2011 Tuscaloosa–Birmingham tornado
A flattened residence in Concord, Alabama after the EF4 tornado
Meteorological history
Duration1 hour, 31 minutes
FormedApril 27, 2011, 4:43 p.m. CDT (UTC−05:00)
DissipatedApril 27, 2011, 6:14 p.m. CDT (UTC–05:00)
EF4 tornado
on the Enhanced Fujita scale
Highest winds190 mph (310 km/h)
Overall effects
Fatalities64 (+8 indirect)
Injuries1,500+
Damage$2.4 billion (2011 USD)
Areas affectedTuscaloosa to Birmingham, Alabama, United States
Part of the 2011 Super Outbreak and Tornadoes of 2011

A violent, high-end EF4 multiple-vortex tornado destroyed portions of Tuscaloosa and Birmingham, Alabama, as well as smaller communities and rural areas between the two cities, during the late afternoon and early evening of April 27, 2011. It is one of the costliest tornadoes on record. It was one of the 360 tornadoes in the 2011 Super Outbreak, the largest tornado outbreak in United States history. The tornado reached a maximum path width of 1.5 miles (2.4 km) during its track through Tuscaloosa, and once again when it crossed I-65 north of Birmingham, and attained estimated winds of 190 mph (310 km/h) shortly after passing through the city. It then went on to impact parts of Birmingham at high-end EF4 intensity before dissipating. This was the third tornado to strike the city of Tuscaloosa in the past decade, and the second in two weeks.

Meteorological synopsis

Day 1 convective outlook on April 27, 2011.

On April 23, the Storm Prediction Center (SPC) began monitoring the potential for a substantial severe weather outbreak in the extended range.[1] As a shortwave trough tracked across portions of the Mid-South and southeastern United States, moderate instability and strong wind shear ahead of a trailing cold front was expected to promote the development of supercell thunderstorms capable of producing tornadoes, large hail, and damaging winds.[2] Two days before the event, on April 25, the SPC issued a moderate risk of severe weather encompassing portions of central and eastern Kentucky, middle and eastern Tennessee, northeast Mississippi, central and northern Alabama, and northwest Georgia. Due to the combination of rich low-level moisture, strong shear, and focused large-scale ascent, there was relatively high confidence across the outlined area for strong tornadoes – a tornado rated EF2 or higher on the Enhanced Fujita scale – and widespread damaging winds.[3] By the morning of April 27, the SPC upgraded to a high risk of severe weather,[4] noting that a dangerous tornado outbreak capable of producing several violent – EF4 tornado or stronger on the Enhanced Fujita scale – and long-track tornadoes was expected.[5][6]

Shortly before 12:00 p.m. CDT, the probability of tornadoes within 25 miles of a location was increased even further to 45%, a level exceeding even typical high risk standards, for an area including Tuscaloosa. The forecast continued to emphasize the risk of strong/violent and very damaging tornadoes, as confidence increased even further regarding the risk for an extreme, high-end tornado outbreak. Throughout the afternoon hours, in the wake of two earlier mesoscale convective systems, the airmass across western and northern portions of Alabama began to quickly destabilize, with mixed layer convective available potential energy (CAPE) estimated in the 2500–4000 j/kg range and low-level dewpoints of 70–72 °F (21–22 °C) surging northward from Louisiana. Meanwhile, the wind shear environment became substantially more favorable as an 80–100 kn mid-level jet ejected eastward into the region.[5] At 1:45 p.m. CDT (18:45 UTC), a Particularly Dangerous Situation (PDS) tornado watch was issued for much of Alabama, northwest Georgia, southeast Mississippi, and southern middle Tennessee, with a >95% probability of at least two tornadoes and one or more strong tornadoes.[7] Shortly thereafter, at 3:09 p.m. CDT (20:09 UTC), the National Weather Service office in Jackson, Mississippi issued the first tornado warning on the supercell that would eventually produce the Tuscaloosa–Birmingham tornado.[8]

Tornado summary

Radar reflectivity and velocity images of the supercell that produced the tornado at 5:12 p.m. CDT (22:12 UTC) as it struck Tuscaloosa, with a debris ball clearly visible.

