EF0 tornado in Sullivan County, Indiana

An EF-0 tornado tracked 4.10 miles over southern Sullivan County, between the Paxton and Carlisle communities. The maximum path width was 300 yards with multiple outbuildings significantly or completely destroyed and damage to trees. The supercell originally spawned two weak tornadoes in Crawford County, Illinois, which lifted before crossing the Wabash River into southwestern Sullivan County near Indiana Route 58. The tornado appeared to frequently come in contact with the ground at a few locations east of Route 58 but never remained in contact with the ground for a long distance, yet demonstrated damage that reflects high-end EF0 winds around 80 mph. The tornado maintained EF-0 intensity as it moved east-northeast through agricultural land, snapping a mix of large hardwood and softwood trees before lifting from Sullivan County. Damage was observed just northwest of Carlisle, where several small outbuildings sustained major damage. In this location, wind speeds were estimated at 80 mph, consistent with EF-0 intensity. The tornado continued across US-41 just south of Paxton, where the strongest damage, an additional outbuilding completely destroyed along with several large trees knocked over and snapped, was consistent with winds upwards of 85 mph; the storm survey estimates that the width of the tree damage spanned around 300 yards in an adjacent field. Peak wind speeds were estimated at 85 mph.

A strengthening storm system lifted through the Middle Mississippi Valley on the 19th, dragging its warm frontal zone northward through the Midwest, and bringing near-record high temperatures and anomalous dewpoints into central Indiana. Multiple rounds of severe weather occurred over the region, from early morning large hail in two far-northern zones, covering roads in Warren County, to more organized evening severe weather from rotating supercell thunderstorms. Through the evening of the 19th, the destabilized atmosphere combined with a stregthening low-level jet stream that progressed eastward into the region, boosting 0-1 km wind shear as high as 300 m2/s2. A resultant cluster of discrete late-day to evening supercells were focused along the frontal zone, near or south of the Interstate 70 corridor, and produced scattered large hail over 6 counties and isolated wind damage to trees and/or power poles in 4 counties.

A stronger supercell with a history of producing two weak tornadoes in Crawford County, Illinois, continued into central Indiana, spawning an EF-0 tornado in Sullivan County, an intense EF-2 just west of Bloomington that caused extensive structural damage to homes, apartments, and airport facilities, and a brief EF-U in Decatur County; this cell also produced ping-pong ball (1.50-inch diameter) sized hail in Greene and Monroe Counties.