From June 9–11, 2026, a major tornado outbreak and associated derecho occurred across the Central and Midwestern United States and southern portions of Canada, causing significant damage in its wake. The Storm Prediction Center (SPC) first issued an enhanced risk of severe weather on June 9 for the regions of North and South Dakota as well as Nebraska, though only a few tornadoes occurred, including an EF3 tornado that touched down near Oxbow, Saskatchewan, severely damaging a farmstead. Continued activity occurred on June 10 with multiple tornadoes occurring across Missouri and Iowa, including an EF2 tornado that caused significant damage to rural areas near Unionville, Missouri.

The bulk of the activity took place on June 11, where the SPC issued a moderate risk of severe weather with a heightened chance for strong tornadoes. The states of Illinois and Indiana saw multiple long-lived and intense tornadoes touch down. In Illinois, a large EF3 tornado demolished a log home, severely damaged numerous trees, and triggered a tornado emergency for Toluca. Another EF3 tornado struck eastern portions of Streator, damaging dozens of residences and injuring seven people, and a long-tracked EF1 tornado moved across rural areas near Dwight, inflicting damage to multiple structures.

Later that afternoon, an EF2 tornado tracked through Merrillville, Indiana, damaging hundreds of structures and injuring one person. A high-end EF3 tornado, the strongest of the outbreak, traveled near Kouts, Indiana, completely destroying multiple homes, severely damaging trees, and shearing transmission towers from their bases. An EF2 tornado significantly damaged several apartments and injured six people after tracking through Bridgeview, Illinois, and one person was injured after another EF2 tornado inflicted significant damage to homes in Elkhart, Indiana.

Accompanying the tornado outbreak was a significant derecho event that traveled more than across the states of Iowa, Wisconsin, Illinois and Indiana on June 10, producing wind gusts well over and causing significant damage. Combined, the two events caused more than 264,000 customers to lose power at the height of the storms.

During the three-day period, 102 tornadoes touched down across nine US states and two Canadian provinces, injuring 17 people and causing significant damage. Additionally, three people were killed due to being struck by trees that were downed by straight-line wind.

Meteorological synopsis June 9 On June 4, the Storm Prediction Center outlined a 15% probability of a severe thunderstorm within of a point for June 9, with the area covering a large portion of western North Dakota, stretching from the northern state border to the southern one. A mid-level trough was likely to be draped over the western US, with an area of stronger upper-level winds moving across the Northern Plains. A low-pressure system was expected to strengthen over the northern High Plains, with a trough stretching from the central to southern High Plains, and along with low-level convergence, supported the development of severe thunderstorms.

On June 5, the Storm Prediction Center expanded the 15% severe weather area to include more of North Dakota, encompassing most of the central part of the state, along with a narrow portion of northern South Dakota. A short-wave trough with a mid-level jet streak extending from the base were expected to develop, along with a strengthening low-pressure area over the northern High Plains, with the low moving into the Dakotas by June 10. Alongside the low-pressure area, a Pacific or cold front was expected to move from the Rockies, with ample atmospheric moisture and sufficient wind shear forecasted to be present ahead of the low-pressure area and front, creating an environment conductive to the formation of severe weather.

On June 6, the 15% severe weather area was significantly expanded, enveloping nearly all of North Dakota, a slim portion of western Minnesota, and a large portion of central-northeastern South Dakota. The low-pressure area was expected to form over western North Dakota before moving over eastern Minnesota by the afternoon. The warm sector ahead of the low-pressure area and front was expected to have steep low and mid-level lapse rates, and along with dew points around , supported the development of thunderstorms during the later afternoon and evening hours of June 9. Intensifying vertical wind shear and associated jet streaks were expected to favor the formation of supercells capable of producing large hail and strong winds, with a tornado threat being possible in the late evening when the low-level jet streak strengthens, increasing low-level wind shear.

On June 9, a low-pressure system that formed over Montana was expected to move east-northeastward and pass over portions of southeastern Saskatchewan, southwestern Manitoba, and northwestern North Dakota during the afternoon hours. Isolated storms were forecasted to form in southwestern portions of Manitoba, bringing a threat for hail and tornadoes. Additionally, linear storms were expected to develop along a cold front or dry line across Saskatchewan and North Dakota later in the evening and track quickly to the east, potentially meeting the criteria to be classified as a derecho.

June 10

An enhanced risk of severe weather was issued on June 10 for parts of the Upper Midwest, including a risk of strong tornadoes. Later, a large, long tracked EF2 tornado struck near the town of Unionville, Missouri. This storm was tagged with multiple PDS tornado warnings.

