February 2009 North American storm complex

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. 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. The Storm Prediction Center announced a "moderate risk" of severe weather for portions of eastern Oklahoma, northeastern Texas, western Arkansas, and northwestern Louisiana. 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==

February 10-11 event 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; 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. The tornado then crossed I-35, killing a truck driver before moving into rural areas and dissipating. The tornado was the strongest tornado in the state during the month of February since modern records began in 1950. The previous record was two F3 tornadoes that touched down on February 17, 1961. An additional 46 people were injured. A total of 114 homes were damaged or destroyed by the tornado and total monetary losses were estimated at $3 million. ==Non-tornadic events==

During the evening of February 10, a long line of severe thunderstorms developed along the tail-end of a cold front in central Texas. Meteorologists predicted embedded supercell thunderstorms that could produce hail up to in diameter and wind gusts up to . North of the squall line, bow echo thunderstorms developed in Missouri, causing widespread wind damage. By the morning of February 11, the squall line reached as far southeast as eastern Louisiana, where winds were recorded in excess of along with hail up to in diameter. Around 12 pm EST (17:00 UTC), the first line of thunderstorms significantly weakened, but a new, narrow line developed in eastern Kentucky and Tennessee. A strong, deep layer wind field prevented a number of tornadoes from forming but instead caused widespread wind damage. Throughout the day, the line of low-topped thunderstorms continued eastward, reaching Ohio and West Virginia by 4 pm EST (21:00 UTC). Several hours later, the line broke apart, with the strongest storms tracking through Pennsylvania. By February 12, rain showers, accompanied by high winds up to , affected most of the Northeastern United States. The large-scale damaging wind event left an estimated $1.7 billion (2009 USD) in losses. West South Central states In addition to the strong tornadoes, Oklahoma was affected by high winds and large hail. The largest hailstones were observed in Okesa at in diameter. Numerous cars were hit and several houses sustained roof damage; the cost of the hail damage was estimated at $100,000. Heavy rains produced by the storms also caused isolated flooding, inundating numerous streets. A lightning bolt struck an oil tank, igniting a fire. The most significant wind damage occurred in Atoka and Coal counties where winds up to destroyed two mobile homes, several barns, and outbuildings. An estimated 15,000 residences were without power following the storms in Texas. Three people were injured in McGregor when their home was destroyed. In Arkansas, high winds produced by the squall line knocked out power to 315,324 residences and caused widespread structural damage. Flooding and high winds in Michigan knocked out power to about 57,000 residences. In southern Michigan, upwards of of rain fell, leading to faster snowmelt. A tight pressure gradient behind the cold front produced strong winds across portions of Indiana and Illinois, with many areas seeing sustained winds of with gusts up to . Heavy rain, warmer temperatures, and snow melt contributed to saturated grounds. the highest measured value was in Hamilton County. In Tippecanoe County, several homes had shingles and siding blown off and fallen trees blocked roads. Winds in southwestern Indiana damaged power lines weakened from the ice storm in late January. Heavy rains produced by the same system inundated several streets in flood-prone towns in Ohio. The most significant damage resulted from the strong pressure gradient behind the frontal system. Thousands of tree were knocked down or uprooted by winds gusting in excess of , cutting power to 585,775 residences. Some windows were damaged or broken by flying debris or fallen trees. Power outages forced numerous schools to close for at least two days following the storm. A large barn was leveled just north of Brighton in Lorain County by winds. Throughout the state, damages from the storm system amounted to $4.7 million. Northeastern states Hurricane-force wind gusts up to caused significant damage and power losses in Pennsylvania. In Pottstown, a large portion of the roof of a four-story building was blown off, forcing residents to evacuate the building. An pillar was knocked down at the First Moravian Church in Easton. In Northampton County, a fire sparked by fallen power lines destroyed a barn and partially melted a nearby metal shed. The blaze was fully contained by 40 firefighters. Another fire sparked by fallen power lines destroyed a garage in Lower Merion Township. In Philadelphia, the roof of a portable classroom began to peel off, forcing the forty students inside to evacuate to a safer structure. A large tree fell through one house and severely damaged the roof of a nearby home. Numerous major highways and local streets were shut down for several hours to allow cleanup crews to clear debris. Throughout the state, damages from the storm system amounted to $3.7 million. Unseasonably warm temperatures and heavy rains from the storm system increased the snowmelt rate in northern areas of the state. In Genesee County, an estimated of the snowpack melted, triggering flash floods along several rivers. The Tonawanda Creek reached a height of , above flood stage. Several homes were inundated by flood waters throughout the region. In all, 84,624 residences lost power in New York State. The construction worker was killed after a cinder block wall collapsed due to high-winds. Winds in the city gusted to in the Bronx. Throughout Long Island, an estimated 4,000 people lost power. In New Jersey, strong winds gusted up to , bringing down tree limbs that killed two people. A total of 93,816 residences were also left without power at the height of the storm. A total of 8,486 Connecticut residences were left without power after high winds damaged numerous power lines and tree limbs. In Massachusetts, gusts up to brought down several trees and cut power to residences in Middleborough, Boston, Brookline and Hingham. The Western Massachusetts Electric Company reported that at least 360 residences lost power during the storm. Westerly winds and enhanced moisture from lakes led to of snow falling in parts of The Berkshires. A downed power line sparked a fire that burned a few miles southwest of Leighton. At least 8,300 customers lost power in various parts of the state. In Huntsville, a car carrying four people lost control on rain-slicked roads and crashed into a van, killing one of the occupants and injuring the other three. Effects in Georgia were largely limited to scattered instances of downed trees and power lines across northern and central parts of the state. Peak gusts were estimated at . Widespread damage to trees occurred across most of Tennessee as the storm moved through, with Central Tennessee and East Tennessee being more severely affected. Many areas estimated or measured winds in excess of , with peak gusts estimated at near Collinwood and Lawrenceburg. Mostly minor damage to homes was reported in multiple counties; some had their roof significantly damaged. Widespread power outages occurred, One person was killed by high winds in Davy, West Virginia when a gymnasium roof collapsed. Throughout the state, power was knocked out to an estimated 225,000 residences. In Montgomery County, Virginia, winds knocked down power lines which sparked two brush fires, one of which burned a total of . Winds up to cut power to 28,059 residences in the state. The strong winds also cut power to 50,820 residences in Maryland. ==Aftermath==

