Super Outbreak of 2011: 350 tornadoes killed 321 people

NOAA reported at least 350 tornadoes formed during the outbreak, including four rare EF-5s with winds over 200 mph.

It’s a day that will live in the minds of those in the eastern half of the nation, but especially Alabamians, forever. The 2011 Super Outbreak impacted dozen of states and became known as one of the costliest tornado outbreaks ever seen.

The multiday tornado outbreak kicked off on April 25, and during the next three days, the spring storm system impacted 26 states, killing at least 321 people and injuring thousands.

The National Oceanic and Atmospheric Administration reported at least 350 tornadoes formed during the outbreak, including four rare EF-5s with winds over 200 mph.

Most of the destruction happened on Wednesday, April 27, when atmospheric conditions came together across the South to produce ideal conditions for long-track tornadoes.

The outbreak was not a surprise to meteorologists at the Storm Prediction Center, who issued a high risk (5 out of 5) threat and placed the bull's-eye zone over northeast Mississippi, south Tennessee and northern Alabama.

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A US flag is seen next to a destroyed home in the Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27.  (MANDEL NGAN/AFP via Getty Images))

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A teddy bear is seen ontop of debris on the side of a street in the Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27. (MANDEL NGAN/AFP via Getty Images)

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A serviceman talks on the phone while standing next to fallen trees and debris in the tornado strickened Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27. Grieving storm survivors turned to prayer and the good grace of volunteers Sunday across the US south as shattered communities looked to rebuild after the second-worst tornado disaster on record.  (MANDEL NGAN/AFP via Getty Images)

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A damaged car and debris are seen in the Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27.  (MANDEL NGAN/AFP via Getty Images)

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Tornado damaged cars are seen as the sun sets in the Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27.  (MANDEL NGAN/AFP via Getty Images)

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TUSCALOOSA, AL - APRIL 30:  Volunteers search through destroyed homes on April 30, 2011 in Tuscaloosa, Alabama. Alabama, the hardest-hit of six states, is reported to have had nearly 300 deaths as a result of the storms.  (Photo by Tom Pennington/Getty Images)

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Tornado damaged trees are seen as the sun sets in the Holt neighbourhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27.  (MANDEL NGAN/AFP via Getty Images)

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A soda machine is seen in debris in the Holt neighborhood of Tuscaloosa, Alabama May 1, 2011. Many trailer homes in the area were destroyed by the tornado which struck April 27.  (MANDEL NGAN/AFP via Getty Images)

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TUSCALOOSA, AL - APRIL 28: A woman overlooks what's left of the Alberta district of Tuscaloosa on April 28, 2011 in Tuscaloosa, Alabama.  On April 27, tornados passed through the south killing more than 200 people.   (Photo by Bryan Anselm/Getty Images)

A series of squall lines produced many of the tornadoes throughout the day, but where storm cells were able to tap into the unstable environment, they produced strong, long-track tornadoes.

One of the most destructive twisters was an EF-4 that hit populated areas in Alabama that included Tuscaloosa and Birmingham.

The tornado is believed to have stayed on the ground for 80 miles and had winds around 190 mph at its peak.

Immediately after the storms, Jeff Byard, an executive operations officer for Alabama Emergency Management, said he knew the scope of the damage from unfathomable.

 "It soon became very apparent that the state could not handle the emergency alone. It will go down in history as the worst outbreak of tornadoes in Alabama," Byard said.

NASHVILLE’S SCARS STILL HEALING TWO YEARS AFTER DEADLY TORNADO OUTBREAK

The Federal Emergency Management Agency reported 247 residents in the state, and more than 23,000 homes were either damaged or destroyed.

NOAA estimated damages at roughly $12 billion, making it the costliest tornado outbreak in history.

The outbreak was one of several during April 2011 that pushed the tornado count to 751, the most ever reported during a single month.