F4 tornado in Massac County, Illinois

The tornado was near its maximum F-4 intensity as it crossed the Pulaski County line into western Massac County near the community of Hillerman. Estimated winds of 210 MPH disintegrated mobile homes and levelled several modern frame homes. One frame house was swept clean off its foundation, with only the roof left intact in a creek about 200 yards away. Many vehicles were lifted, rolled, or thrown up to 100 yards or more. Numerous cases of missiling were observed, including glass embedded in trees. Tree destruction in forested areas was nearly complete, and a few trees were debarked. The only fatality in Massac County was a 65-year-old female who was killed when her mobile home disintegrated. The official cause of death was blunt trauma to the head. She was found in a water-filled ravine about 100 yards from the former site of her mobile home. The frame of the mobile home was wrapped around the trunks of two trees that were stripped of all their limbs. Most of the levelled frame homes were concentrated on Boaz Road and Rolling Hills Road, in or near Hillerman. After passing through Hillerman, the tornado overturned dozens of railroad cars of a train just west of the Mermet Lake Conservation Area, which is off U.S. Route 45. The Mermet Lake Conservation Area was extensively damaged. An estimated 300 acres of forest were destroyed, boat docks were destroyed, and bathing facilities were destroyed. Dozens of waterfowl were found dead. After destroying additional residences and high tension power lines, the tornado crossed Interstate 24 near mile marker 28, about a mile south of the New Columbia exit. Tractor-trailer rigs and a tour bus were overturned on the interstate, injuring the drivers. The interstate was closed due to grain bins, tree limbs, and some building debris on the highway. Additional residences were destroyed between the interstate and the Pope County line. The tornado crossed into Pope County near where Illinois Route 145 crosses the county line. In Massac County, a total of 15 single-family houses and 13 mobile homes were destroyed. About 20 other single-family houses and 15 mobile homes received major damage. Several dozen other residences had some type of minor damage. Numerous vehicles and farming implements were destroyed, including combines. About 20 persons were injured in Massac County, but only one or two were hospitalized in serious or critical condition. Most of the injuries involved lacerations, bruises, broken bones, and internal injuries. Near Hillerman, a deputy sheriff escaped unhurt after his patrol car was thrown about 50 yards and struck by a flying tree and telephone pole.

The deadliest and most destructive storm of the night tracked within 10 miles of the Ohio River across extreme southern Illinois. The storm produced a 33-mile long tornado that killed two and injured about 33. A small but very damaging downburst occurred several miles south of the tornado track. A swath of large hail occurred north of the tornado track. Hailstones up to 2 inches in diameter were reported at and near the intersection of Highways 145 and 147, near the community of Glendale in Pope County.