April 25–28, 2011 tornado outbreak

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April 25–28, 2011 tornado outbreak
Storm system on April 27
Date of tornado outbreak: April 25–28, 2011
Duration1: 3 days, 7 hours, 18 minutes
Maximum rated tornado2: EF5 tornado
Tornadoes caused: 358 confirmed
(Record for a continuous outbreak)
Highest winds: 210 miles per hour (340 km/h) (Hackleburg, AL/Phil Campbell, AL EF5)
Largest hail: 4.5 inches (11 cm) in diameter in Saltville, Virginia on April 27
Damages: ~$11 billion (2011 USD)[1]
Fatalities: 324 (+24 non-tornadic)[2][3][4][5]
Areas affected: Midwest U.S., Southern U.S., Northeastern U.S. and Southern Ontario, Canada

1Time from first tornado to last tornado
2Most severe tornado damage; see Enhanced Fujita Scale

The April 25–28, 2011 tornado outbreak was the largest and one of the deadliest tornado outbreaks ever recorded, affecting the Southern, Midwestern, and Northeastern United States and leaving catastrophic destruction in its wake.[6][7] While the states that were hardest hit were Alabama and Mississippi, the outbreak also produced destructive tornadoes in Arkansas, Georgia, Tennessee and Virginia, and affected many other areas throughout the Southern and Eastern United States. In total, 358 tornadoes were confirmed by the National Weather Service (NWS) and Environment Canada in 21 states from Texas to New York to southern Canada. Widespread and destructive tornadoes occurred on each day of the outbreak, with April 27 being the most active day with a record of 211 tornadoes touching down that day from midnight to midnight CDT (0500 – 0500 UTC). Four of the tornadoes were destructive enough to be rated EF5, which is the highest ranking possible on the Enhanced Fujita scale; typically these tornadoes are only recorded about once each year or less.[6]

In total, 348 people were killed as a result of the outbreak, which includes 324 tornado-related deaths across six states. In addition, 24 fatalities were not caused by tornadoes, but were confirmed to be as a result of other thunderstorm-related events such as straight-line winds, hail, flash flooding or lightning.[8][9] In Alabama alone, 238 tornado-related deaths were confirmed by the Storm Prediction Center (SPC) and the state's Emergency Management Agency.[2][8]

April 27 had the most tornado-related fatalities in the United States in a single day since the "Tri-State" outbreak on March 18, 1925, when at least 747 people were killed.[10][11][12][13] Nearly 500 preliminary local storm reports were received for tornadoes over four days, including 292 in 16 states on April 27 alone.[14] This event was the costliest tornado outbreak and one of the costliest natural disasters in United States history (even after adjustments for inflation), with total damages of approximately $11 billion (2011 USD).[1]

Meteorological synopsis[edit]

This animation of satellite images from April 26 through the morning of April 28 shows the development of the weather system which spawned the tornadoes.

The outbreak was caused by a vigorous upper-level trough that moved into the Southern Plains states on April 25. An extratropical cyclone developed ahead of this upper-level trough between northeastern Oklahoma and western Missouri, which moved northeast.[15] Conditions were similar on April 26, with a predicted likelihood of severe thunderstorms, including an extended threat of strong to violent long-track tornadoes during the afternoon and evening hours; mixed-layer CAPE values were forecast to be around 3000–4000 J/kg, around east Texas, Louisiana and Arkansas. The storm mode on April 26 was predicted to consist of mostly discrete supercells during the afternoon and early evening, shifting over to a mesoscale convective complex, with more of a threat of damaging winds and hail during the nighttime hours.[16]

As the storm system moved eastward toward the Ohio, Mississippi and Tennessee Valleys on April 27, a very powerful 80–100 knot mid-level jet stream moved into the Ohio and Tennessee Valleys, behind the trough, creating strong wind shear, with a low pressure center moving quickly northeastward across those areas on the 27th. On the afternoon of April 27, CAPE values were estimated to be in the range of 2000–3000 J/kg across Louisiana and southern Mississippi, with the moderate instability moving northeastward across the southern Tennessee Valley; in addition, temperatures across the southeastern United States ranged from the 70s °F (mid-20s °C) to the lower 90s °F (near 35 °C). Helicity levels ranged from 450–600 m2/s2, which were supportive for significant tornadic activity and strong to violent long-track tornadoes.[17]

In total, 56 severe weather watches (2011 watches, 199–256; two watches were omitted in error) were issued by the Storm Prediction Center (SPC) over those four days in the outbreak area, including 41 tornado watches (10 of which were PDS watches) and 15 severe thunderstorm watches.[18][19]

April 25[edit]

A large area of possible severe storms for April 25–27 was forecast as the Storm Prediction Center (SPC) issued a moderate risk of severe weather for three consecutive days, centered over Arkansas through Tennessee. By the late-afternoon hours of April 25, several tornadoes had been reported across a few states, including two which caused significant damage in Oklahoma and Texas. At 3:25 p.m. CDT (2025 UTC), the SPC issued a Particularly dangerous situation (PDS) tornado watch for much of Arkansas and parts of Missouri, Oklahoma, Texas and Louisiana.[20] Tornadoes were scattered that day until early evening, when an intense tornadic cell (a supercell that has produced or is capable of producing a tornado) tracked near the Little Rock metropolitan area and a tornado emergency was declared for Vilonia, Arkansas. A large EF2 wedge tornado struck the town, causing severe damage and killing four people.[21][22] A strong EF3 tornado also struck Hot Springs Village that evening, causing severe damage and one death. Another tornado caused extensive damage to Little Rock Air Force Base.[23] Severe flooding continued across a large area from the Red River valley to the Great Lakes.[24]

April 26[edit]

A high risk of severe weather was issued for April 26 for portions of Louisiana, Arkansas, Oklahoma and Texas along and near the Interstate 30 corridor as conditions became even more favorable for extreme weather.[25] A large PDS tornado watch with very high tornado probabilities was issued that afternoon for that same area.[26] Widespread tornado warnings were issued in that area later that evening.[27][28][29]

Tornado watches were also issued for the Lower Great Lakes in the afternoon hours, and supercells began to track across southern Michigan in the early evening. Two tornadoes touched down in Michigan and caused damage to farm structures. Further east, severe thunderstorms caused scattered wind damage and large hail across Pennsylvania and New York. Two-inch-diameter hail was reported in Lock Haven, Pennsylvania.[30] An isolated supercell moved across Central New York throughout much of the afternoon, producing golf ball-sized hail in Syracuse, and spawned a very brief EF1 tornado in Verona Mills, causing primarily tree damage. Another tornado in Gilbertsville caused significant damage to an athletic field at a school.[31]

Numerous tornadoes touched down across Texas, Louisiana, Arkansas, and several other states. Most of the tornadoes were weak, but a few caused considerable damage. A long-track wedge tornado caused EF2 damage across Texas and Louisiana.[32] An EF3 tornado destroyed multiple structures and caused severe damage at Fort Campbell, Kentucky.[33]

April 27[edit]

Significant ground scouring near Philadelphia, Mississippi caused by a fast-moving EF5 tornado that killed three people.

