Flash Flood — Lafourche, Louisiana

2024-09-11 · near Chegby, Lafourche, Louisiana

Event narrative

As the north and northeastern eyewall stretched into an east-west oriented band of heavy rainfall, training storms resulted in widespread rainfall totals of 5-7 inches across the northern half of the parish. Radar estimates indicate locally higher totals of up to 10 inches may have fallen in some areas. Much of the rain fell within a short span of only a couple hours, resulting in widespread flash flooding throughout areas such as Thibodaux, Chackbay and Kraemer. Numerous roads became impassable, 30 homes flooded, and 26 residents were rescued from their flooded homes.

Wider weather episode

Hurricane Francine formed as a tropical storm in the Gulf of Mexico on September 9, 2024, and intensified into a Category 2 hurricane before making landfall near Houma, Louisiana, on the morning of September 11. With sustained winds of 100 mph and gusts peaking at 105 mph, Francine brought widespread damage to southeastern Louisiana and southern Mississippi. A storm surge of 6-9 feet inundated low-lying coastal areas, while torrential rainfall of 10-15 inches caused significant flash flooding, including in the New Orleans metro area. Over 400,000 residents experienced power outages, and extensive wind damage was reported, with numerous trees and powerlines downed. There were a total of 6 direct injuries, 0 indirect injuries and 0 fatalities. The Louisiana Department of Health reported 18 ED visits for carbon dioxide exposure across various parishes in southeast Louisiana. In terms of dollar damage, the best estimate around $100 million but that could be very conservative as some online reports suggest much more than that.

View location on OpenStreetMap → (29.8945, -90.8345)

Source: NOAA Storm Events Database, event_id 1217857. Narrative written by the NWS forecast office that issued the report.