A closer look at individual tornadoes and severe weather events, covering the storm, the setup, and the aftermath.
April 27, 2011, Greene, Tuscaloosa, and Jefferson Counties, Alabama
Rating
EF4 (high-end)
Peak Winds
190 mph
Path Length
80.7 miles
Max Width
1.5 miles
Time on Ground
1 hr 31 min
Fatalities
65
Injuries
1,500+
Damage
$2.4 billion
On the afternoon of April 27, 2011, a long-track, high-end EF4 tornado touched down in Greene County, Alabama and tracked northeast for more than 80 miles across west-central Alabama, cutting directly through the city of Tuscaloosa before continuing into the Birmingham metro area. At its widest, over Tuscaloosa itself, the damage path measured about 1.5 miles across.
It's one of the most thoroughly documented tornadoes in U.S. history. Multiple Birmingham television stations, including ABC 33/40, carried it live for over an hour, and it was filmed at close range by dozens of storm chasers and residents as it moved through populated neighborhoods in broad daylight. It remains the third-deadliest single tornado in Alabama history and was, at the time, the costliest tornado in U.S. history.
The Tuscaloosa-Birmingham tornado was one of over 350 confirmed tornadoes produced by the 2011 Super Outbreak (the largest tornado outbreak ever recorded), which struck the South and East over three days, April 25–28. The Storm Prediction Center recognized the potential for a major, life-threatening outbreak days in advance and issued a rare High Risk designation for April 27.
That afternoon, a powerful upper-level trough moved across the Deep South, overriding a very moist low-level southerly flow off the Gulf of Mexico. The result was an atmosphere with both extreme instability (CAPE around 2,500–3,000 J/kg) and extreme wind shear (storm-relative helicity exceeding 500 m²/s²) stacked on top of each other, a combination meteorologists have since described as among the most favorable for violent, long-track tornadoes ever documented.
Official radar reflectivity imagery and post-storm damage survey data from the National Weather Service, used to determine the tornado’s final rating.
View all on Stormviewer2011 Tuscaloosa/Piedmont, AL Supercell Radar Loop, via Peter Corman
Tuscaloosa Tornado Radar Loop, 4/27/11, via vtruss8
4/27/11 - Tuscaloosa Tornado
The Super Outbreak of April 27, 2011: A Case Study (Convective Chronicles)
James Spann's live ABC 33/40 coverage as the tornado moved through Tuscaloosa
Tower camera footage of the tornado moving through Tuscaloosa
Faces of the Storm: a WVUA 23 & Center for Public Television documentary