For the second day in a row, the SPC issued a high risk of severe weather for the Southern United States, and late that morning the SPC increased the probability for tornadoes to 45 percent along a corridor from Meridian, Mississippi to Huntsville, Alabama, an extremely rare issuance exceeding the high risk standards. Conditions for tornadoes became increasingly favorable for an extreme tornado outbreak.[34] Early in the morning, a squall line of severe thunderstorms packing straight-line winds and numerous embedded tornadoes affected North and Central Alabama and parts of Middle and East Tennessee. These storms knocked out power and telephone lines in a few areas; these outages would become much more widespread as the day continued. This preliminary line of storms also caused some NOAA weather radio transmitter sites to stop functioning for the remainder of the outbreak. As a result, many people had no warning of approaching tornadoes later in the day.[35]

During the afternoon, a tornado emergency was declared for Neshoba County, Mississippi as a large tornado was reported on the ground by storm spotters and a camera atop a television tower from ABC affiliate WTOK-TV (channel 11) in Meridian, Mississippi. This powerful EF5 tornado caused incredible damage near Philadelphia, Mississippi where homes were swept away, vehicles were thrown, and the ground was scoured out to a depth of 2 feet (0.61 m) by the tornado. Three people died in this tornado when a mobile home was picked up, thrown into a wooded area, and destroyed.[36] The atmosphere became increasingly unstable throughout the late afternoon, causing more explosive supercell development. A widespread complex of supercell storms overspread the states of Mississippi and Alabama and violent tornadoes began rapidly touching down as the evening progressed. Four tornadoes were officially rated as EF5 on the Enhanced Fujita scale that day. These tornadoes affected several counties in the states of Mississippi and Alabama, especially the towns of Smithville, Mississippi; Hackleburg and Phil Campbell, Alabama; Philadelphia, Mississippi; and Rainsville, Alabama. This marks only the second day in history (the other being the April 3, 1974 Super Outbreak) that there were more than two F5/EF5 tornadoes.[37]

A dangerous and destructive tornado struck the city of Cullman, Alabama at around 3:00 p.m. CDT (2000 UTC). This large, multiple-vortex tornado was captured on several tower cameras from television stations such as Fox affiliate WBRC (channel 6) and ABC affiliate WBMA-LD/WCFT-TV/WJSU-TV (channels 58, 33, and 40) out of Birmingham. The tornado caused extensive destruction in downtown Cullman, a city of about 20,000 people; the tornado was ultimately rated an EF4. The final damage count was 867 residences and 94 businesses in Cullman.[38] At around 4:00 p.m. CDT (2100 UTC), a tornado struck Lawrence County, Alabama, causing severe damage and killing a couple dozen people. At around 5:10 p.m. CDT (2210 UTC), a very large and exceptionally destructive tornado struck Tuscaloosa, Alabama, and about 40 minutes later, the same tornado struck the northern suburbs of nearby Birmingham.[39] A tornado emergency was issued for both cities, along with many other cities that day. Many local television stations, including WBRC and WBMA-LD/WCFT/WJSU, as well as CBS affiliate WIAT (channel 42), captured footage of this long-track tornado in both Tuscaloosa and Birmingham. A debris ball was observed by the Birmingham NEXRAD, indicating that the tornado was causing extreme damage.[40] Photos from the damage path showed total devastation. The path of this tornado struck several of the same small communities as the April 1956 F4, the April 1977 F5 and the April 1998 F5 tornadoes that hit portions of the Birmingham area. The supercell responsible for the Tuscaloosa/Birmingham EF4 tornado originated in Newton County, Mississippi at 2:54 p.m. CDT (1954 UTC) and tracked 380 miles (610 km) to Macon County, North Carolina where it dissipated at 10:18 p.m. CDT (0318 UTC). The supercell also produced the Ohatchee/Piedmont, Alabama EF4 tornado as well as an EF3 northeast of Cartersville, Georgia.[41] Several small Alabama towns including Hackleburg, Phil Campbell, Rainsville, Harvest, Hueytown, Pleasant Grove, Tanner, and Concord also suffered catastrophic damage.[42][43]

A secondary area of severe weather also developed that afternoon and evening along the Interstate 81 corridor from central and northern Virginia northward through Maryland, Pennsylvania, and New York, continuing into early April 28. Many tornadoes touched down in this area as well.[44][45] Although most were weak, a few scattered strong tornadoes were noted in New York and Pennsylvania.[46] One EF2 tornado touched down in near the town of Halifax, Virginia, and caused severe damage to homes in the area, resulting in one death.[47] Tornado alerts were issued for Southern Ontario as far north as Ottawa as well; one tornado was later confirmed in Fergus, Ontario.[48]

Map of all tornado (red), severe thunderstorm (yellow), and flood (green) warnings issued on April 27.

