This was a less than ideal 0-3 km shear orientation for this QLCS overall, but a section of the line to the northeast of KDGX (Jackson, MS) did have a slightly more favorable orientation.

Above we see an initial NMDA detection at 2039 UTC associated with the tightening couplet. There is NTDA detection to the northwest associated with a broader cyclonic circulation that may at first looked like a developing bookend vortex, but this didn’t last given semi-discrete storm mode.

As the couplet starts to pivot anticylonically and tighten a bit, we see agreement in placement with the NMDA and the NTDA. The >20% shown in the NTDA legend refers to a slider setting to filter out lower probabilities. Having the filtering feature is great and made even better by having the legend provide that extra information.

The next available time shows accurate progression of the NTDA detection with respect to the now even better defined couplet (note: the NMDA had not updated since the previous image).

-marfafront