of nearly normal temperature conditions, the warm air finally pushed northward and eastward to bring normal summer conditions to all of the Corn Belt. Summer heat arrived by the 10th, and on the 11th, new record high temperatures were recorded in Mason City and Waterloo, IA. However, with the advent of heat and humidity, a severe weather outbreak affected much of the northern Midwest at the end of the period. Copious rains in Minnesota and Wisconsin with this system did not aid farmers, either (Figure 15, NWS).