User:ChessEric/February 2013 North American storm complex

A large and powerful storm system bought wintery weather and severe weather to much of the country between February 9–12, 2013. Heavy snowfall, sleet, and freezing rain fell across Minnesota, North Dakota, Wisconsin, and Colorado. Severe weather and flooding occurred in southeastern United States with a small, but destructive tornado outbreak struck Texas, Mississippi, and Alabama on February 10. This included a violent multiple-vortex low-end EF4 wedge tornado devastated Hattiesburg, Mississippi.

Impacts
Heavy sleet, freezing rain and snow fell in south central and east central Minnesota while heavy snowfall occurred across central and west central portions of the state with Millerville receiving 14 in of snow.

Tornado outbreak
Further south, the Storm Prediction Center (SPC) had stated as early as February 8 that a few supercells would possibly develop on the 10th and could produce large hail, damaging winds, and a few tornadoes. When the thunderstorm outlook was issued for the 10th, the SPC stated that only a marginal chance for severe thunderstorms existed and that only a few storms would develop. Most of the severe weather activity was expected to develop along the cold front in the form of a squall line. A 10% chance of isolated tornadoes was introduced as the instability remained marginal for the event.

During the morning hours of February 10, a squall line developed along a cold front that stretched from western Arkansas, down through northwest Louisiana, and into east Texas. Simultaneously, a warm front was ascending northward through Mississippi and Louisiana. The area between the fronts became increasingly unstable as the day went on, and four tornado watches were issued across Texas, Louisiana, Mississippi, and Alabama throughout the day as the storms tracked eastward. The watches were issued as very strong wind shear and instability engrossed the area, causing the development of supercell thunderstorms. These watches were issued through the day, with the first being posted at 7 a.m. CST (1300 UTC) and the last one coming out at 5:35 p.m. CST (2335 UTC).

Throughout the afternoon hours, the cold front and the squall line began to stall over portions of Louisiana and Arkansas. The supercells that developed that afternoon ahead of the squall line originated across Louisiana and southern Mississippi. One supercell produced four tornadoes in Mississippi, including an EF2 tornado that tracked through Marion and Lamar Counties and a large wedge EF4 tornado that hit that struck Hattiesburg.

West Hattiesburg–Hattiesburg–Petal, Mississippi
This violent tornado touched down west-southwest of West Hattiesburg at 5:03 p.m. CST (23:03 UTC), causing EF0 damage to tree limbs at the western edge of the community. It rapidly widened and intensified as it moved through residential subdivisions of the city, snapping numerous trees and power lines, severely damaging homes, and expanding to one half-mile wide. Further northeast, it narrowed as it struck Oak Grove High School, causing major damage to the school's athletic complex. Several well-constructed buildings around the school's athletic stadiums were destroyed, with twisting and buckling steel girders noted. Several steel light poles with concrete reinforcement were snapped as well. Vehicles were thrown in considerable distances, one of which was taken from a parking lot of the high school, rolled up a hill and across the baseball field, and then deposited onto the pitcher's mound. Much of the damage in this area ranged from EF2 to EF3 intensity, though an isolated pocket of EF4 damage occurred just to the southwest of the high school, as a well-built brick home was completely flattened with debris scattered downwind. Nearby trees were denuded and debarked. As it then approached I-59, the tornado heavily damaged numerous homes and apartment buildings at EF2 to EF3 strength, and snapped more trees and power lines. It crossed the interstate and entered Forrest County, tearing through densely populated areas of Hattiesburg, resulting in major damage.

In Forrest County, roughly 300 homes and other structures were damaged/destroyed as the tornado moved through various neighborhoods and business districts. The University of Southern Mississippi sustained significant damage to the southern portion of its campus; at least six buildings were damaged and two others were destroyed there. Near the university, a gas station, a strip mall, a church, an apartment building, and multiple homes were damaged/destroyed, and some metal traffic light poles were mangled. The tornado continued through residential areas to the east of U.S. 49, where many trees were uprooted, homes were heavily damaged, and a church's steeple was blown off. Large metal light poles at the athletic fields of Hattiesburg High School were snapped, and the third base wall at the baseball field was destroyed. The gymnasium sustained considerable damage to its roof as well. Near the high school, the American Red Cross Building lost its roof and some of its exterior walls, and the Girl Scouts of Greater Mississippi building had its roof torn off as well. The tornado then impacted the northern fringes of downtown Hattiesburg, damaging or destroying several more homes, snapping numerous power lines, and causing heavy damage to several large brick buildings, three of which were leveled. Damage intensity throughout the city of Hattiesburg ranged from EF2 to EF3. The tornado maintained its strength as it continued into Petal, where an ACE Hardware store was completely leveled and more homes were damaged or destroyed.

Traveling to the northeast of Petal, the tornado began to weaken, causing EF1 to EF2 strength damage to numerous roofs and downing many trees. It weakened to EF1-strength in Perry County before weakening rapidly and lifting in a wooded area just west of Runnelstown at 5:36 p.m. CST (2336 UTC).

The tornado was on the ground for 33 minutes, travelling 22.5 mi with a maximum path width of 0.75 mi. The tornado injured 71 people (8 in Lamar County and 63 in Forrest County) and caused damage amounting to $38.525 million.

Aftermath
President Barack Obama declared Mississippi a federal disaster area following the tornado. Mississippi Governor Phil Bryant issued a State of emergency for Forrest, Lamar, Lawrence, and Marion Counties due to the impact of the severe storms and tornadoes in those counties.

Rain hampered cleanup efforts in the city during the days following the EF4 tornado in Hattiesburg. Schools remained closed in the Hattiesburg area until February 14, 2013, including the University of Southern Mississippi (USM). When schools reopened, school buses had to be borrowed from neighboring school districts as most of Hattiesburg's had been damaged by the tornado. USM had to move classes that were previously held in the eight damaged buildings. USM officials estimated that it would take over 10 million dollars to repair the school. Oak Grove High School in West Hattiesburg lost its athletic facilities as well as a few other buildings. The Lamar County School Superintendent said that it would take months and millions of dollars to repair. Hattiesburg High School also suffered destruction of some of its athletic facilities, including the basketball gym that had undergone renovations just a few weeks before.

Power outages in the area were as many as 13,000 just after the storm, but they were quickly reduced. The American Red Cross and the Salvation Army worked together to provide food and shelter for victims of the tornado and the Mississippi State Department of Health offered free tetanus shots at county health departments for residents of storm-affected counties.

Sempra U.S. Gas & Power donated $100,000 to Hattiesburg area schools and the American Red Cross branch based in Hattiesburg.