The supercell produced a large wedge tornado in rural Greene County, Alabama, which tracked towards the adjacent Tuscaloosa County at EF2 intensity, uprooting numerous trees and causing minor damage to structures. Near Union at 4:50 p.m. CDT, footage of the wedge tornado was captured by meteorologist John Oldshue during a storm chase for Birmingham ABC affiliate WBMA-LD/WCFT-TV/WJSU-TV (channels 58, 33, and 40 – "ABC 33/40"), which broadcast Oldshue's live video of the tornado as he was tracking it outside of town. This was the first video evidence that the tornado had touched the ground; the video, along with NEXRAD evidence of a tornado debris signature, prompted the National Weather Service office in Birmingham to declare a tornado emergency. Rapidly intensifying, the tornado moved towards the southern and eastern portions of Tuscaloosa at around 5:10 p.m. CDT (22:10 UTC).[9][10] Skycams operated by Tuscaloosa-based television station WVUA-CA (channel 7) as well as Birmingham Fox affiliate WBRC (channel 6) and ABC 33/40, and a ground-based camera crew with CBS affiliate WIAT (channel 42) captured video of the tornado as it struck Tuscaloosa. The ABC 33/40 feed was periodically disrupted due to power outages caused by wind damage to electrical transformers. As it entered the city, Skycam footage showed surface condensation in the tornado, outside of a visible debris cloud, had briefly lifted; a discernible wedge-shaped condensation funnel, with occasional horizontal and vertical subvortices, subsequently touched back down at the surface as it began moving into neighborhoods in southern Tuscaloosa.

The destroyed Chastain Manor apartment complex near Alberta City, Tuscaloosa. The complex was later rebuilt.[11]

The tornado entered the southern portion of Tuscaloosa as a low-end EF4 and crossed 35th Street, completely destroying a cell phone tower and several warehouses in an industrial area. It passed within a half mile of the Tuscaloosa Police Department Headquarters, forcing the evacuation of the dispatch personnel from the third floor offices until the storm passed. At that same time, the Tuscaloosa County Emergency Management Office sustained a direct hit and was totally destroyed along with most of their equipment and vehicles but with no injuries to the staff present.[12] The tornado then ripped through the neighborhoods of Rosedale and Forest Lake, leveling and sweeping away numerous poorly-anchored homes. Several apartment complexes were entirely destroyed in this area, and a few two-story apartment buildings were completely reduced to rubble. The tornado crossed the intersection of 15th Street and McFarland Boulevard, and numerous businesses and restaurants near the University Mall were completely flattened at low-end EF4 strength, and vehicles were either tossed around or destroyed.[10] The nearby Cedar Crest subdivision was devastated as numerous block-foundation homes were leveled. The tornado maintained its strength as it continued through the neighborhood of Alberta City, leveling and sweeping away numerous block-foundation homes, and completely flattening two more apartment buildings and a shopping center along University Boulevard.[10] As the tornado exited the Alberta City section, the Chastain Manor Apartments (which were nailed, rather than bolted to their foundations) were completely destroyed and partially swept away. A well-anchored clubhouse on the property was mostly swept away and its remains were scattered into a pond, even though the structure had lacked interior walls. A nearby manhole cover was removed from its drain and thrown into a ravine.[10][13][14]

The tornado then grew from 0.5 to 1 mile (0.80 to 1.61 km) wide and ripped through the suburb of Holt, leveling and sweeping away homes while still at low-end EF4 strength. Every tree was snapped in this area, including those within deep ravines. As it crossed Hurricane Creek, it tore apart a large metal railroad trestle, and a 34-tonne (74,957 lb) metal truss support structure was thrown 100 ft (30 m) up on a nearby hill. A marina on Holt Lake was significantly impacted, with numerous boats and a restaurant destroyed; some boats were tossed over 330 feet (100 m) in this area.[10][13][14][15] The tornado exited the Tuscaloosa area and weakened to low-end EF3 status while contracting back to .5 miles (0.80 km) wide. It continued through a dense forest towards Birmingham, this time downing thousands of trees and flattening more rural homes. Numerous trees were completely denuded and debarked as the tornado passed near the rural communities of Searles and Mud Creek, and debris from Tuscaloosa was reported to be falling from the sky across Birmingham over 20 miles (32 km) away in Jefferson County. A total of 44 people were killed in the Tuscaloosa area.[10][13][16][17]

Major damage to homes and apartment buildings in the Birmingham neighborhood of Pratt City.