Powerful tornadoes touched down across Tennessee as well that evening. A violent EF4 struck the town of New Harmony, Tennessee, where homes were leveled, vehicles were tossed, and four people were killed.[49] Two EF3 tornadoes crossed paths in Greene and Washington counties (coming a couple hours apart), resulting in eight fatalities. The rural communities of Horse Creek and Camp Creek suffered major damage.[50][51] A very large EF4 wedge tornado leveled a mile-wide swath of forest though 14 miles (23 km) of Great Smoky Mountains National Park.[52] At Chilhowee Lake, large metal power line truss towers were torn and thrown from their concrete supports that they were anchored to.[53]

A statewide review by emergency management officials recorded 249 fatalities in Alabama.[8] Damage and power outages in the Huntsville area were so widespread that at one point over 650,000 people were out of power in the Tennessee Valley Authority system. The tornado that came through Limestone County severely damaged main power lines coming from Browns Ferry Nuclear Plant. These towers were the main supply of electrical power to much of North Alabama and some were without power for two weeks. The tornado just missed the Limestone Correctional Facility, which less than a year later would be struck by another tornado. Severe tornado damage, including 20 deaths, also occurred in Ringgold, Georgia; Apison, Tennessee; and Cleveland, Tennessee due to a violent and long-track EF4 tornado. Another violent and deadly tornado struck the town of Ohatchee, Alabama, where a destructive EF4 destroyed many homes and killed 22 people. Other notable destructive and deadly tornadoes occurred that day in and around the towns of New Wren, Mississippi; Enterprise, Mississippi; Cordova, Alabama; Trenton, Georgia; Lake Martin, Alabama; and Eoline, Alabama.[54]

The Storm Prediction Center received 292 reports of tornadoes in the preceding 24 hours.[14] It broke the record for the most tornado touchdowns in 24 hours with 211 in the United States from midnight to midnight CDT (0500 – 0500 UTC) breaking the 24-hour record of 147 (in both totals, excluding confirmed tornadoes outside the United States that were part of the outbreak) set by the Super Outbreak. Of those 211 tornadoes, 59 were in Alabama and 71 were in Tennessee, accounting for well over half of the tornadoes that touched down on April 27.[55] On April 27 alone, the National Weather Service in Huntsville, Alabama issued 92 tornado warnings, 31 severe thunderstorm warnings, and seven flash flood warnings.[56]

April 28[edit]

Tornado watches were issued for the Atlantic coast from Pennsylvania to Florida at the start of the day and continued through the morning and early afternoon, but tornadoes were forecasted to generally be weaker and more isolated.[57] Even so, several people were killed across the region and tornadoes were reported in Pennsylvania,[58] New York, Virginia,[59] North Carolina,[60] South Carolina,[61] Georgia, Florida,[62] and Maryland.[63] Although tornado watches were issued, no tornadoes were spotted in New Jersey[64] or Washington, D.C.[59] In the wake of the tornadoes and severe thunderstorms, widespread flooding hit the Midwest, South, and Eastern Seaboard, with extensive flood and flash flood warnings issued.[65] One particularly damaging and deadly EF3 tornado struck the town of Glade Spring, Virginia very early in the morning, where three people died.[66] Other strong tornadoes caused severe damage and a few fatalities in Georgia during the early morning hours.[67] The last tornadoes of the outbreak touched down that afternoon in eastern North Carolina, which was hard hit in the April 16 outbreak, but they were all weak this time.[68] The system moved out into the Atlantic Ocean that evening, with the exception of isolated thunderstorms over central Florida that night into April 29, although there were no tornadoes then.[69]

Notable tornadoes[edit]

Confirmed
Total
Confirmed
EF0
Confirmed
EF1
Confirmed
EF2
Confirmed
EF3
Confirmed
EF4
Confirmed
EF5
358 129* 143 49 22 11 4

* - One tornado touched downed in Ontario, Canada on April 27 and was rated as an F0. It is counted as an EF0 in this table.

edit this table

Outbreak death toll
State/Province Fatalities
Alabama 238
Arkansas 5
Georgia 14
Mississippi 31
Tennessee 32
Virginia 4
Totals 324
Only tornado-related deaths are included
(24 deaths were not caused by tornadoes)

Vilonia, Arkansas[edit]

The first tornado of the outbreak to cause multiple deaths was a large EF2 that struck the small town of Vilonia, Arkansas in Faulkner County around 7:30 p.m. CDT (0030 UTC) on April 25.[70] A tornado warning was issued for the town roughly 30 minutes prior to the tornado's arrival and the relatively low loss of life is attributed to this lead time.[71] A tornado emergency was declared at 7:24 p.m. CDT (0024 UTC) for Vilonia shortly before the tornado struck.[72] Four people were killed in the town and many more injured. Numerous structures were also damaged or destroyed. One mobile home was completely destroyed and debris from the home was scattered a significant distance from where it stood. Many other homes were badly damaged by the tornado. Numerous trees were snapped and uprooted and a church was destroyed. Within five minutes of the storm, local firefighters arrived in the town and began search and rescue efforts.[70][71] Following the tornado, 85 members of the National Guard were deployed to assist in search and rescue, debris clearing, security and traffic control.[73]

Philadelphia, Mississippi[edit]

Pavement scoured from a road near Philadelphia.

The first EF5 tornado in the outbreak touched down near the city of Philadelphia, Mississippi. The tornado touched down at 2:30 p.m. CDT (1930 UTC) and traveled a path of 29 miles (47 km) through Neshoba, Kemper, Winston, and Noxubee counties, resulting in three fatalities and significant high-end destruction. This same supercell would later produce the Cordova, Alabama EF4, the Rainsville, Alabama EF5, and the Ringgold, Georgia EF4 tornadoes.[74]

Much of the damage in the core of the tornado in this area was rated as high-end EF3 to EF5. The three fatalities occurred in northwest Kemper County when a strapped down doublewide mobile home was thrown a distance of approximately 300 yards (270 m) into a treeline, and then obliterated with the debris and framing scattered many hundreds of yards down the path. There was no indication of ground impacts between the original site of the mobile home and where it ended up to indicate that the mobile home bounced extensively as it travelled. Two traditional frame brick homes in southeast Winston County were completely leveled and swept away. New vehicles were thrown or rolled hundreds of yards before being wrapped around trees and left almost beyond recognition. In parts of northeast Neshoba and northwest Kemper counties, there was very high-end tree damage with extreme denuding and debarking of trees, which were torn from the ground and thrown. Nearby, a large area of ground was scoured out to a depth of two feet in places, and asphalt was scoured off of roads.[75]

This was the first tornado to cause F5/EF5 damage in Mississippi since the Candlestick Park tornado of March 3, 1966. Additionally, this marks the first time since statistics have been kept that two EF5 tornadoes have been recorded on the same day in Mississippi, with the tornado in Smithville, Mississippi also rated as an EF5. Prior to this, the last confirmed EF5 tornado was the Parkersburg, Iowa tornado on May 25, 2008.[75]

Cullman/Arab, Alabama[edit]

Damage to the First Methodist church in downtown Cullman, Alabama.

