A funnel cloud was seen from a shower in Steward, Illinois Sunday evening, July 5, 2009. This funnel cloud came out of a the base of a shower that was moving through Steward around 6:30 pm CDT. Here are some pictures of the funnel courtesy of WREX TV in Rockford, Illinois.
The first picture shows the funnel cloud and the second is a close up of the funnel cloud. The next image is a reflectivity image of the shower that produced this funnel cloud. The time of the image is 23:38 UTC or 6:30 pm CDT as the shower was moving just south of Steward. The shower was small and along a surface boundary of cooler air. The yellow arrow points to the shower.
The darker blue reflectivity color indicates a boundary. This is a front where cooler air is colliding with warmer air. Sometimes there is enough wind change along these boundaries that the wind develops a spin. This spin could be ingested in the updraft of a shower and the result is a spinning updraft that could produce a weak funnel cloud.