Dense Fog — Sheboygan, Wisconsin

2002-10-11 · Sheboygan, Wisconsin

Wider weather episode

Shallow dense fog developed over parts of Sheboygan and Ozaukee counties during the overnight hours, and persisted to about 0830CST. The dense fog, reducing visibilities to zero to 1/4 mile, was a factor in three closely-spaced, but separate multi-vehicle accidents in Sheboygan County (total of 50 vehicles), and one two-vehicle accident in northern Ozaukee County. In Sheboygan County, the three multi-vehicle accidents occurred around 0615 to 0620CST, on a stretch of Interstate-43 southeast of Cedar Grove. The southern-most of the three, involving 34 vehicles, resulted in 10 fatalities and 40 injuries. The interstate southeast of Cedar Grove is situated very close to Lake Michigan, where weak onshore flow of only 1-3 mph concentrated evaporated moisture off the relatively warm Lake Michigan waters. In that vicinity, the fog was especially dense, and newspaper articles reported that some drivers described the exceptionally dense fog as a whiteout, unavoidable, and unanticipated. Some drivers involved in the accident said they could look up and see blue sky, but couldn't see 5 feet in front of them. Additionally, law enforcement officials indicated that some of the drivers involved in the killer pile-up were probably driving too fast for the weather conditions. It is possible that sunlight at a low angle penetrating the shallow dense fog made visibilities worse due to scattering of light. Another two-vehicle accident occurred on the northwest corner of Belgium in northern Ozaukee county, resulting in 1 death and 1 injury.

Source: NOAA Storm Events Database, event_id 5319190. Narrative written by the NWS forecast office that issued the report.