A major tornado outbreak took place between April 17 and 18, 2026, within the Midwestern United States, Upper Midwest, and the Southern Plains. The Storm Prediction Center forecasted a wind and hail-driven moderate risk for severe weather on April 17, covering portions of northern Oklahoma, central and eastern portions of Kansas, and western Missouri, with a risk for very large to giant hail, extreme damaging winds, and strong to intense tornadoes. Throughout the afternoon and evening hours, multiple tornadoes touched down in and around the risk area. Multiple houses were damaged and two people were injured by a high-end EF2 tornado that tracked through southern portions of Rochester, Minnesota. The town of Lena, Illinois was struck by a large high-end EF2 tornado inflicting significant damage. A low-end EF3 tornado tracked through areas near Cream, Wisconsin, causing significant damage to a home by removing most of its exterior walls and destroying several outbuildings. Another EF3 tornado struck portions of Ringle, Wisconsin, damaging and destroying around 75 homes and minorly damaging a school. Tornadoes in the Bloomington–Normal area heavily delayed two Amtrak trains as well.

Overall, 88 tornadoes have been confirmed during the outbreak.

Meteorological synopsis

Despite there being several rounds of thunderstorms in the day before this, a very unstable air mass was present over the Midwest extending down into Oklahoma. On April 15, 2026, the Storm Prediction Center outlined a Day 3 enhanced risk for much of Kansas, Iowa, Oklahoma, and Missouri, along with smaller portions of Illinois and Wisconsin, with all severe hazards considered possible. The following day, the enhanced risk was maintained, with the primary corridor for tornadic potential being located in southwestern Wisconsin, along with small parts of northeastern Iowa and southeastern Minnesota. This was driven by a CIG1 hatched 10% risk for tornadoes, later updated with a CIG2 hatched area being added in this update, with EF3+ tornadoes possible. This outlook was maintained into the next morning.

The next afternoon at the 1630 UTC Day 1 update, the SPC issued a Level 4/Moderate risk for severe weather in parts of Oklahoma, Kansas, and Missouri. Across the whole Enhanced risk area a very unstable air mass was present, extending from the Midwest down into Oklahoma, with dew points in the low 60's in Minnesota to the low 70's °F in Oklahoma and MLCAPE values reaching 3000 J/kg over Kansas into Iowa. In the Midwest, storms were expected to initially become supercells along a cold front and sweep east across Iowa, Minnesota and Wisconsin. As the sun set, the storms would merge into a squall line with a threat for damaging winds with brief tornadoes also likely across Illinois. Further south in the Moderate risk, supercells were expected to fire along a dry line near a triple point in Kansas and Oklahoma, but tornadoes were seen as less likely as winds were parallel throughout the atmosphere. However, giant hail (3-3.5" in diameter) and damaging winds up to 90 mph was still seen as likely.

Around 2 pm CDT, storms initiated along the entire line, roughly along I-35, with two Tornado watches being issued. However, a pair of supercells formed well ahead of the line in IA/IL/WI border in an environment marked with 100-200 m^2/s^2 of storm relative helicity (SRH) and produced multiple strong tornadoes in northern Illinois and Wisconsin, including an EF2 tornado near Lena, Illinois around 3:30 pm CDT and an EF1 tornado near Janesville, Wisconsin later after 5 pm CDT. Further north in Wisconsin, another cluster of supercells ahead of the line produced an EF3 tornado near Wausau, heavily damaging several homes. Along the main line, storms struggled to turn tornadic in Iowa, but over Minnesota a supercell was able to produce multiple EF2 tornadoes around Rochester and an EF3 tornado just across the Wisconsin border. Tornado activity across Iowa remained fairly limited with only four weak tornadoes confirmed despite the favorable environment, though large hail was common. In Kansas, another supercell also formed ahead of the front, but was unable to produce a tornado in the relatively unfavorable environment.

Around and after sunset, the line in Iowa began to congeal into a squall line and produce widespread damaging winds. Although MLCAPE values were lower, around 1500 J/kg, SRH values were increasing from around 200 to 450 m^2/s^2 thanks to the strengthening of the nocturnal low-level jet, and mesovortices formed along the line causing widespread tornadic activity. Over two dozen tornadoes struck Central Illinois, with multiple tornado warnings being issued, including for the National Weather Service office in Lincoln. Two EF2 tornadoes formed around 7:30 pm CDT around Table Grove and caused extensive tree damage. At 7:50 pm CDT, the first of two 30+ mile EF1 tornadoes touched town near Bluff City along the Illinois River and tracked nearly 37 miles, dissipating near San Jose. This mesovorticy went on to produce another EF2 tornado and an EF1 tornado that formed at 8:57 pm CDT and hit Normal while at the same time another EF1 tornado tracked through Bloomington. At that same time, the second 30+ mile EF1 tornado touched down south of Bloomington eventually impacting the city of Downs. Tornadoes continued eastward, but began to taper off as the squall line weakened. The last EF2 tornado touched down at 10:14 pm CDT and past south of Sheldon, snapping power poles as their base.

Further south along the line over Kansas and Oklahoma, storms did turn severe, but most failed to turn tornadic in the unfavorable conditions, though a couple still did occur. The supercells that formed in Kansas crossed over into Missouri and entered a more favorable environment and produced multiple weak tornadoes across the central part of the state.

Confirmed tornadoes

April 17 event