Generally speaking, Tornado Alley is at its most active during the late spring and early summer. The most treacherous tornadoes in Oklahoma’s history have all seem to come in the first week in May, for example. Here in 2019, however, we have been reminded that the so called “Dixie Alley” sees its busiest time in the early part of spring.
We’ve already seen the deadliest tornadoes in 6 years on March 3rd, as a twister in Beauregard, Alabama killed 23 people there alone. Earlier this week, destructive tornadoes rumbled from Franklin and Alto, Texas to Vicksburg, Mississippi.
This pattern is expected to continue in the next couple of days. There is a chance for strong thunderstorms today in the southern Plains, a bit further west than what we have seen so far, but tomorrow poses a risk for a return of severe storms, with an emphasis on tornadoes in Dixie Alley. There is an enhanced risk for severe storms from Louisiana to Georgia and the Panhandle of Florida.
The jet stream hasn’t quite retreated to Canada yet this early in the season, so surface moisture doesn’t build all the way back to the Plains. Cold air is more dense and has more momentum than warm air, so it has no problem intruding on the southeastern US, touching off the strong storms of early spring.
It will get a little bit further away, that cold air, as the summer approaches and finally arrives. The severe threat in the southeast will lessen, but the oppressive heat and humidity will certainly arrive.