Rated an EF4, this tornado tracked straight through downtown Cullman.[76] The tornado touched down at 2:40 p.m. CDT (1940 UTC) on April 27 and tracked a 47-mile (76 km) damage path through Cullman, Morgan and Marshall counties, resulting in six fatalities.[77]

The Cullman tornado first touched down on the north side of Lewis Smith Lake and caused structural damage near Crane Hill, before tracking towards Cullman. The tornado was first seen and then tracked on tower cameras, including one operated by WBMA-LD/WCFT/WJSU, for several minutes. That camera captured the destruction of a tower belonging to Cullman area low-power television station WCQT-LP as the tornado passed through the city. Radio stations in downtown Cullman also reported on the tornado and some even captured the tornado passing over until power was knocked out. The courthouse and nearby emergency management building took a direct hit from the tornado. Many well-known businesses such as Vincent's Furniture, The Cullman Times, and the Busy Bee Cafe were either severely damaged or destroyed as well.[76]

Downtown Cullman was badly damaged by the tornado, with the major damage being along a two-block area through the center of the downtown business district. The tornado more or less followed U.S. Highway 278 through the city, which in turn led to the tornado crossing and creating extensive damage along many major intersections, including those with Interstate 65, U.S. Highway 31, Alabama Highway 157, and Alabama Highway 69. There were several homes destroyed from the tornado with much damage resulting from fallen trees. Residential damage was especially heavy along West Main Avenue and in the eastern downtown Historic District. Many homes destroyed exceeded 100 years in age. East Elementary School, one of the city's two elementary schools, which was located in the middle of the Historical District, received moderate damage. Minor to moderate wind damage occurred on the campuses of Cullman Middle School and Cullman High School as well.[77]

The tornado continued northeast and grew into a large wedge. It then passed just north of Fairview, destroying several homes in the area. The tornado crossed into Marshall County and leveled a gas station on the northern edge of Arab, Alabama along with completely crippling Arab's power grid and obstructing many roads with trees. Trees in the area were snapped and ripped from the ground, some of which were never found. Homes in the area were found swept away from their foundations. The tornado damaged and destroyed several other homes north of Union Grove before finally dissipating.[77]

Hackleburg–Phil Campbell–Tanner, Alabama/Huntland, Tennessee[edit]

EF5 damage in Phil Campbell.

A tornado touched down in Marion County, Alabama about 5 miles (8.0 km) west-southwest of Hamilton around 3:00 p.m. CDT (2100 UTC) on April 27, leaving massive damage along its track. The storm would eventually reach the Hackleburg area, completely leveling many homes and businesses, including a large plant operated by Wrangler. Most of the structures in downtown Hackleburg were badly damaged and Hackleburg High School was destroyed. Well-built homes were wiped cleanly from their foundations and cars were thrown hundreds of feet. According to the Red Cross, 75 percent of the town was destroyed.[78] While initially rated as an EF3, the rating was increased to EF5 after further analysis of the damage, making it the first F5/EF5 tornado in Alabama since the Birmingham tornado of April 8, 1998.[79]

The town of Phil Campbell experienced significant devastation of the same magnitude as Hackleburg. Numerous well-constructed houses were swept away as the tornado tore through town. At least three churches along the path sustained significant damage, with one church in the town being completely destroyed and having only the foundation slab remaining. Multiple mobile homes throughout the path were completely destroyed, and their mangled frames were tossed at least 25 to 50 yards (23 to 46 m). Cars were tossed and destroyed throughout the path of the tornado, with one car wrapped around a debarked tree. A 25-foot (7.6 m) section of pavement was torn from a road in this area as well. EF5 damage continued northeast of the town, where several high voltage TVA power line trusses were twisted and toppled. The tornado continued into Lawrence County, near the Mount Hope area, where significant devastation was incurred to single-family homes and a restaurant. Nothing but the foundation and a pile of debris remained in this area, and a small portion of the restaurant foundation buckled.[80]

The tornado moved northeast, causing significant devastation in and around the Langtown community north of Moulton. It then continued through the northwest corner of Morgan County, crossed Wheeler Lake, and moved into Limestone County, coming within 2 miles (3.2 km) of Browns Ferry Nuclear Power Plant. The tornado caused power outages in the area, and the plant had to be shut down. The tornado continued towards the small community of Tanner.[81][82][83] Tanner experienced a large swath of EF4 damage and a narrow corridor of "high-end EF4 to near-EF5 damage". The storm "completely wiped clean" several well constructed homes with anchor bolting.[81] As the storm crossed U.S. Highway 72 in eastern Limestone County, the tornado destroyed a Doppler radar operated by NBC affiliate WAFF (channel 48) and continued into East Limestone, a heavily populated area of Limestone County where numerous homes were damaged or destroyed. As the storm crossed into Madison County, it approached the densely populated suburban communities of Harvest and Toney, where it either damaged or destroyed hundreds of homes, especially in the Anderson Hills and Carter's Gin subdivisions. Many homes were reduced to rubble, and the damage in this area was rated EF4. The tornado completely destroyed a Piggly Wiggly grocery store in Harvest and severely damaged a convenience store and local bank, which was shut down for months following the event.[84] The storm progressed across Pulaski Pike in northwest Madison County, damaging many homes. In all, hundreds of homes received moderate to major damage along the path from Limestone to Madison County with many of these being total losses.[81]

The tornado then moved into Tennessee and continued south of Huntland. Isolated and minor EF0 to EF1 damage was noted through most of its path in Tennessee. The worst damage, however, was to a cinder block utility building and was rated lower-end EF3. Most of its roof was removed, with over half of its downwind wall pushed outward.[83]

In total, this tornado killed 72 people, all in Alabama.[2] This made it the deadliest single tornado ever to strike the state of Alabama as well as (at the time) the deadliest in the United States since the 1955 Udall, Kansas tornado that killed 80 people.[85][86] In addition to being the deadliest, this tornado also had the longest track of any tornado in the outbreak, with its path extending 132.1 miles (212.6 km) across Northern Alabama and into Tennessee.[83]

Smithville, Mississippi[edit]

Extreme damage at a residence in Smithville. Note the concrete foundation slab partially pulled out of the ground.

