AUSTIN (KXAN) — This week marks the 10-year anniversary of a devastating tornado outbreak across the Deep South between April 25 and 28, 2011. This “swarm” event was responsible for over 350 tornadoes stretching from an area between Texas and New York, from Canada down to Florida.
April 27 was the deadliest and most catastrophic day when there were 216 confirmed tornado reports. Of which, 11 were EF-4s and 4 were EF-5s — the highest two rankings of damage on the Enhanced Fujita (EF) scale.
To put things in perspective, the United States averages about 1,000 tornadoes a year. However, of these reports, EF-5s only amount for less than 1%. As a matter of fact, since 1953, there have only been 59 confirmed EF-5 tornadoes. That’s an average of less than one per year.
In addition to the record number of tornadoes, the outbreak of tornadoes was responsible for 360 deaths, 316 of which were lost on April 27.
Damages from the outbreak amounted to $10.2 billion, the most ever for any tornado outbreak on record in the United States.
The morning of April 27 saw a line of thunderstorms move through Alabama and Tennessee which took out power to close to 1 million customers. Later on that afternoon is when supercell thunderstorms erupted and led to several EF-4 and EF-5 tornadoes ravaging the same areas, leaving hundreds of thousands of people without warning.
2011 Tornado Outbreak Statistics