Above is the 11-3.9 Low Cloud/Fog product from1101Z that shows an extensive area of stratus and fog over portions of Lower Michigan and Southern Lake Michigan.
The GOES R IFR probability from 1115Z shows over 80% probability of IFR ceilings over much of Lower Michigan and parts of Southern Lake Michigan. While surface obs can tell a forecaster the IFR ceilings over land, the GOES R product adds confidence that IFR conditions with stratus and fog were occurring over lake Michigan.
Below the Visible image from 1515Z confirmed the existence of fog and stratus over Southern Lake Michigan. The GOES R IFR probability showed values of IFR ceilings over 40% over much of the Fog/stratus layer over Lake Michigan. There is uncertainty on whether this is fog or stratus, but web cam images showed mainly fog. The GOES R IFR probabilities are lower over Southern Lake Michigan during the daytime.
Steve Hentz
WFO MKX
WFO MKX