A line of severe weather from a developing low crossed through Kentucky, Tennessee and on into Alabama, Arkansas, Georgia, South Carolina and northern Florida on Good Friday. Several tornados were spawned apparently, but the most damaging was a twister that dropped on the city of Murfreesboro (immediately south and slightly east of Nashville) in the early afternoon.

This video shows a animated series of scan images for the region starting from about 1:30 EDT. There are three scans – short range composite, storm relative velocity, and vertical integrated liquid. In particular, there is a signature in the vertical integrated liquid scan that looks like it may be that of the Murfreesboro tornado.

The following three VIL scan excerpts were taken at 1:53pm EDT, 1:57pm EDT and 2:07pm EDT. The arrows point to structures of interest.

Vertically Integrated Liquid, Nashville 17:53UTC (1:53 pm EDT), excerpt

Vertically Integrated Liquid, Nashville 17:53UTC (1:53 pm EDT), excerpt

Vertically Integrated Liquid, Nashville 17:57UTC (1:57 pm EDT), excerpt

Vertically Integrated Liquid, Nashville 17:57UTC (1:57 pm EDT), excerpt

In this second image, the arrows point to two interesting structures. The topmost may be the signature of the tornadic supercell that spawned the Murfreesboro tornado. There seems to have been a coalescence of the two cells evident in the first image. The circular form of high reflectivity is indicative of strong rotation in this cell, a “tube” of water, as it were.

The lower arrow points also to a interesting structure – this has maintained a very high reflectivity over several minutes, and in a tight configuration. I don’t have touchdown data yet to see if either of these structures were the cells that produced the tornado.

The third image, below, shows the same cells 10 minutes later, suggesting that some dissipation had occurred in the upper cells, whereas the lower one seems to be continuing to strengthen. I will leave off the warning boxes for greater clarity on future scan series.

Vertically Integrated Liquid, Nashville, 18:07UTC (2:07pm EDT), excerpt

Vertically Integrated Liquid, Nashville, 18:07UTC (2:07pm EDT), excerpt

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