A violent tornado struck Smithville, Mississippi at 3:44 p.m. CDT (2044 UTC) on April 27, causing extreme damage. An NWS damage survey reported EF5 damage, with numerous homes, a post office, a police station, and what was listed as the "water system" completely destroyed, with 52 homes and 7 businesses damaged to varying degrees. Multiple newly constructed two-story brick homes were swept cleanly from their foundations and trees were debarked.[87]

Final assessments determined that 150 homes, 14 businesses, and 4 churches were destroyed by the tornado in Smithville. The homes were well-built, bolted to their foundations, and of recent construction, but the storm was violent enough that many were reduced to bare foundations and all appliances and plumbing fixtures in the damage path were "shredded or missing". A pickup truck that was thrown from one residence was never found. Shrubbery around the perimeter of some of the homes was shredded as the tornado moved through.[87] A large area of gravel and asphalt was sucked off of a street, and a semi-truck was tossed about 0.5 miles (0.80 km) as well.[88]

Vegetation in the path of the tornado was stripped away, and the ground was deeply scoured west of town. At one residence along Highway 25, the house was completely swept away, and the concrete foundation slab was pulled up out of the ground and displaced slightly, with a large section of the slab completely missing near the center. A large funeral home was completely swept away on the east side of town, leaving nothing but a bare concrete slab at the site, and an SUV was thrown 0.5 miles (0.80 km) into the Smithville water tower; the vehicle then bounced off and was hurled an additional 0.25 miles (400 m), being found crushed and compacted into a small ball.[87] The NWS determined that this tornado continued across the Alabama state line and struck Shottsville, Alabama at EF3 intensity, where homes were destroyed and seven people were killed. It continued to the northwest of Hackleburg where it caused mostly tree damage before lifting. The damage path was 37.2 miles (59.9 km) long and 0.5 miles (0.80 km) wide, and it killed 23 people along its path.[2][89]

Cordova/Blountsville, Alabama[edit]

This long-tracked EF4 tornado touched down in Pickens County, northeast of Pickensville at 3:40 p.m. CDT (2040 UTC), and destroyed a few chicken houses and tossed grain feed bins up to 100 yards (91 m) northeast of Reform. The tornado caused roof damage to houses and destroyed a few outbuildings before moving into Tuscaloosa County and briefly into Fayette County, causing tree damage and minor structural damage. The tornado then moved back into Tuscaloosa County, causing mostly minor tree and structural damage before crossing into Fayette County once again. It completely destroyed at least one mobile home, with the frame being separated and the remaining debris being thrown a considerable distance. The tornado appeared to strengthen even further and several mobile homes were completely destroyed with debris thrown a considerable distance and frames twisted and thrown. Many trees were downed as well before the tornado moved into Walker County. It weakened and caused mostly minor damage to trees and mobile homes. South of Oakman, numerous trees were snapped and uprooted, a cell phone tower was knocked down, and mobile homes were destroyed. It then rolled vehicles and completely destroyed a cinder block house to the southeast of Oakman. The tornado weakened considerably as it approached Corridor X of the Appalachian Development Highway System, with only minor tree damage, before it strengthened significantly as it entered the Cordova area as a 0.5-mile (0.80 km) wide EF3.[90]

Overhead view of Cordova damage from the west (looking east).

In Cordova, numerous homes and manufactured houses were either damaged or destroyed in this area along with many trees being downed. Some homes were swept off of their foundations. Buildings in downtown Cordova had already been damaged by an EF3 tornado earlier that morning and received further damage from this tornado. East of Cordova, the tornado crossed into Blount County and across the Mulberry Fork of the Black Warrior River. It intensified into a violent EF4 in this area, as it destroyed two single-wide mobile homes and a single family home. One of the mobile home undercarriages was missing, having been tossed at least 500 yards (460 m). A small bulldozer was flipped over, a pickup truck was tossed 200 yards (180 m), and a dump truck was tossed 50 yards (46 m) and destroyed. A two-ton trailer was thrown 1 mile (1.6 km) and two double-wide mobile homes were tossed at least 100 yards (91 m). A mobile home was tossed 100 yards (91 m) up a 50 foot (15 m) embankment and destroyed. South of Sipsey, numerous homes and manufactured homes were either damaged or destroyed along this path.[90]

The tornado crossed into Cullman County twice, but it quickly moved out both times. South of Arkadelphia, a second area of EF4 damage was observed, as a block foundation home was swept away and a car was thrown 130 yards (120 m). In Blountsville, the tornado damaged multiple well-built brick and slab foundation homes, one of which had the exterior walls collapse. The storm continued to the northeast and out of Blountsville, where two additional homes sustained high-end EF3 damage. A large portion of one of the homes was wiped off of its foundation.[90] The tornado then moved into Marshall County, causing significant damage to a house and downing numerous trees. A shed suffered roof damage and an industrial plant was completely destroyed. The tornado then moved into a wooded area, weakened, and eventually lifted south-southwest of Guntersville at 5:56 p.m. CDT (2256 UTC).[91]

This tornado was on the ground for two hours and sixteen minutes, tracking for 127.8 miles (205.7 km) across seven counties. It was rated as a low-end EF4 with winds of 170 mph (270 km/h). In total, 13 people were killed and 54 others were injured.[90][91]

Tuscaloosa/Birmingham, Alabama[edit]

Satellite image of the tornado's track through Tuscaloosa.

