EF2 tornado in Williamson County, Illinois

An EF-2 tornado impacted the Lake Of Egypt community in the early morning hours of Tuesday, April 2nd. The tornado began near Highway 148, just west of Interstate 57, damaging limbs on several trees. Roof shingle damage and a snapped tree occurred on Teske Rd with tree trunks snapped on Whitecotton Rd and IL-37. After crossing IL-37 east of Interstate 57, the tornado passed along Lake of Egypt Rd, significantly damaging the roof of a home. The most severe damage occurred near the intersection of Lake of Egypt Rd and Market Rd, where severe roof and structural damage occurred to three businesses. The Lake of Egypt Fire Protection building nearby had one of its windows blown out. Paralleling Lake of Egypt Rd, the tornado did damage to homes and outbuildings before lifting just to the west of Wagon Creek Rd. Hundreds of trees were uprooted, snapped at the base, or suffered damage to large limbs along the path. Peak winds were estimated at 130 mph.

Early morning, the surface low was located just north of St. Louis, Missouri, lifting to the NNE as it rapidly deepened. For Southern Illinois, early morning effective bulk shear was 60-65 kts, with a very high 20-30 kts of 0-1 km shear, while SRHs near the Ohio River were around 150-200 m2/s2. MLCAPE was 1000 J/kg, and mid-level lapse rates were 6.5 C/km. A 70-90 kt mid-level jet was west of the Quad State. A strong capping inversion suppressed storm activity in the evening, but the strong lift and upper level diffluence won out early morning. Two lines of storms developed after midnight in Southeast Missouri. The first progressed through the I-64 corridor from 0100-0400 CST. The latter was a very potent thunderstorm line racing eastward early morning April 2nd. This line continued throughout the day all the way to West Virginia, being designated a derecho. For Southern Illinois, widespread wind damage occurred with this line, and sections of the line that took a north-south orientation had a much more favorable line-normal component of shear promoting QLCS tornado development. Seven tornadoes originated in Southern Illinois: 2 in Williamson County (EF-2 and EF-1), 1 in Saline County (EF-2), 3 in Gallatin County (all EF-1s), and 1 in White County (EF-2 with the EF-2 damage in Posey County Indiana). Two people suffered laceration injuries due to flying debris with the Saline County tornado. A total of 19 tornadoes were found during this event, the highest single day total for the NWS Paducah forecast area since Halloween 2003 (also 19).