Last night most of the severe weather stayed to the North near Meridian and Columbus. Jackson's atmosphere sounding at 6pm last night labeled a good opportunity for severe activity, but Slidell's sounding showed a nice cap keeping convection from growing within thunderstorms. This limited the severe activity South of Hwy 98 because this clearly made a difference in what transpired with the frontal passage. Covington and Jones Counties saw a couple cells move through that knocked down some trees as well as producing golf ball sized hail.
Helicity values were very high last night, which showed decent upper-level rotation in most of the thunderstorms last night, but we were limited by the cap. The cap acts like a bottle top keeping anything from getting out. This is what happened with the rising air.
This was a very unique event to work through last night, but, of course, every event is different and always fun to look research.