Record U.S. Tornado Outbreak Anniversary

Where were you four years ago? Meteorologists remember...

Today, we are marking the anniversary of the conclusion of the largest continuous tornado outbreak in U.S. history. April 25-28, 2011 is etched in brains of forecasters around the country. It was an incredible time to be a university student in a meteorology program, as I was that year. That is like being a caveman when your cave-neighbor invented the wheel – minus the enthusiastic grunting. Most college majors use their text books extensively, and meteorology isn’t that different. We probably used our calculator more than most, but to have a real-life situation play out in front of us, and the ability to interpret what was happening on a micro-, meso-, and synoptic scale was incredible. Our professors, love them to death but they were as excitable as an oak tree, threw the text away for a month or so.


Doppler image of Tuscaloosa tornado: velocity (left) and reflectivity (right)

I won’t go into the atmospheric dynamics that were in place, but it was loaded. It had all four ingredients, and plenty of it; wind shear, lift, instability, and moisture. Things started to heat up on the 25th of April, and forecasters kept looking downstream, and those atmospheric conditions weren’t changing for the better. The statistics from the four day event were staggering, something never seen before; 355 confirmed tornadoes, 348 fatalities, and over $11 billion in damage.

April 27th, by itself, was something that made weather offices in the southeast look more like a battle zone than a rudimentary office building. There were 292 tornado reports on that day alone, which includes verified and unverified twisters. This is what that one day looked like graphically for the southeast, red being tornado warnings. One. Day.


Tornado warnings (red) for April 27, 2011

One of the most dangerous things about a good portion of this area is the hilly, and often tree-obscured view across the horizon. That makes things especially dangerous when these outbreaks occur. It was an extremely long four days across the southeast and one that continues to be researched by meteorologist to this day. People took a long, hard look at their response to the forecasts and now have made considerable changes to their course of action if severe weather is in the area, that includes have an iron-clad plan of what to do with the family at home.

Ironically, at this very same time last year, another outbreak was stirred up in the same general location where 84 tornadoes were confirmed and 38 people lost their lives.

This is when the weather starts to get steamy and things get active. Have a plan and don’t get caught without the forecast and a good way of getting weather information. The same thing that makes predicting the simplest of weather so hard is the same thing can get you stuck in a life-threatening situation, and that one thing is the ability for weather to change very quickly.