After causing massive timber damage in rural areas, the tornado entered Jefferson County and rapidly intensified to its maximum intensity and width. Many stations, including WIAT, the WBMA trimulcast, CBS affiliate WTVY (channel 4) in Dothan and NBC affiliate WSFA (channel 12) in Montgomery, showed television cameras capturing the event as the tornado – which appeared wider than its estimated width during that section of the path as the condensation funnel was partially obscured by a debris cloud and a dense rain shaft – moved east-northeast across the western and northern suburbs of Birmingham at high-end EF4 strength around 6:00 p.m. CDT (23:00 UTC). Several suburbs in the area sustained catastrophic damage from the tornado as it tore through the west side of Birmingham, resulting in twenty fatalities. The suburbs of Concord, Pleasant Grove, and McDonald Chapel, along with residential areas in northern Birmingham itself, were devastated. Extensive wind-rowing of debris was noted in Concord and Pleasant Grove, numerous trees were debarked, and some homes were swept away (though much of the debris remained next to the foundations and was not scattered, and most vehicles were not moved more than 15 yards (14 m)). As the tornado moved across a coal yard in this area, a 35.8-tonne (78,925 lb) coal car was thrown 391 ft (119 m) through the air. Past the coal yard, the tornado weakened to EF2 intensity, but still was able to destroy numerous pier and beam foundations homes and several industrial warehouses in McDonald Chapel.[17] A four-sided brick home in the area also had its roof torn off, but none of its exterior walls collapsed. Numerous homes, apartment buildings, and a large church sustained significant damage as the tornado entered Birmingham's city limits and impacted the neighborhood of Pratt City. Vehicles were also moved, albeit only several feet. The tornado then struck the suburb of Fultondale, damaging homes and businesses in town. Light poles were damaged along Interstate 65, and a Days Inn and several other commercial buildings sustained major damage along US 31 before the tornado began to rapidly narrow and weaken. Some additional EF0 to EF1 damage occurred before the tornado dissipated two miles north of Tarrant. A total of 20 people were killed throughout Birmingham and its surrounding suburbs.[10][18]

Cleanup in Tuscaloosa's Cedar Crest neighborhood in May (U.S. Army Corps of Engineers photo)

The National Weather Service determined the path length of this violent tornado to be 80.68 miles (129.84 km) with a maximum damage path width of 1.5 miles (2.4 km), or 2,600 yards (2,400 m). The final rating of this tornado was a source of controversy, as some survey teams concluded EF5 damage, while others did not.[19] The structures that were swept away by this tornado were either improperly anchored, lacked interior walls, or were surrounded by contextual damage not consistent with winds exceeding 200 mph (320 km/h), and as a result an EF5 rating could not be applied. Therefore, it was given a final rating of high-end EF4, with winds estimated at 190 mph (310 km/h). Early reports indicated 65 people were killed, with over 1,000 injured. However, this was revised to 64 deaths and more than 1,500 injuries.[10][20][21][22] President Barack 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 had "never seen devastation like this." He stated further that he had already declared a federal state of emergency in Alabama.[23]

Aftermath

By the time the tornado lifted northeast of Birmingham, it had left behind a path of destruction of 80.68 miles (129.84 km) through Greene, Tuscaloosa and Jefferson counties. The tornado killed 64 people, including six University of Alabama students.[24] It caused approximately $2.4 billion of property damage, surpassing the 1999 Bridge Creek–Moore tornado as the costliest single tornado in United States history at that time. Less than a month later, however, this number was surpassed by the Joplin, Missouri EF5 tornado, which caused $2.8 billion in damage.

