EF1 tornado in Washington Parish, Louisiana

An EF-1 tornado with peak winds of 95 mph and max width of 200 yards entered Washington Parish from Tangipahoa Parish just northwest of the intersection of LA 1057 and LA 450. The tornado strengthened, uprooting trees and snapping large branches and the tops of trunks as it reached LA Hwy 10 and moved into Sylvest Rd. Additional tree damage was identified downstream of the surveyed end point of this tornado via high resolution satellite imagery which evidently dissipated prior to it reaching LA Hwy 16, west of Franklinton.

Environmental conditions favorable for a QLCS (Quasi-Linear Convective System) tornado event developed across southeast Louisiana and southern Mississippi during the afternoon and evening hours of March 11th. An upper-level storm system moving east from Texas overspread a very moist and increasingly unstable air mass in place across the region. At the same time, intense low-level wind shear and strong atmospheric spin developed as southerly winds strengthened ahead of an approaching line of storms with bowing segments.

The combination of rich Gulf moisture, strong low-level atmospheric spin, and a fast-moving line of thunderstorms created an environment supportive of embedded rotating circulations along the leading edge of the QLCS. As that line moved west to east across the local area, several rapidly developing tornadoes formed within these circulations. A total of 8 tornadoes were confirmed across southeast Louisiana, including 2 with path lengths exceeding 10 miles. Well over a dozen additional reports of damaging straight-line winds were also received.