A large wedge tornado touched down in rural Greene County, Alabama and tracked across neighboring Tuscaloosa County, including the southern and eastern portions of Tuscaloosa at around 5:10 p.m. CDT (2210 UTC) on April 27.[39][92] Debris from the tornado was reported to be falling from the sky across Birmingham over 20 miles (32 km) away in Jefferson County. Skycams operated by Tuscaloosa television station WVUA-CA (channel 7) as well as Birmingham Fox affiliate WBRC (channel 6), ABC affiliate WBMA-LD/WCFT-TV/WJSU-TV (channels 58, 33, and 40), and CBS affiliate WIAT (channel 42) captured video of the tornado as it struck Tuscaloosa (WIAT took home multiple awards including a regional Edward R. Murrow Award for "outstanding live coverage" of the event).[93] Several stores and restaurants in a business district at the intersection of McFarland Boulevard and 15th Street, near the DCH Regional Medical Center, were reduced to rubble by the tornado. Buildings were also reported destroyed on 35th Street, between Interstate 359 and Martin Luther King Jr. Boulevard. As the tornado traveled east to 35th Street and Kauloosa Avenue, the Tuscaloosa Environmental Services and Cintas facilities suffered severe damage. Numerous homes in the Rosedale and Forest Lake neighborhoods, as well as a P&P Grocery store in Rosedale, were devastated. Numerous fatalities occurred in this area. The tornado exited Tuscaloosa and moved through dense forest towards Birmingham, downing thousands of trees. The tornado then struck the community of Concord, flattening the community.[94] The University of Alabama suspended its operations, cancelled its softball and rowing competitions, cancelled its final exams period, and postponed its commencement until August 6.[95]

The flattened Chastain Manor apartment complex in Tuscaloosa.

Many stations, including WIAT, WBMA/WCFT/WJSU, WTVY (channel 4) in Dothan and WSFA (channel 12) in Montgomery, showed television cameras capturing the event as the tornado moved east-northeast across the western and northern suburbs of Birmingham around 6:00 p.m. CDT (2300 UTC). Several suburbs in the area were severely damaged by the massive tornado as it tore through the west side of Birmingham, resulting in multiple fatalities. The suburbs of Pleasant Grove, McDonald Chapel, Pratt City and northern Hueytown were devastated by the tornado as it moved northeast, flattening entire neighborhoods. Entire large factory warehouses were completely swept away in this area. The tornado then struck the suburb of Fultondale, causing EF2 damage to homes and businesses before dissipating northeast of Birmingham.[92][96] Surveys indicated high end EF4 damage from the tornado in Birmingham's western suburbs.[92]

The National Weather Service determined the path length of this violent tornado to be 80.7 miles (129.9 km) with a maximum damage path width of 1.5 miles (2.4 km). The tornado's most intense damage indicated peak winds of around 190 mph (310 km/h); therefore, it was given a final rating of EF4. Reports from Tuscaloosa indicated 44 people were killed, with over 1,000 injured.[92][97] Overall this tornado killed 64 people and injured more than 1500.[2][92] President Barack Obama and First Lady Michelle Obama visited Tuscaloosa on April 29, taking a ground tour of some of the affected areas. Obama was quoted as saying that he has "never seen devastation like this." He stated further that he had already declared a federal state of emergency in Alabama.[98]

Raleigh, Mississippi/Uniontown, Alabama[edit]

Photo of the tornado as it was in southeast Mississippi.[99]

This extremely long-tracked EF4 wedge tornado touched down near Raleigh, Mississippi in Smith County at 5:42 p.m. CDT (2242 UTC), and continued into the Uniontown, Alabama area before dissipating. The tornado initially downed trees, blew skirting from mobile homes, and tore shingles from roofs. The tornado intensified as it moved northeast across Smith County and produced up to EF2 and EF3 damage. One mobile home was picked up, bounced a couple times, and thrown into a tree line, where it was torn apart and debris was scattered up to a mile away, including the frame. The tornado mowed down a stand of pine trees and destroyed two frame houses, with major damage to the interior walls, and the exterior walls completely destroyed. Many power poles were snapped, a mobile home was annihilated, and a large shop building was completely destroyed as well. It then moved into Jasper County and snapped and debarked many pine trees. The first area of EF4 damage was observed near Louin as a frame home and several mobile homes were completely destroyed, with parts of the mobile homes being thrown long distances, and some of the frame home foundation being swept clean. The tornado caused significant damage to a poultry farm and cattle ranch before it weakened briefly. It then destroyed two mobile homes and caused extensive tree and power line damage. The tornado then produced a relatively narrow path of EF1-strength tree and power line damage for several miles, until reintensifying near Rose Hill.[99]

Southeast of Rose Hill, the tornado removed most of the roof of a frame home and caused heavy damage to the exterior walls, took a large section of roof off another frame home, completely destroyed a large mobile home, and caused extensive tree damage. The tornado then weakened again and entered Clarke County as an EF0 while only downing a few trees. The tornado strengthened again and downed trees and power lines as it crossed Interstate 59. Several other homes and mobile homes were destroyed as the tornado moved along the south side of Enterprise. Another area of EF4 damage was observed east of Enterprise as a new home undergoing completion was leveled, with the debris swept off the foundation. Many more frame homes were heavily damaged nearby. Many mobile homes were destroyed and trees were downed in this area as well. It then weakened slightly and produced heavy damage to more houses and mobile homes near Snell and Energy. It also downed many more trees and power lines before moving into Choctaw County, Alabama southwest of Yantley. The tornado killed seven people and injured 35 others on its 65-mile (105 km) portion of the path that was in Mississippi.[99]

In Choctaw County, the tornado traveled 27.5 miles (44.3 km) as it caused extensive damage to homes, one of which was destroyed, and numerous other structures. Several mobile homes were destroyed and many trees were either snapped or completely uprooted. The tornado then moved into Sumter County.[100] In Sumter County, the tornado caused significant damage before it crossed the Tombigbee River and moved into Marengo County. It continued causing significant tree damage as well as destroying several homes and outbuildings along a 26.7-mile (43.0 km) path in this county. The tornado then entered Perry County, the final portion of the path, where it damaged two outbuildings and a grain silo as well as causing significant tree damage before lifting at 8:35 p.m. CDT (0135 UTC).[101]

This tornado was on the ground for nearly three hours, having traveled 125.1 miles (201.3 km) across seven counties in two states. Seven people were killed and another 38 were injured.[99][100][101]

Fyffe/Rainsville, Alabama[edit]

School bus stripped to its frame in Rainsville.

