From June 20–26, 2023, a sequence of multiple severe weather events and tornado outbreaks began across large portions of the Great Plains, Midwestern, and Eastern United States as well as Manitoba and Ontario in Canada. This included a historic outbreak of 37 tornadoes in Colorado on June 21. A slow moving trough interacted with extremely high moisture and atmospheric instability to produce favorable conditions for supercells. Large hail and damaging winds accompanied a multi-day tornado risk which produced multiple strong tornadoes, including a destructive high-end EF3 tornado that killed 4 people in Matador, Texas on June 21, and another EF3 tornado south of Granada, Colorado on June 23. Multiple EF2 tornadoes touched down from Indiana to Kentucky on June 25. Reports of power outages, wind damage, hail damage, and tornadic damage accumulated across the affected region. In all, five people died from tornadoes, and three other non-tornadic deaths also occurred. Over 120 people were injured as well.
Meteorological synopsis On the heels of another tornado outbreak sequence, a new outbreak sequence began on June 20 with a few weak tornadoes in North Dakota and Manitoba. On June 21, strong southwesterly winds associated with a large upper-level trough over the Western United States began overspreading central portions of the country. The Storm Prediction Center (SPC) issued a bimodal level 3/Enhanced risk, one encompassing the tri-state region of Wyoming, Colorado, and Nebraska, and the second stretching from the Texas/Oklahoma panhandles into North Texas. To the south, an extraordinarily moist environment with dewpoints in the mid-70s °F over the spread area. High moisture combined with daytime heating resulted in an unstable airmass characterized by mixed-layer convective available potential energy (CAPE) in excess of 4,500 J/kg. Favorable wind shear overspread this environment, while the combination of outflow from morning storms and a nearby dry line became the focal point for thunderstorm development. A broken line of supercells developed from Kansas southward into Texas, contributing to large hail, damaging winds, and a few tornadoes. An especially intense tornado moved through western sections of Matador, Texas, killing four people and causing major damage. To the north across Colorado, Wyoming, and Nebraska, storms similarly developed along remnant outflow. Although low-level shear was weak, this outflow enhanced shear in the immediate vicinity of storms, resulting in numerous tornadoes that over largely open country. A total of 37 tornadoes touched down in Colorado that day, 27 of which were spawned by a single slow-moving supercell near Akron. A less active day occurred on June 22, although sporadic severe weather occurred across the Southern Plains, including a few brief tornado touchdowns in Colorado and Wyoming. This included a rain-wrapped EF1 tornado that moved through the Denver suburb of Highlands Ranch.
On June 23, the focal point for active weather shifted northward into eastern Wyoming and The Dakotas, where the SPC outlined a level 3/Enhanced risk. Stronger wind shear associated with an approaching shortwave trough overspread an unstable airmass with mixed-layer CAPE upwards of 2,500 J/kg. Through the afternoon, convection developed along the Laramie and Bighorn mountains, and along a warm front/outflow boundary across Wyoming and Nebraska. A few supercells evolved in this region, particularly later into the afternoon as low-level shear increased, producing large hail and numerous tornadoes, some of which were strong. This included an EF2 tornado that injured eight workers at the North Antelope Rochelle Mine in Campbell County, Wyoming. With time, outflow from ongoing convection merged, leading to a line of storms that pushed eastward. Farther south in southeastern Colorado and western Kansas, more isolated but significant supercells developed along a dryline and in an area of strong orographic lift. These highly structured cells moved east in a favorable environment, producing large hail and long-lived tornadoes, including an EF3 tornado that completely destroyed a farmstead near Granada, Colorado. On June 24, the risk area shifted deeper into the Midwestern United States. A low-pressure area tracked across southeastern North Dakota during the afternoon, supporting a warm front across northern Minnesota. Modest CAPE of 1,500 J/kg combined with strong shear along the boundary fostered low-topped convection and multiple tornadoes, including a strong EF2 tornado near Mahnomen, Minnesota. To the south, combined clusters of convection produced sporadic damaging winds across Iowa and Illinois.
An expansive level 3/Enhanced risk encompassed much of the Ohio River Valley and Mid-South on June 25. The greatest threat for potentially strong tornadoes was focused across Indiana, Ohio, and Kentucky. Here, the environment rapidly destabilized amid daytime heating, CAPE upwards of 2,000 J/kg, and the approach of an upper-level trough. An arcing band of supercells quickly developed by midday along a pseudo-dryline feature, producing very large hail and multiple strong tornadoes. To the north across Michigan, a line of convection in a more marginal environment produced sporadic damaging winds. Across the Southeastern United States, a moist and unstable environment devoid of strong low-level shear aided a long-lived mesoscale convective system that produced widespread damaging winds as well. Multiple rounds of linear convection contributed to additional severe reports through the evening. The threat for severe weather shifted eastward into the Mid-Atlantic on June 26, where the SPC issued a broad level 3/Enhanced risk stretching from The Carolinas into Pennsylvania and New Jersey. An area of low pressure moved across Michigan and supported a cold front across the Ohio River Valley. To the east, a pre-frontal trough also developed along the Blue Ridge Mountains. Mixed-layer CAPE of 1,000-2,500 J/kg and dewpoints in excess of across a wide region were forecast to materialize. However, diurnal heating was at least somewhat hampered by multiple rounds of convection and widespread cloudiness through the morning hours. Clusters of storms developed throughout the region ahead of the cold front, contributing to numerous instances of damaging winds and a few tornadoes as far north as Ontario until they began to weaken with the loss of daytime heating or pushed offshore beyond the coastline.
Confirmed tornadoes
June 20 event + List of confirmed tornadoes – Tuesday, June 20, 2023EF#LocationCounty / ParishStateStart Coord.Time (UTC)Path lengthMax width EF2ESE of Bayou GaucheSt. CharlesLA21:00–21:07A strong tornado was discovered via high-resolution satellite imagery. Widespread trees were uprooted and snapped. Ground scouring was noted as well. The tornado likely continued onto Salvador Lake before dissipating. EF1NNE of Carpenter, ND) to W of Lena, MBRolette (ND), Westman (MB)ND, MB02:35≥≥Aerial surveys revealed a tornado touched down just south of the Canada–United States border and moved northeast into Canada. Damage was confined to numerous trees that were snapped or uprooted. Only the Canadian portion of the track was surveyed. EF1NW of Killarney to SE of NinetteMB02:55A large tornado snapped trees and caused roof and siding damage to a couple of homes, one of which was shifted slightly off its foundation. A camper was tipped over, a quonset hut was destroyed, and several grain bins and barns were destroyed as well. EF1NE of MacGregorMB04:30Trees were snapped and several grain bins and farm outbuildings were damaged. A farmhouse had minor damage, and some metal storage tanks were dented.
June 21 event