On February 10–11, 2009, a broad-scale damaging wind event and small tornado outbreak affected the Central and Eastern United States. During the two-day period, 14 tornadoes touched down in seven states. Oklahoma was struck by six tornadoes, the most of any state. The six tornadoes in Oklahoma also tied the record for the most tornadoes ever recorded in the state during the month of February, which would later be broken in 2023. The first day of the outbreak produced the most tornadoes; the second brought mainly high wind damage and rain or snow in most of the Northeast.
The storm system responsible for the tornado outbreak resulted from the unusual congruence of a cold, dry system, originating in the Four Corners and a warm, moist system, moving north out of Texas. Complicating factors included daytime heating and a strong wind field favorable to the creation of circulating thunderstorms. On the second day, the stronger cold front limited discrete supercell activity and the risk of tornadoes decreased significantly. A squall line, however, produced high winds and rain along the river valleys, primarily those of the Mississippi and Ohio Rivers. A tight pressure-gradient behind the cold front led to a large area of damaging non-thunderstorm winds across the Midwest and Ohio Valley. This squall line continued to renew its energy as it passed through the Midwest, Pennsylvania, New Jersey, New York, and New England, causing wind and water damage, and dumping of snow in central and eastern Massachusetts. The resulting power outages affected homes throughout the northeastern seaboard.
The widespread damaging winds left an estimated $1.7 billion (2009 USD) in damage across the Ohio River Valley and Southeastern United States. A small tornado outbreak accompanied the storm, with 14 confirmed across 7 states. The most significant damage occurred in Oklahoma from two tornadoes in the Oklahoma City metropolitan area and a deadly EF4 tornado that destroyed large parts of Lone Grove. The EF4 tornado killed eight people and injured 46 others.
Meteorological synopsis February 10 Early on February 10, 2009, a strong upper-level trough moved east from the Four Corners into the central and southern Great Plains by the afternoon and early evening hours. Temperatures across Texas and Oklahoma were unusually low antecedent to a severe weather outbreak, generally ranging from . Early morning fog moving northwest into Oklahoma signaled the arrival of low-level moisture into the region. Strong surface heating combined with cooler air aloft created an unstable atmosphere, a situation unusual in the region for February. In the afternoon hours, a shortwave trough moved from Arizona into Texas while a strong mid-level jet emanated from the Big Bend region. Daytime heating of the moistening boundary layer increased throughout the afternoon across Oklahoma and Texas as cloud cover shifted eastward. A very strong wind field increased with height through the lower troposphere, resulting in a wind shear favorable for rotation in the thunderstorms.
Meteorologists expected large hail stones and damaging winds, and recognized the potential for strong tornadoes as thunderstorms developed from central Oklahoma southward into north-central Texas in the afternoon. During the night, a cold front moved eastward toward the Mississippi Valley and organized the thunderstorms into a lengthy squall line. Along with a continued threat of hail and tornadoes, the risk of damaging winds increased. The Storm Prediction Center announced a "moderate risk" of severe weather for portions of eastern Oklahoma, northeastern Texas, western Arkansas, and northwestern Louisiana.
Around 19:00 UTC, a line of thunderstorms began developing near the Wichita Mountains in Comanche County, Oklahoma. One supercell originating there produced five tornadoes from Canadian County in the Oklahoma City metropolitan area to Pawnee County. One of these was rated EF2 when it struck western areas of Edmond. The most significant tornado originated in Montague County, Texas at 00:48 UTC. It quickly crossed the Red River into Oklahoma and moved through predominantly rural areas, ultimately striking Lone Grove at EF4 intensity. Severe damage took place in the town and eight people were killed.Lone Grove, Oklahoma, EF4 tornado NCEI references:
In addition to the five Oklahoma tornadoes, three tornadoes struck northern sections of Texas and one tornado hit Springfield, Missouri.
February 11 Concurrent with the strong upper-level trough tracking northeastward, the threat for organized severe weather shifted eastward into the Ohio River Valley on February 11, where the Storm Prediction Center issued a Slight risk across much of the region. Very strong wind fields, including mid-level winds upwards of , overspread the risk area. Strong forcing along an eastward-moving cold front combined with those wind fields led to the persistence of a low-topped squall line despite little instability ahead of the convection. Widespread sunshine developed ahead of the squall line throughout the afternoon hours, increasing the potential for strong winds aloft to be transferred to the surface. As such, the Storm Prediction Center raised the threat level to a Moderate risk across portions of Kentucky, Ohio, and West Virginia for widespread and potentially significant damaging winds. The organization would ultimately receive over 350 reports of damaging winds on February 11, including a peak gust of near Belle, West Virginia. By the evening hours, the squall line encountered cooler surface temperatures and became increasingly separated from the powerful upper-level trough, and it lost its vigor moving through the Mid-Atlantic region.