This tornado, rated EF5, began in the Lakeview community northeast of Geraldine, Alabama at 6:19 p.m. CDT (2319 UTC), during the late afternoon of April 27. The tornado tracked northeastward generally parallel to and just east of Highway 75 through Fyffe, Rainsville, and Sylvania and into Georgia, killing 25 people.[102]

The tornado touched down in the Lakeview community, initially causing structural damage to small buildings and snapping trees. The tornado grew in intensity and the path width increased from around 50 yards (46 m) to 0.5 miles (0.80 km) as it entered the Rainsville and Sylvania communities. Damage included houses that were completely removed from foundations and debris scattered for about 1 mile (1.6 km), trees were debarked, and a few mobile homes were completely destroyed with debris strewn for about a mile downstream. Aerial surveys also revealed ground scouring in the area. EF5 damage was noted as a pickup truck was thrown hundreds of yards and torn into multiple pieces, and an 800-pound (360 kg) steel safe anchored to a foundation was torn away, thrown 600 feet (180 m) and had its door torn from its hinges. One home in this area was swept away, and a stone pillar was ripped from the ground, thrown, and broken into pieces, with part of a concrete foundation being ripped out of the ground in the process. Other homes that were swept away were found with their concrete porches torn away and smashed to pieces. An underground storm shelter was partially sucked out of the ground, pavement was stripped from roads, and sidewalk pavement was pulled up at one location.[102][103] In Sylvania, several other houses were completely removed from foundations, some of which contained anchor bolts and foundation straps. The tornado continued to the south of Ider where significant damage was observed. It crossed into Georgia near Fox Mountain as an EF1 with winds of 110 mph (180 km/h). It tracked 3 miles (4.8 km) into Georgia before lifting outside of Rising Fawn. Damage in Georgia was limited to trees and power lines. This tornado came from the same supercell that produced the EF4 that hit the town of Ringgold, Georgia.[102]

Ohatchee/Piedmont, Alabama[edit]

Shoal Creek EF4 tornado.

After the Tuscaloosa/Birmingham tornado lifted, the same supercell produced another tornado, at 6:28 p.m. CDT (2328 UTC) near Argo, Alabama in eastern Jefferson County. It moved into the rural community of Shoal Creek Valley, located between Ashville and Ragland in St. Clair County, Alabama. The tornado intensity varied from EF1 to EF4 as the storm moved northeast.[104]

The tornado mainly downed trees until beginning a path of destruction began just east of County Road 26 (around the 3000 Shoal Creek Road address block; northeast of Odenville) in Shoal Creek Valley. It followed along County Road 22/Shoal Creek Road for approximately 12.5 miles (20.1 km), with the path and width varying greatly along the road. Some areas had damage that was much worse on one side of the road than the other, while other areas showed equal devastation on both sides of the road. Finally, the tornado destroyed many waterfront homes at the end of the valley, crossed Neely Henry Lake, and continued its destructive path in Ohatchee, Alabama. Damage ranged from downed trees and roof damage to total destruction as the tornado roared through the valley at 50–60 mph (80–97 km/h), packing winds of over 180 mph (290 km/h). The official count of homes destroyed or heavily damaged in Shoal Creek Valley was 256. Most phone lines, power lines and poles were destroyed, and water lines were severed by uprooted trees. Entire homes were leveled, and in some cases completely removed by the storm, leaving only brick steps, a fireplace and chimney, or a slab behind. Barns, vehicles, tractors and heavy farming equipment were shredded and moved up to 0.5 miles (0.80 km). Livestock were thrown and killed, and the initial human death toll of 13 would eventually rise to 15 in the area.[104] The tornado eventually continued across rural areas into Georgia. Many outbuildings and homes were destroyed, and many trees were downed across Polk, Floyd, and Bartow counties before the tornado dissipated. Severe damage was noted near Cave Spring where chicken houses and homes were damaged or destroyed, and several people were injured. The damage in Georgia was rated EF2.[105]

This tornado's final death toll, combining fatalities in both St. Clair and Calhoun counties in Alabama, would eventually come to 22.[2]

Ringgold, Georgia/Southeast Tennessee[edit]

Houses in Ringgold, Georgia were completely destroyed by an EF4 tornado.

A violent tornado struck portions of extreme northern Georgia and southeast Tennessee during the mid-evening hours of April 27. It touched down along Davis Ridge Road in Catoosa County, Georgia, and moved through the town of Ringgold. Between 75 and 100 homes were damaged or destroyed; with the most severe damage occurring on Cherokee Valley Road in Catoosa County, where twelve homes were swept away. A Baymont Inn & Suites, located near Interstate 75 was also partially collapsed by the tornado, along with a McDonald's, a Taco Bell, and several gas stations located on Highway 151 in Ringgold at the Interstate 75 interchange (exit 348), and the Catoosa County Department of Family and Children Services and other businesses on Nashville Street in downtown Ringgold. The Kellerhals Center for Visual Arts Education at Ringgold High School was destroyed (RHS itself had minor damage), and Ringgold Middle School was heavily damaged.[106][107]

The storm then crossed the Tennessee state line at 8:28 p.m. EDT (0028 UTC), and moved through Hamilton and Bradley County, Tennessee as a strong EF4, before weakening in Polk County and lifting in McMinn County. Many homes in Hamilton County and Bradley County were leveled, with numerous other homes suffering varying degrees of damage. The tornado moved through the small community of Apison, devastating much of the town and killing eight people. Homes in the area were swept off of their foundations by the tornado. Severe damage also took place in Cleveland as the tornado moved through several neighborhoods, damaging and destroying multiple homes, which resulted in five fatalities in the area. Subdivisions in the southern part of the city sustained major damage, with numerous houses destroyed and a few that were leveled. A gas station in the area was completely destroyed as well. Several trees were felled in Polk County (as the tornado had weakened to EF1-strength), before the tornado crossed into McMinn County.[108][109] The tornado re-strengthened to an EF2 and destroyed two houses and a mobile home before lifting south of Athens.[110]

The tornado killed 20 people along its 57-mile (92 km) path across Catoosa, Hamilton, Bradley, Polk and McMinn counties, including seven fatalities in Ringgold, ranging in age from 16 to 86 years old, including an entire family of four,[111] and another eight in Apison, Tennessee. At least 30 others were injured, some sustaining serious injuries. The tornado was given a rating of EF4 with winds estimated between 175–190 mph (282–306 km/h). The damage path of the tornado was between 13 and 12 mile (0.54 and 0.80 km) mile wide. This tornado is only the eighth in Georgia to be categorized as an F4/EF4 on the (Enhanced) Fujita scale, since official tornado records have been kept in 1950.[106][108][109]

All roads in and out of Ringgold were closed until the morning of April 29; after roads leading to the affected areas were re-opened, residents and business owners were allowed to return, being allowed entry only by providing identification, and informing police a reason why they were entering into the area, in order to curb looting in the storm-damaged areas.[111]

Non-tornadic effects[edit]

Rainfall totals within the United States for the week ending during the morning of April 29, 2011, which shows the extent of the heavy rain event this cyclone contributed towards.

