2021 Monette–Samburg tornado
Throughout the evening hours of December 10, 2021, a large and destructive nocturnal tornado struck areas in and around the cities and communities of Monette and Leachville in Arkansas, Braggadocio and Hayti in Missouri, and Tiptonville and Samburg in Tennessee, killing eight people and injuring 16 others. The tornado was the second strongest and third deadliest of the tornado outbreak of December 10–11, 2021. The tornado reached peak intensity twice, the first time east of Braggadocio and the second time in Tiptonville, leading the National Weather Service to assign a rating of low-end EF4 on the Enhanced Fujita scale, with maximum wind speeds estimated at.
Early estimates suggested that the tornado family—identified by some media outlets as a "quad-state tornado", due to the storm's long track extending into Kentucky and its similarity to the tri-state tornado of 1925—might have cut a path of up to across the affected areas, making it the longest-tracked tornado in history. However, storm surveys found that the majority of the storm's path consisted of two distinct EF4 tornadoes – the Monette–Samburg tornado and the western Kentucky tornado – with three short-lived and weak tornadoes in between them in northwestern Obion County, Tennessee. The parent supercell that produced the two EF4 tornadoes, and eleven tornadoes in total, later became known as the "quad-state supercell".
Meteorological synopsis
On December 8, the Storm Prediction Center outlined a slight risk of severe weather across a broad area of the Mississippi Valley. Despite the potential for a higher-end severe threat to materialize, forecasters expressed uncertainty regarding the extent of instability, degree of directional wind shear, and late timing of potential storms. The following day, the SPC noted increased certainty of organized severe thunderstorm potential extending from southeastern Arkansas northeast into southern Indiana, thereby upgrading that region to an enhanced risk.As an intense upper-level trough progressed across the High Plains, with robust instability and moisture return realized across the Mississippi Valley, the SPC expanded the enhanced risk and introduced a moderate risk area from northeastern Arkansas into southern Illinois on the morning of December 10. Forecasters indicated that atmospheric conditions favored the development of nocturnal supercells capable of producing long-tracked, strong tornadoes.
At 3:00 p.m. CST, the SPC issued a tornado watch across the highest risk area, the first of eleven issued over subsequent hours over the middle Mississippi Valley. Initial storms developed across central Arkansas around 2:00 p.m. CST, with even weaker activity developing over central Missouri a little over hours later; additional clusters of thunderstorms developed over southwestern Missouri and central Arkansas between 5:00 and 5:30 p.m. CST. Though this activity lacked much vigor at its onset due to a strong capping inversion, the convective cells began to show organization as they progressed eastward.
One such storm—which formed from the initial mid-afternoon activity near Arkadelphia, Arkansas—matured into a long-lived supercell as it progressed in an unstable, deeply moist, and highly sheared environment; this cell ultimately persisted for longer than over several hours from eastern Arkansas to northeastern Kentucky, producing two large and intense tornadoes along its track, among eleven tornadoes in total. The fifth and first violent tornado produced by the storm was this tornado.
Tornado summary
Northeast Arkansas
The tornado first touched down in Craighead County, Arkansas, just north of Bay, at 7:07 p.m. CST on the evening of December 10, initially causing minor EF0 tree and outbuilding damage. As it moved through the south side of Bowman, it caused EF0 to EF1 damage as roofs were damaged, power poles and tree limbs were downed, and a radio antenna at a residence was bent. The tornado quickly intensified to EF2 strength as it crossed AR 18 and passed northwest of Lake City, downing trees and damaging or destroying some metal outbuildings. A house also sustained minor damage in this area and AR 135 north of the town was shut down due to downed power lines as well. It grew to a width of as it crossed County Road 505 and tracked to the northeast, snapping power poles and unroofing a house along County Road 508. Another house sustained major roof damage in this area, an irrigation pivot sprinkler was overturned, and a silo was damaged. The tornado reached low-end EF3 strength as it moved through the western and northern fringes of Monette at 7:23 p.m. CST, resulting in significant damage. Two industrial buildings were destroyed at the west edge of town, and many trees and power poles were snapped. The Monette Manor nursing home was struck by the tornado, killing one person and trapping 20 other residents and employees, including five people who were seriously injured. The building sustained major structural damage, losing much of its roof and sustaining the collapse of some masonry exterior walls. Multiple homes and mobile homes were damaged or destroyed in a neighborhood near the nursing home, and several large grain silos were torn apart. AR 139 was also shut down north of the town due to downed power lines on the roadways. Maximum wind speeds in the Monette area were estimated at.The tornado continued at low-end EF3 intensity as it crossed into northwestern Mississippi County, striking the northern part of Leachville at 7:30 p.m. CST. As the tornado crossed AR 77, it completely destroyed a local Dollar General store sweeping a portion of it off its foundation, killing the store's assistant manager. A few metal-framed warehouse buildings across AR 77 were badly damaged or destroyed, cars and semi-trailers were tossed, and multiple homes and mobile homes were damaged or destroyed in town. Extensive tree damage also occurred, and businesses in downtown Leachville had roofing blown off. Maximum wind speeds in the Leachville area were estimated at. The tornado continued northeast for and grew larger as it passed near the rural community of Buckeye, and very intense tree damage was noted along West County Road 38. An entire row of large trees was completely debarked and denuded at this location, and an EF3 rating was applied. The tornado also snapped power poles and destroyed an outbuilding in this area.