It happens...
It has been a interest of mine to learn more about certain weather circumstances... And it is very interesting to see just how the upper level and lower level atmospheric conditions can be set up in such a way to make the areas of Mississippi, Alabama and into Georgia, and Tennessee so favorable for strong long track tornadogenesis...
A cold upper level system that drops into western Texas, Jetstream also dropping into that area and moving into those southern states, a surface low forming in eastern Texas or eastern Louisiana, steep lapse rates with temp dropping quickly with increase in height in the atmosphere, a strong low level jet coming in from the south southeast from the Gulf of Mexico at 850 MB, and that in combination with west to southwest winds in the mid levels at 700 mb and your have great turning of wind direction with height in the atmosphere, low level dew points increasing above 65°, and if one can get some clearing skies ahead of the developing surface low pressure.... And you get what we had yesterday....
Though yesterday was mild... In comparison to April 2011 where many, many more tornadic thunderstorms happened.... 300+ people perished in a single day during that extreme large scale event. A high number of EF-4 and EF-5 tornadoes happened that day... Yesterday there were long track dangerous tornadoes for sure... Just not very many of them. The conditions yesterday were in place for some extremely bad storms. Though not very many of those type storms actually developed.
Big take aways from yesterday...
#1 it's all about the overall synoptic atmosphere set up... Remember.... It really about that... If those conditions are present then a violent EF-3 or stronger tornado can happen... and in Mississippi and Alabama especially that is what happened... 2 storms became more individualized and able to tap into those dangerous atmospheric conditions... Has I watched that unfold on the radar.... I knew that those storms were extremely strong and dangerous.
IF those storms had been and stayed apart of a uninterrupted strong thunderstorm line.... Dangerous tornadoes would very likely would not have occurred.
Only 1 percent of all tornadoes in the US get as strong or stronger than a EF-3...
Yet 98% of all tornado fatalities are from EF-3, EF-4 and EF-5 tornadoes...
But when those two storms morphed into discrete individualized storms... Then those storms could tap into the volatile atmospheric conditions much more strongly.