EF0 tornado in St. Tammany Parish, Louisiana

A storm likely spawned a waterspout near the northshore of Lake Pontchartrain and moved onshore as a tornado near Guste Island around 2:50 AM CDT. The tornado tracked to the north-northwest across mainly uninhabited swamp lands about two miles west of the Tchefuncte River. Sporadic softwood and hardwood tree damage was noted on the eastern shore of the inlet. Additional damage was likely but it was inaccessible during the the storm survey. The damage that was viewable from the ground survey indicates an EF-0 tornado with estimated peak winds around 75 mph.

The tornado was also confirmed by KLIX radar data with a tornado debris signature evident as it was crossing the inlet at 2:53 AM CDT. The tornado quickly lifted around 2:55 AM as it approached the northern shore of this inlet.

In the overnight hours on May 17th into the early morning on May 18th, a cluster of slow moving severe thunderstorms associated with a weak mid-level disturbance drifted east across southeastern Louisiana. Ample overnight instability and weak steering flow resulted in damaging wind gusts, flash flooding and a few isolated weak tornadoes.