The effects of the tornado arguably contributed to a decrease in affordable housing in what has been called "an uneven recovery" for Tuscaloosa.[25]

See also

References

  1. ↑ Steve Goss (April 23, 2011). "Day 4-8 Severe Weather Outlook Issued on Apr 23, 2011". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  2. ↑ Steve Goss (April 24, 2011). "Day 4-8 Severe Weather Outlook Issued on Apr 24, 2011". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  3. ↑ Steve Goss (April 25, 2011). "Apr 25, 2011 0730 UTC Day 3 Severe Thunderstorm Outlook". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  4. ↑ Ryan Jewell (April 27, 2011). "Apr 27, 2011 1200 UTC Day 1 Convective Outlook". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  5. 1 2 Ariel Cohen; Richard Thompson (April 27, 2011). "Apr 27, 2011 1300 UTC Day 1 Convective Outlook". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  6. ↑ Ariel Cohen (April 27, 2011). "Public Severe Weather Outlook". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  7. ↑ John Hart (April 27, 2011). "Particularly Dangerous Situation (PDS) Tornado Watch 235". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved December 7, 2013.
  8. ↑ "Tornado warning". National Weather Service in Jackson, Mississippi. Iowa Environmental Mesonet National Weather Service. April 27, 2011. Retrieved December 7, 2013.
  9. ↑ Francis, Enjoli; Hubbard, Jeremy; Tanglao, Leezel (April 27, 2011). "Storms, Tornadoes Leave Dozens Dead in Alabama, Mississippi, Georgia and Tennessee". ABC News. Archived from the original on April 28, 2011. Retrieved April 28, 2011.
  10. 1 2 3 4 5 6 7 8 "Tuscaloosa-Birmingham EF-4 Tornado April 27, 2011". National Weather Service in Birmingham, Alabama. National Oceanic and Atmospheric Administration. 2011. Retrieved July 15, 2013.
  11. ↑ Chastain Manor
  12. ↑ "Tuscaloosa-Birmingham Tornado - April 27, 2011".
  13. 1 2 3 Jim LaDue; Tim Marshall; Kevin Scharfenberg (2012). "Discriminating EF4 and EF5 Tornado Damage" (PDF). National Weather Service Office in Norman, Oklahoma. National Oceanic and Atmospheric Administration. Retrieved June 26, 2013.
  14. 1 2 "Archived copy" (PDF). Archived from the original (PDF) on December 25, 2013. Retrieved December 25, 2013.{{cite web}}: CS1 maint: archived copy as title (link)
  15. ↑ Marshall, Tim. "Damage Survey of the Tuscaloosa-Birmingham Tornado on April 27, 2011" (PDF). AMS. AMerican Meteorological Society. Retrieved December 24, 2013.
  16. ↑ "THE AFTERMATH: Staff accounts of the tornado". Tuscaloosa News. April 27, 2011. Retrieved July 15, 2013.
  17. 1 2 McCaul, Eugene W.; Knupp, Kevin R.; Darden, Chris; Laws, Kevin. Extreme damage incidents in the 27 April 2011 tornado superoutbreak (PDF).
  18. ↑ Ballisty, Tim; Dolce, Chris; Erdman, Jonathan (April 27, 2011). "Severe Weather: Track the Storms". Weather.com. Archived from the original on May 10, 2011. Retrieved April 27, 2011.
  19. ↑ "Archived copy" (PDF). Archived from the original (PDF) on February 20, 2013. Retrieved July 22, 2013.{{cite web}}: CS1 maint: archived copy as title (link)
  20. ↑ "Event Details". National Climatic Data Center. Retrieved December 28, 2013.
  21. ↑ "Event Details". National Climatic Data Center. Retrieved December 28, 2013.
  22. ↑ "F4 Tornado - Fujita Scale". factsjustforkids.com. Retrieved July 11, 2019.
  23. ↑ Eyder Peralta (April 29, 2011). "Obama In Tuscaloosa: 'I've Never Seen Devastation Like This'". National Public Radio. Corporation for Public Broadcasting. Archived from the original on May 2, 2011. Retrieved April 29, 2011.
  24. ↑ Grayson, Wayne (May 4, 2011). "Six UA students included in list of tornado deaths". The Tuscaloosa News. Retrieved June 19, 2013.
  25. ↑ Elliott, Debbie. "'Day You'll Never Forget': Decade After Deadly Tuscaloosa Tornado, Recovery Is Uneven". NPR. NPR. Retrieved December 2, 2021.
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