In the wake of the tornado outbreak, law enforcement officers, including 30 National Guard troops, were sent to Lone Grove to assist with rescue efforts. The American Red Cross opened shelters in Ardmore, Edmond, and Oklahoma City. About 100 volunteers from the Sorghum Mill Estates Neighborhood Association traveled to affected areas in Edmond to help with cleanup efforts. A local restaurant provided free meals to the volunteers as they assisted relief workers. They also sent three food trucks, containing a total of 619 meals, 900 drinks, and about 500 snacks, to Ardmore. On February 22, the New Life Baptist Church sent drinks and prepackaged snacks, along with items needed for clean-up. Baptist Disaster Relief assisted in Lone Grove with food and emotional care. The Oklahoma City Thunder of the National Basketball Association (NBA) gave away two tickets to anyone who made a donation of $25 or an equivalent amount of food to benefit victims of the tornado. A concert featuring Chris Cagle and other local musicians at Heritage Hall in Ardmore raised over $18,000 to benefit Carter County tornado victims. Another concert set up by the Salvation Army raised $2,300 more for victims. On February 15, President Obama approved Henry's request for federal assistance in Carter, Logan and Oklahoma counties. A disaster recovery center was set up by the Federal Emergency Management Agency (FEMA) on February 20. Homeowners were allowed to borrow $200,000 to repair damages to their home or find a temporary or permanent shelter. They were also allowed to borrow up to $40,000 to replace lost property. Businesses were allowed to borrow up to $2 million for damage repair, property loss, and economic loss. By February 23, about $781,000 had been given in federal grants. On February 25, FEMA approved Governor Henry's request for public assistance in Carter, Coal and Love counties. The estimated cost to clear the 7,000 tons of debris in Lone Grove was placed at $500,000, of which $90,000 has been paid for by FEMA. The Department of Homeland Security offered to assist with the reconstruction of homes and businesses and to support those who were left homeless. ==See also==