December 2023 Tennessee tornado outbreak

A significant, late-season severe weather and tornado outbreak affected portions of the Southern United States, primarily across the states of Tennessee, Kentucky, and Mississippi. Tennessee was most affected by the outbreak, with multiple damaging tornadoes touching down, including a high-end EF1 tornado that damaged a National Guard Armory site near Dresden, a long-tracked, intense EF3 tornado that caused heavy damage in northwestern portion of Clarksville, and another strong, long-tracked high-end EF2 tornado that prompted a tornado emergency for the city of Hendersonville.

The tornadoes resulted in a total of seven deaths and injured 71 others, including 61 from the Clarksville tornado alone. The tornado outbreak scored 15 points on the outbreak intensity score, ranking it as a significant tornado outbreak. This system also caused significant winter storm impacts to the Northeastern United States.

Meteorological synopsis
On December 5, the Storm Prediction Center issued a 5-day severe weather risk ahead of predictions that strong convective instability and wind shear would occur across portions of the Southern United States, from east Texas to western Mississippi.

By December 7, a slight risk was posted in a large region from Louisiana to Kentucky. Uncertainties remained over the instability of airmass and the development of low-level flow conducive to tornado-inducing thunderstorms. By the next day, the slight risk was maintained for the same general area, and a 5% risk corridor for tornadoes was introduced for all of the northern sections of the main risk area, extending from extreme eastern Texas, south and southeastern Arkansas, northern Mississippi, northwestern Alabama, western and central Tennessee, and southwestern Kentucky. In this outlook, the SPC described the atmosphere and conditions as favorable for severe weather, as convective available potential energy (CAPE) values reached 500 J/kg in the main risk area, favorable low-level wind shear ahead of the expected upper-level trough, and moderate instability were all present to allow for sustained thunderstorm development.

On December 9, the outlook was maintained at slight risk up until 1630 UTC. In this last outlook, the main 5% corridor was enlarged to include portions of extreme northwestern Georgia, most of northern Alabama, and central portions of Tennessee, all the way to the Knoxville vicinity. Elevated dew points reaching 60 °F were expected to be present ahead of the passing of an advancing cold front, which, in combination with the aforementioned factors, created a very favorable atmosphere for severe weather. However, uncertainties in the extent of the tornado threat were still sufficient to avoid a categorical upgrade. The first area of concern that the SPC identified extended from southeastern Arkansas northeastward through portions of Mississippi, Alabama, and Tennessee into southwestern Kentucky. Within this area, tornadoes and large hail were expected to be the primary hazards with isolated supercells before the damaging wind potential increased as storm coverage increased. The first of what would be eight tornado watches during this event was issued shortly before this outlook, mentioning a moderate (60%) chance for tornadoes, and a low (20%) probability for strong (EF2+) tornadoes.

Clarksville, Tennessee/Allensville–Lickskillet–Auburn, Kentucky
This intense tornado formed approximately 5 mi south of Fort Campbell North, Kentucky in Montgomery County, Tennessee and moved northeast. After initially causing minor EF0 tree damage, the tornado quickly intensified to high-end EF1 intensity, completely destroying the Clarksville School of Fine Arts, inflicting heavy roof damage to homes and a church, and snapping several large trees. The damage to the school was rated high-end EF1, with winds estimated at 110 mph.

The tornado reached EF2 intensity as it passed just north of SR 374 and through multiple neighborhoods in the northwestern city limits of Clarksville. Numerous poorly anchored homes in this area were shifted off their foundations and leveled; many other homes had their roofs partially or completely removed; and hundreds of trees were snapped. One woman was fatally injured when her mobile home was destroyed, dying of her injuries a week later. The tornado then further intensified to high-end EF2 intensity, crested a hill, and entered a heavily wooded area where dozens of mobile and manufactured homes south of Britton Springs Road were obliterated, including some that were swept away with no debris left behind. Three more people were killed here, including a ten-year-old boy. Additional homes suffered partial to total roof removal, another poorly anchored home was shifted off its foundations and leveled, and hundreds more trees were snapped.

As it crossed US 41A in the community of Ringgold, the tornado briefly intensified to low-end EF3 strength with wind speeds up to 140 mph and destroyed a strip mall with only interior walls left standing. Vehicles in the strip mall parking lot were flipped over, several other businesses were also destroyed, a church lost its roof, and more trees were snapped. The tornado slightly weakened but remained strong at high-end EF2 intensity, flipping multiple 18-wheelers at a post office, inflicting significant roof and exterior wall damage to multiple well-built apartment townhouses, shifting and leveling more poorly anchored homes while inflicting severe roof and exterior damage to others, and snapping more trees. Continuing northeastward, the tornado crossed a wooded area surrounding Little West Fork Creek before strengthening to its peak intensity as it struck a subdivision just south of the West Creek High School. Four two-story brick and vinyl homes in this subdivision were completely leveled, with debris from the homes scattered 200 yd towards the northeast. All of these homes received ratings of EF3, with winds estimated at 150 mph. The National Weather Service noted that at this time, the tornado was “very narrow and intense,” and they also noted that the homes were partially screwed and anchor bolted to the foundation, with mostly nails being used as the foundation anchoring. Other two-story homes in the area had their roofs partially or completely removed, with exterior walls knocked down, including multiple homes that had their entire second floor removed. The nearby West Creek Elementary School sustained roof damage, and hundreds of trees were snapped as well.