This storm system prolonged an ongoing heavy rain event, which began across Arkansas and Missouri on April 22.[15] Weekly rainfall totals reached 19.73 inches (501 mm) 6 miles (9.7 km) east-northeast of Springdale, Arkansas, 16.20 inches (411 mm) 4 miles (6.4 km) northwest of Poplar Bluff, Missouri, and 14.96 inches (380 mm) at Westville, Oklahoma.[112] On April 25, 2011, thunderstorms with high winds swept through parts of southern and southeastern Ohio. Straight-line winds estimated at 80 miles per hour (130 km/h) uprooted trees, damaged roofs, and downed power lines through Perry County, Ohio and Athens County, Ohio. Strong thunderstorms and heavy downpours which led to flooding were also reported in multiple areas across Upstate New York with heavy flooding in the Syracuse area. The rain also saturated hundreds of lakes in the Adirondack mountains. Interstate 81 was briefly shut down in the downtown area at traffic hour and the State University of New York Upstate Medical University also closed briefly due to flooding in the lobby.[113]

Farther south, flash flooding late on April 26 resulted in two fatalities in Monroe, Louisiana after an apartment complex was swamped. The flooding there was considered to be worse than the flooding after Hurricane Gustav in 2008.[114] In central and northern Arkansas, up to 10.44 inches (265 mm) of rain was reported during that week. The resulting flash flooding in central Arkansas also resulted in five people losing their lives. Many roads were closed due to the flooding there. The flooding was mitigated somewhat by a significant drought that had existed before the storm.[115]

Severe thunderstorms were reported as far north as Northern Ontario on the evening of April 26. Heavy rains and minor flooding were also reported in Northern Ontario from April 26–28.[116][117][118][119] Windstorms were also reported in Southern Ontario and Southern Quebec which resulted in several injuries and one death, damages and power outages.[120][121][122][123][124]

Other fatalities due to straight-line winds occurred in McComb, Mississippi early on April 26[20] and also in Moody, Alabama, Vestavia Hills, Alabama, and Franklin, Tennessee early on April 27 from the squall line with embedded tornadoes.[14][30]

Aftermath[edit]

Alabama Governor Robert J. Bentley declared a state of emergency in the state of Alabama on April 27, due to storm damage from severe thunderstorms earlier that day as well as forthcoming severe weather later that day. States of emergency were also declared in Arkansas, Kentucky, Mississippi, Missouri, Tennessee, and Oklahoma because of the flooding and tornadoes.[125] Following the tornado outbreak on the evening of April 27, President Barack Obama granted a federal emergency declaration for the state of Alabama, giving federal assistance, including search and rescue assets, to the affected region. There have unfortunately been several fatalities since the outbreaks from accidents sustained by volunteers as a part of the clean-up initiative.[126]

More than 2,000 National Guard troops were deployed to Alabama, assisting local and state first responders in search and rescue efforts.[127] President Obama visited the affected areas of Alabama on April 29.[128] Also on April 29, he approved a federal disaster declaration for seven Mississippi counties: Clarke, Greene, Hinds, Jasper, Kemper, Lafayette, and Monroe.[129] By the morning of April 30, the Alabama Emergency Management Agency had confirmed at least 45 storm fatalities in Tuscaloosa, but this was later corrected downward to 44. The tornado killed 64 people along its entire path.[8]

Electricity outage[edit]

Storms through the area severely damaged Tennessee Valley Authority (TVA)'s power grid for transmitting electricity throughout the region. More than 300 power transmission towers, 120 feet (37 m) to 150 feet (46 m) tall, were destroyed in the storms, some "twisted like bow ties" according to National Weather Service meteorologist Eric Holweg. The towers supported some 90 transmission lines, a mixture of 500kV and 161kV lines. Those lines provided power from TVA to 128 regional distributors.[130][131]

Transmission tower bent near Huntsville, Alabama.

TVA lost the ability to transmit power from both Browns Ferry Nuclear Power Plant and Widows Creek Fossil Plant after the storms on April 27, requiring both to be shut down. The nuclear plant's cold shutdown was supported by diesel generators for four days until a second 161kV line could be restored to the plant. The loss of redundant off-site power required a "notification of unusual event", the lowest of four levels of concern dictated by the NRC. Some 60 percent of the sirens for warning residents of worse problems around Browns Ferry were disabled by the storms, and the plant had to arrange plans to use cars with loudspeakers to warn residents in case of another problem. Chief Operating Officer Bill McCollum of TVA stated that it could be weeks before the nuclear plant is up and running again.[82][131] The Nuclear Regulatory Commission stated at a press conference: "The plants' conditions are stable and are being placed in a cooled-down condition."[132][133]

Huntsville was the largest city with no electricity from TVA.[131] All the traffic lights were off, a dusk-to-dawn curfew was imposed, students were sent home from United States Space Camp, and the Panoply Arts Festival was canceled.[134][135][136] Power was restored gradually to Huntsville, beginning with 3 percent on the morning of May 1.[137] Only localized outages remained eight days after the storm.[138] In addition to traffic and safety issues, the outage caused difficulties with water treatment and distribution and retail of all kinds, including gasoline and food purchases.[137][139]

Ontario electricity outages were minor, mostly caused by the windstorms of April 28. Although they affected thousands of people at different times throughout the day, all power was restored by the end of the day.[120][121][122][123][124]

See also[edit]

References[edit]

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Further reading[edit]

External links[edit]

Emergency Tornado Aid

Memorials

Pictures from Tuscaloosa, Alabama

Video