Confirmed tornadoes + Daily statistics of tornadoes during the outbreak of February 10–11, 2009 DateTotalEnhanced Fujita scale ratingDeathsInjuriesDamage EF0 EF1 EF2 EF3 EF4 EF5 February 1010 2 6 1 0 1 0 850 February 11 4 1 3 0 0 0 0 0 0 Total 14 3 9 1 0 1 0 850
February 10–11 event + Confirmed tornadoes during the tornado outbreak of February 10–11, 2009EF#LocationCounty / ParishStateCoord.DateTime (UTC)Path lengthMax widthSummary EF1NNW of Wiley Post AirportOklahomaOK20:36–20:37This was the first of five tornadoes produced by a supercell in northwestern areas of the Oklahoma City metropolitan area. This brief tornado touched down in a large shopping center along SH-3 and caused extensive roof damage to several structures. It then moved into a residential neighborhood where several buildings in an apartment complex saw primarily minor damage; one apartment had its roof torn off. EF2Western EdmondOklahoma, LoganOK20:53–21:05The second tornado touched down on the west side of Edmond and traveled northeast into Logan County. Extensive damage occurred in residential areas, with the most severe damage occurring in the Oak Tree development along the Oklahoma–Logan county line. There, several homes had large portions of their roof torn off and garages destroyed. An auto body repair shop and mobile home were totally destroyed. Throughout Edmond, six homes were destroyed, eight structures received major damage, 51 received minor damage and another 166 structures were affected. Approximately 28,500 people lost power, primarily in the Edmond area. Hundreds of trees were uprooted or significantly damaged along the tornado's path. In Oklahoma County, the tornado left an estimated 28,500 people without power. Four people suffered minor injuries.Edmond, Oklahoma, EF2 tornado NCEI references: The combined damage of the two Oklahoma County tornadoes was estimated at $10.2 million. EF1NW of MeridianLoganOK21:24–21:26A brief tornado tore the roof off one home and damaged the roof of another. Minor tree damage occurred. EF1ENE of Langston to SW of StillwaterPayneOK21:39–21:59This tornado destroyed a barn and an oilfield communications tower and snapped trees. Numerous power lines and transmission poles were brought down near an Oklahoma Gas & Electric substation, leaving 1,586 customers without power in Payne County. Most of the outages were around SH-33. EF0SSW of PawneePawneeOK22:35–22:37Two barns were completely destroyed and several homes were damaged. Power poles were also damaged but service was restored within a day. Four cows presumed to have been "blown away" from a pasture. This was the last of five tornadoes produced by the Oklahoma metro supercell. EF0Southern BelchervilleMontagueTX00:25–00:28A brief tornado destroyed several outbuildings and two sheds and damaged the roof of one home. Two trees were uprooted and a water tank was flipped. The storm that produced this tornado later spawned the EF4 Lone Grove tornado. EF4S of Spanish Fort, TX to Lone Grove, OK to SSE of Springer, OKMontague (TX), Jefferson (OK), Love (OK), Carter (OK)TX, OK00:45–01:438 deaths – See article on this tornado – 46 people were injured. EF1ColleyvilleTarrantTX03:15–03:17This brief tornado touched down in the northwestern suburbs of the Dallas–Fort Worth metroplex. Damage was confined to the Caldwell Creek neighborhood where 5 homes had extensive roof or structural damage and 15 others suffered minor damage. Monetary losses were estimated at $750,000. The American Red Cross provided supplies and snacks to residents. EF1Southwestern SpringfieldGreeneMO04:43–04:49This tornado moved along an intermittent path across southwestern and central Springfield, damaging one to two dozen houses and businesses, and toppling several trees and power lines. At least 250 residences were left without power, and damage was estimated at $350,000. The tornado occurred without being detected on radar until it had already touched down. 1A 4A EF1NNE of Garden ValleySmith, WoodTX05:16–05:25A barn was destroyed and several metal buildings were damaged or destroyed northwest of Lindale and several homes near Mineola were damaged by fallen trees. Damage from the tornado was estimated at $400,000.Garden Valley, Texas, EF1 tornado NCEI references: EF1SW of KeachiDe SotoLA07:04–07:06A metal barn was destroyed, two homes suffered minor damage, and trailers were flipped over. Many trees were snapped or uprooted. EF1SSW of ClarkrangeFentressTN19:03–19:04A brief tornado snapped or uprooted dozens of trees, two of which fell on vehicles and one on a home. One home had part of its roof torn away. EF1E of MedfordDelawareIN20:30–20:31A brief tornado damaged the roof of a barn and home. EF0Honaker areaRussellVA22:59–23:02This weak tornado knocked over several trees and damaged one barn.
Spanish Fort, Texas/Lone Grove–Ardmore, Oklahoma
The strongest tornado of the outbreak touched down as a multiple vortex tornado just south of Spanish Fort in Montague County, Texas initially snapping pecan trees. As it crossed the Red River of the South along the Texas-Oklahoma border, the tornado consolidated into a large funnel and tracked through the predominantly rural farmland of Jefferson, Love, and southwestern Carter counties, producing tree damage in all three; two homes were damaged in Love County. In central Carter County, the tornado reached low-end EF4 intensity as it struck the community of Lone Grove. 35–40 structures at the Bar K mobile home park were obliterated and homes were completely destroyed. Six deaths occurred in the mobile home park; three people were found outside their homes, two inside, and one in a field. The residents did not evacuate the mobile home park despite warnings being issued 35 minutes in advance of the tornado striking. A seventh person died in Lone Grove when their well-built home was destroyed.