EF2 tornado in Bollinger County, Missouri

The tornado moved northeast across central Bollinger County, passing just north and west of Marble Hill. The most severe damage occurred in Glenallen (near Marble Hill), where several fatalities and injuries occurred. All five occupants of a demolished mobile home were killed there, including two teenagers, a middle-aged adult, and two older adults. Several manufactured homes were totally destroyed. Approximately a couple of dozen homes suffered major structural damage, including roof damage, broken windows, and collapse of walls. Severe tree damage occurred in the vicinity of Glenallen, where hundreds of trees were snapped at the base. A dozen or so farm outbuildings sustained major damage along the path of the tornado. Peak winds were estimated near 130 mph at Glenallen. The maximum path width and damage rating were assigned to the Glenallen area along Highway 34. The tornado was very close to dissipating when it crossed into Cape Girardeau County.

A cyclic supercell moved northeast from Arkansas, producing two tornadoes in southeast Missouri. Both tornadoes occurred in heavily forested areas. The second tornado struck a small community called Glenallen, located near Marble Hill in Bollinger County. Several fatalities were associated with this significant tornado. The supercell was the product of a favorable environment for tornadic storms. Moderate instability and strong deep-layer wind shear coincided over the region. Mixed-layer capes were between 1000 and 1500 j/kg in the presence of effective bulk shear around 55 knots. A surface low tracked from central Kansas into Iowa, resulting in a large unstable warm sector over Missouri and Illinois. Strong low-level south to southwest winds brought unseasonably warm late-night temperatures in the mid 70's and dew points in the 60's. The onset of storms was delayed by capping in the warm sector and pockets of dry low-level air. Wind fields strengthened throughout the night and capping weakened, leading to nocturnal supercell tornadoes.