An unusually warm and humid air mass pushed into central Illinois on March 10, sending temperatures soaring into the upper 70s and low 80s and setting several records.
According to the National Weather Service, new record highs were recorded in several cities, including Springfield at 84 degrees, Peoria at 83 degrees, and Lincoln at 82 degrees. Each of those marks broke previous records that had stood since 1955.
The warm conditions helped fuel a volatile atmosphere later in the day. A stationary front stretching from Iowa into Indiana created a sharp temperature contrast across the region, helping set the stage for severe weather.
Storms were slow to form during the afternoon, but activity ramped up later in the day as weather conditions became more favorable.
The first severe thunderstorm developed near the line between McLean County and Woodford County. The storm initially produced quarter-size hail before strengthening as it moved northeast.
Near Pontiac in Livingston County, the storm dropped destructive grapefruit-sized hail — more than four inches in diameter — before producing a long-track tornado in Kankakee County that continued into northwest Indiana.
Additional storms developed farther west along the same weather boundary. A few of those storms moved across Knox County, Stark County, and Marshall County, where several funnel clouds were reported. Two brief EF-0 tornadoes were later confirmed in Stark and Marshall counties.
Another round of storms developed around midnight as a cold front approached the Mississippi River. One storm produced a powerful downburst in Havana with winds estimated between 80 and 90 miles per hour.
Shortly after, the storms intensified again and produced two EF-1 tornadoes. One tornado tracked from east of Havana toward Topeka, while another moved from south of Forest City to south of Green Valley.
The tornadoes snapped trees and power poles, overturned irrigation systems, and partially destroyed a horse barn.
Storms continued moving through eastern and southeastern Illinois overnight, producing scattered wind damage, heavy rainfall, and frequent lightning before finally weakening.