The tornado then weakened slightly, but remained intense as it crossed Peachers Mill Road, where it struck an apartment complex at low-end EF3 intensity. Two dozen brand new, two-story apartment buildings were severely damaged, with at least a dozen of them having their roofs entirely torn off. Winds in this area were estimated to be at 140 mph. As the tornado continued towards the Tennessee-Kentucky border, it slightly weakened again, but remained strong, inflicting severe EF2 roof damage to dozens of homes in neighborhoods along Needmore Road and SR 236, and leaving behind cycloidal ground scouring in the fields between the two areas. The latter area also had several apartment or condo buildings sustaining high-end EF2 damage, along with at least two dozen steel electrical poles being bent. As the tornado crossed I-24 at the SR 48 exit, it uprooted numerous cedar trees and collapsed a portion of a warehouse. Northeast of the interstate, the tornado impacted several neighborhoods and subdivisions, producing widespread EF1 to EF2 damage to over 100 homes, many of which had roofs partially or totally removed along with some exterior wall collapse. Some additional tree damage also occurred before the tornado crossed into Kentucky In all, the tornado struck at least 1,000 homes and dozens of businesses in the Clarksville, Tennessee, area with at least 114 homes being destroyed, and 268 others sustaining major damage.

The tornado then moved northeastward into Todd County, Kentucky and over US 41 to the north of Guthrie at EF1 to EF2 intensity, snapping and uprooting hundreds of trees in rural areas. At least a dozen outbuildings were damaged or destroyed in the county, including a silo that was blown over and barns that were leveled, and homes suffered generally minor to moderate roof and garage door damage, although at least one home suffered severe roof and exterior damage. Just before crossing into Logan County, the tornado crossed US 79 and moved through the southern part of Allensville at EF2 intensity. At least 51 structures were struck by the tornado. Outbuildings were destroyed and homes suffered moderate roof damage up to partial removal. Debris from the structures was blown into farm fields as the tornado continued into Logan County. The tornado weakened to EF1 intensity after crossing into Logan County, damaging crops, trees, and outbuildings. It strengthened again to low-end EF2 intensity as it struck the community of Lickskillet, where every structure was damaged. A well-built two-story house in the town sustained extensive roof damage, had its foundation shifted, windows blown out, and three vehicles thrown and severely damaged. Two barns were also destroyed, with the impalement of barn boards into the home noted. The tornado then weakened back to EF1 strength as it moved further northeast, but continued to inflict severe roof damage to homes, damage or destroy outbuildings, and snap or uproot trees for several more miles.

The tornado then struck the community of Williams Store along KY 96 at EF1 intensity, damaging multiple homes and outbuildings, including one home that had parts of its middle section blown out. The tornado then continued moving northeastward at EF0–EF1 intensity, causing additional damage to homes and trees and damaging or destroying more outbuildings as it crossed US 431 and KY 100 south of Russellville. It then continued south of Auburn, where an outbuilding had its roof collapsed, and additional outbuilding, residence, and tree damage was noted. The tornado crossed into Simpson County, where it damaged the siding from an outbuilding roof before finally dissipating.

In total, the tornado killed four people and injured 61 others along its path of 47.76 mi while reaching a maximum width of 600 yd. 114 homes were destroyed (all of which were in Clarksville) while another 857 were damaged, and at least 20,000 people were without power after the tornado in Clarksville alone. The tornado also caused $45,000 in uninsured damage to the Clarksville School of Fine Arts. The school had been set to host a Christmas play on December 9 at 1:00 p.m. However, the play had been moved up to December 2, with 300 people in attendance. The director of the school later said “If we would have had 300 people in the building on the ninth instead of the second, we would be talking about the destruction of possibly hundreds of lives because there's nothing left of the theater.”

Madison–Hendersonville–Gallatin–Castalian Springs, Tennessee
This strong tornado was first observed by numerous storm spotters and residents at 4:39 p.m. CST (21:39 UTC) before tracking through areas of the Nashville metropolitan area. The tornado initially formed near Trail Hollow Lane, just to the east of I-24. It tracked east-northeast, causing minor EF0 damage to trees and residences. The tornado then quickly reached high-end EF1 intensity as it approached and crossed US 31W/US 41. Multiple outbuildings, a motel, and warehouses were heavily damaged or destroyed and multiple trees were snapped. Further to the northeast, additional damage occurred to residences, trees, and power lines as the tornado crossed Old Hickory Boulevard (SR 45), and I-65. As the tornado entered the north side of Madison, dozens of trees and power poles were snapped or uprooted, and numerous buildings, including businesses, warehouses, churches, and residences were damaged or destroyed at EF2 intensity. Three fatalities occurred when multiple mobile homes were destroyed in this area along Nesbitt Lane.

