5 Years Later- April 27, 2011 Severe Weather Outbreak

(For Wednesday forecast/Tuesday recap see here)
The forecast for severe weather and tornadoes in the Plains yesterday brought back terrible memories for millions of people in the Southeast yesterday as we are at the 5 year anniversary of one of the worst severe weather outbreaks in US history.  2011 featured stunning extreme weather from January through October before warm Pacific flow finally calmed things down.  This outbreak plus Joplin, Hurricane Irene and the Halloween Blizzard all made 2011 one of infamy for many.

4/27/2011 storm reports (note- the 292 tornadoes was revised to 199)

Meteorological Conditions
The severe weather outbreak began a few days earlier as tornadoes were spawned in Texas, Louisiana, Arkansas, Mississippi, Tennessee, Kentucky and some other states as early as April 24.  A series of upper level disturbances dropped a trough deep into the south.  Here is the 500 mb pattern at 7 AM on April 27

500 mb obs, winds, heights, temps 8 AM 4/27/11 (image NOAA)

Notice strong winds along the base of the trough.  Here is a composite of the 500 mb winds, 850 winds, dewpoints

The strong winds at 850 mb (red) would help turn the surface southerly flow ensuring low level rotation.  The strong 500 mb winds would help ensure long track tornadoes.  The warm moist atmosphere would ensure plenty of fuel for super cell thunderstorms.  This is a textbook set up. As the sun destabilized the atmosphere further  super cells did indeed form.  Here is a radar loop across Alabama

Birmingham radar loop 4/27/11

The severe threat continued.  At 7 PM the composite atmosphere looked like this

The result was catastrophic and ruinous.  

Impact

Here are the Southeast tornado tracks

NOAA tornado track survey April 25-28

In all 219 tornadoes formed on April 27. For the total outbreak 363 tornadoes formed from Texas to New York.  The total death toll from the event is 324 with over 2200 injuries.  For just April 27

It was an astonishing south of force from mother nature.  Here are some images of the damage.

Tuscaloosa tornado 4/27/11 (image severe studios) 

Tuscaloosa from above after tornado 

Concord, AL damage (image Atlantic)

It was also in 2011 that a strong EF-3 tornado ripped through Springfield, MA.  We are not immune from tornadoes in Southern New England.  In fact on the same day as the famous Worcester tornado of 1953 (killed 94 people) a tornado ripped through my hometown of Northbridge, MA.  Keep up with the blog and you'll be prepared.

-Zack Green