Last night, a textbook squall line (called a quasi-linear convective system, or QLCS) marched off the coast of Texas, and moved across the northern Gulf of Mexico. The northern portion of this came ashore in southern Louisiana, and developed into what was a classic look for a strong QLCS.
The red X indicates the location of the mesoscale convective vortex, or an MCV, associated with this QLCS. An MCV is a convectively induced low pressure system that forces surface convergence, and helps to further intensify QLCS’ sometimes. The presence of this MCV indicates the strength of this system as a whole, and it was just an amazing sight to see. The storms produced damaging winds across the Gulf Coast last night, and was an amazing sight to behold on radar. And, while much weaker, the MCV is still present across eastern Alabama.
Well defined MCV near Baton Rouge with a trailing band of severe storms pic.twitter.com/g4dWZg6hrL
— James Spann (@spann) May 20, 2016
A 12-hour loop of the impressive MCS/squall line across the N. Gulf of Mexico starting at 4:35p CT. (Credit: UCAR) pic.twitter.com/9rC9sBS3a1
— Jonathan Erdman (@wxjerdman) May 20, 2016
New Orleans is about to get rocked with heavy rain and very gusty winds… as a squall line moves in !! pic.twitter.com/ESPJ7IHW2j
— Tom Moore (@TomMoorewx) May 20, 2016
— Robert MacDonald (@Rmacd24) May 20, 2016