The thunderstorms in the MCC weakened during the evening hours as the system moved into Iowa. In general, most of the storms produced only heavy rainfall and gusty winds. A few outbuildings were destroyed along its three mile path, which lasted six minutes. This MCC is typical of those which occur over much of the Midwest U.S. during the summer months. The thunderstorms within the complex are numerous and often produce very heavy rainfall, damaging winds, and hail.
Tornadoes do occur, but usually they are relatively weak in intensity.
From a satellite perspective, however, MCC systems appear quite ominous. The numerous thunderstorms inject large amounts of water vapor into the upper troposphere where it spreads out as a cirrus overcast over the entire active complex and often for many miles downwind. Being at a high altitude, the cirrus clouds are cold and appear as bright red on most color enhanced infrared images. The infrared image depicted in our gallery at 0901 UTC shows the MCC as the Galva IA F1 tornado, which lasted from 0355 CDT till 0401 CDT, was in progress. The image offers an example of the inherent limitations to satellite data in trying to determine tornadic thunderstorms from space-based platforms.