June 11

The first instance that a severe weather event was possible for June 11 was evident four days earlier on June 7, when the Storm Prediction Center (SPC) highlighted a 15% risk of severe weather over the lower Great Lakes and Midwest, citing a shortwave trough expected to move through the region. It was upgraded to a 30% risk of severe weather the following day from northeastern Missouri through the northern half of Illinois, citing increased confidence. On the Day 3 outlook at 07:30 UTC on June 9, an enhanced risk was issued by the SPC for Missouri to western Michigan, as an unseasonably strong 500-mb jet with mid-level winds near was expected to be present. The evolving question regarding tornadic potential was whether the airmass over the risk area would recover enough and destabilize sufficiently following a mesoscale convective system (MCS) that was expected to pass through the risk area during the morning hours of the event.

On June 11, the risk was upgraded to a moderate (4/5) risk of severe weather during the 1300z outlook cycle. This was driven by a risk of tornadoes with a 15% risk contour and CIG2 hatching, denoting a probable max tornado intensity of at least EF3, and a risk of straight-line winds with a 60% risk contour and CIG 1 hatching. As the shortwave approached, a low-level jet in excess of were expected to intensify to coincide with the destabilizing atmosphere in the maximum risk corridor, which would allow for supercells to develop along the advancing cold front of the parent system. Tornadic activity began later that evening. A tornado emergency was issued for Toluca, Illinois due to a large wedge tornado, rated EF3. That same supercell would eventually spawn another EF3 tornado that hit the south-southeastern parts of Streator, where at least four people were injured. A damaging EF1 tornado touched down in Dwight but missed most structures in the path. A low-end EF2 tornado impacted Merrillville and Hobart, Indiana, prompting a PDS Tornado Warning. An EF1 tornado touched down near Hebron prompting another PDS tornado warning, followed by a high-end EF3 tornado touching down in Kouts.

Confirmed tornadoes

Wilbern–Washburn, Illinois

This large and intense tornado first touched down at 4:56 pm CDT in Woodford County, just north of Banta Road and to the east of the Illinois River, uprooting and damaging trees at EF1 intensity. The tornado tracked northeastward, mainly damaging trees over forested areas before tracking over Bricktown Road, where it impacted several outbuildings, including one that was completely destroyed. The tornado turned more to the east, crossing Dry Creek and tracking along Columbia Road to the south. An outbuilding had its walls collapse, and various trees were snapped and damaged. The tornado crossed Columbia Road just to the west of the Columbia Road/County Road 810 East intersection, where a home had several windows shattered. Power poles along Columbia Road were snapped, and several hardwood trees were damaged at EF2 strength. The tornado continued northeastward, damaging and removing the roofs from a single-family home and two mobile homes before destroying another outbuilding. The tornado turned more to the north as it crossed Washburn Road, damaging a home and hardwood trees at EF2 intensity. A nearby corn field suffered extensive crop damage. The tornado tracked through rural areas, crossing Snag Creek and entering Marshall County as it caused EF1 damage to various trees. The tornado then tracked across the Pleasantview Road/Snag Creek Road intersection, damaging homes and outbuildings, with one mobile home having its entire roof structure removed. The tornado continued to track northeastward, crossing Pleasantview Road for the second time as it collapsed another outbuilding and damaged the roof of a mobile home. A Ford F350 in the area was tossed approximately . The tornado tracked just south of Pleasantview Road, inflicting EF2 damage to a home on the northern side of the road before crossing it once again.

The tornado tracked just north of Pleasantview Road, snapping hardwood trees at EF2 intensity. The tornado inflicted EF1 damage to a residence. To the north of this home, numerous trees were snapped and damaged, including several hardwoods that were stubbed and debarked at mid-range EF3 intensity. The tornado continued inflicting EF3 damage to trees as it crossed another road just north of Pleasantview Road. The tornado continued tracking northeast, damaging a grove of trees at EF2 strength before striking a log house at peak intensity southeast of Wilbern. This newly built, well-anchored log home had all its walls collapsed, with several exterior walls being pushed off the foundation. The structure lacked steel beam support throughout the construction. A nearby flag pole was bent at the base, a large propane tank that was completely filled was tipped over, and a car was tossed to the east of the garage. The tornado's maximum wind speeds of were estimated at this location. The tornado weakened before crossing County Road 100, where a home sustained EF2 damage and an outbuilding was destroyed. Power poles along the road were snapped, and nearby trees sustained significant damage. The tornado maintained EF2 intensity as it struck another home, tearing off the entire roof and attic structure. Another outbuilding was destroyed, and more trees were damaged. The tornado continued to the northeast just north of Washburn, snapping power poles along Tax School Road and inflicting EF1 damage to various trees. As the tornado crossed IL 89, it bent steel poles at EF2 intensity before impacting a solar farm, with numerous solar panels being damaged. Around this time at 5:11 p.m. CDT, a tornado emergency was issued for Toluca, Wenona, and Varna as the tornado continued to track northeastward. The tornado tracked just south of County Road 150 North, dissipating right before crossing the road at 5:15 pm CDT. The tornado traveled for and reached a maximum width of .

Long Point–Ancona–Streator, Illinois