EF1 tornado in Wayne County, Illinois

This tornado began in extreme eastern Wayne County about one mile from the Edwards County line. The peak intensity rating in Wayne County was EF-1, but the tornado strengthened to EF-2 in Edwards County. In Wayne County, damage was mainly to trees, many of which were snapped or uprooted. The tornado moved into Edwards County. This tornado was spawned by the same supercell that produced the EF-2 tornado that tracked from Sims to Fairfield in Wayne County.

Supercell thunderstorms developed along a pre-frontal low pressure trough over Missouri and then moved east across southern Illinois. Very strong wind fields coupled with moderate amounts of instability resulted in several supercell thunderstorms, some of which produced tornadoes. The storms moved through the warm sector of a low pressure system characterized by mixed-layer capes around 1000 j/kg. Southerly surface winds transported rich low-level moisture north of the Ohio River, with dew points in the mid 60's. Areas of partial sunshine immediately preceding the convection bolstered instability. The low level wind shear was very strong, with 0 to 1 km storm-relative helicity at or above 500. Strong southerly surface winds ahead of the storms gusted to around 45 mph from Mount Vernon to Carbondale during the midday hours.