This loop of GOES-8 visible imagery shows a lake effect cloud band over Lake Michigan during the morning hours on 04 October 1999. Rapid Scan Operations (RSO) was activated to allow this cloud feature to be monitored at 5 to 10 minute intervals. This cloud plume was producing light rain in some of the Chicago suburbs prior to 16:00 UTC. As the surface wind flow switched from northerly to southerly over the northern portion of Lake Michigan, the long fetch of cool low-level flow over the warm lake waters was disrupted; the cloud band over the southern portion of Lake Michigan became less well defined, and the light rain ended over parts of Chicago. Cyclonic eddy circulations could be seen over the central portion of Lake Michigan, where the winds were becoming light and variable.
This RSO imagery was also helpful to monitor the dissipation of valley fog over portions of the Mississippi River and central Wisconsin.