Before crossing US 31E, the tornado impacted an electrical substation, triggering multiple large power flashes and then an explosion when it impacted an oil reservoir. The explosion, as well as direct heat from the substation, caused a drop in relative humidity inside the tornado's condensation funnel, which, in turn, significantly reduced the tornado's visibility. The explosion was seen and captured on video by numerous residents inside the Nashville metro; it was also streamed live by a public live camera in Hendersonville. This was the first time a tornado had directly struck a Nashville Electric Service power substation since the 1974 Super Outbreak.

The tornado continued past the substation and crossed US 31E while maintaining EF2 intensity, heavily damaging or destroying homes and warehouses, and snapping or uprooting trees and power poles. The tornado continued northeastward and reached its peak intensity of high-end EF2 as it moved along and over the Cumberland River and Old Hickory Lake into the western part of Hendersonville in Sumner County. Hundreds of trees were blown down at the Old Hickory Dam, multiple buildings and warehouses at the dam site and a nearby marina were heavily damaged or destroyed; and a 75 ft microwave tower was crumpled to the ground. The tornado then weakened to high-end EF1 intensity as it approached and moved through the center of Hendersonville along US 31E. Heavy damage occurred throughout the town with multiple businesses at a strip mall reporting heavy roof damage with exterior wall collapses, several warehouses, other businesses, and outbuildings being heavily damaged or collapsed, homes suffering severe roof, siding, and exterior wall damage, and dozens of trees and power poles being snapped or uprooted. One two-story home in the area also had its entire roof removed, causing severe damage to the second floor's exterior walls. Past Hendersonville, the tornado caused more sporadic damage, mainly in the form of fallen trees and snapped power poles. Some homes and businesses suffered roof and siding damage, and a barn was heavily damaged with debris from the structure damaging a home. Two homes near the SR 386/US 31E interchange suffered heavy roof damage, with one of them also having its garage cave in. As the tornado approached Station Camp Creek, more homes, apartments, and condos were damaged, including another two-story home that had the second-floor roof removed, a gas station canopy was blown over, and more trees were snapped.

After crossing the creek, the tornado intensified as it moved into neighborhoods to the southwest of Gallatin from the southwest. Multiple well-built homes in the area suffered partial to complete roof removal; other homes suffered minor to moderate roof damage; trees were snapped (including at least one that fell on a home); and a metal truss tower was collapsed. Damage in this area was rated high-end EF1 to EF2. The tornado weakened to EF1 intensity again, but continued to cause heavy damage to homes as it moved through the southern part of Gallatin and crossed SR 109. Several homes had their roofs partially or totally removed, and many trees and power poles were knocked down. Warehouses at the nearby Music City Executive Airport were also heavily damaged, and more homes northeast of there had varying degrees of roof damage, with another home having its roof removed, along with more down trees. The tornado then passed just south of Cairo, heavily damaging an old barn country store along SR 25, knocking down trees, and inflicting minor damage to outbuildings. It passed north of Castalian Springs. It then continued into Trousdale County, inflicting one last area of EF1 damage to trees near Templow before it dissipated northwest of Hartsville.

The tornado killed three people and injured another three along its 35.27 mi path that reached a peak width of 600 yd. The substation in Madison supplied 161,000 volts to a DuPont Plant in Old Hickory, while the one in Hendersonville served power to customers, though it was in need of repairs.

Non-tornadic effects
A winter storm in relation to the system closed I-29 from Fargo, North Dakota to the Canadian border from Manitoba.

Strong storms affected the Northeastern United States on December 10–11. The heaviest rain in the New York metropolitan area was on Long Island, where over 4 in of rain fell in certain areas. High winds were also reported, with gusts reaching 48 mph in Kew Gardens and 46 mph in Orient. Light backend snow was observed in Sullivan County. Nearby, the highest snowfall of 13.7 in was in Roxbury, New York. The storm resulted in ground delay programs at LaGuardia Airport and John F. Kennedy International Airport. Parts of New York State Route 25 closed during the floods, as did the eastbound lands of the Belt Parkway. Parts of Connecticut saw rainfall exceed 5 in.

On December 10, daily rainfall records were set in Philadelphia, Atlantic City and Wilmington. The storm resulted in a brief stretch of I-76 shutting down in Montgomery County following a downed tree and a 3-way car crash. Further south, light snow at Dulles International Airport accumulated 0.4 in, but that was more snow then what fell during the entirety of the previous winter. 0.1 in of snow was recorded at Ronald Reagan Washington National Airport. Richmond, Virginia received their first measurable snow since March 12, 2022.

Aftermath
Singer-songwriter Taylor Swift donated $1 million to the Tennessee Emergency Response Fund at the Community Foundation of Middle Tennessee in support of tornado victims.