Storm Surge/Tide — Lower Terrebonne, Louisiana

2008-09-11 to 2008-09-14 · Lower Terrebonne, Louisiana

Event narrative

Storm surge flooding of 5 to 8 ft above normal caused widespread flooding in lower Terrebonne Parish. Several local drainage levees were overtopped or breached and parish officials reported 2500 structures out of the 15000 stuctures in the area flooded. The high water took several weeks to drain from the region.

Wider weather episode

Hurricane Ike emerged into the southeast Gulf of Mexico as a category 1 hurricane on September 9th after earlier being a major hurricane as it moved across the Caribbean. Ike gradually intensified and developed an unusually large wind field as it tracked northwest across the Gulf over the next three days. Ike made landfall as a category 2 hurricane during the early morning hours on September 13th along the northern end of Galveston Island, Texas. Mainly tropical storm force wind gusts associated with Ike affected southeast Louisiana although sustained tropical storm winds were measured near the coast. The main effect of Ike on southeast Louisiana was the storm surge which inundated sections of the coast, especially Terrebonne and Lafourche Parish.

A storm surge ranging from 4 to nearly 8 feet above normal along the southeast Louisiana coast with a storm surge around 5 feet above normal in Lake Pontchartrain. The unusually high storm surge generated by the distant hurricane affected many low-lying coastal areas as well as areas around Lake Pontchartrain, but federal levees protected most of the high density population areas of greater New Orleans. Some locally built levees were breached or overtopped, most notably in southern Terrebonne Parish where 2,500 homes out of the 15,000 homes in the affected area were flooded. In southern Jefferson Parish from Lafitte and Crown Point to Grand Isle, approximately 2,500 structures were flooded. Considerable storm surge flooding was noted around Lakes Pontchartrain and Maurepas. Around 200 structures were flooded in St Tammany Parish from Slidell to Mandeville and Madisonville. The storm surge flooding took several weeks to fully drain from many low lying areas of southeast Louisiana. Louisiana Economic Development office estimated that Ike caused insured and uninsured property damage of at least $3.5 billion in the state of Louisiana.

The highest wind gust recorded in southeast Louisiana was 69 mph at the New Orleans Lakefront Airport ASOS site during a squall while the highest sustained wind of 55 mph was recorded at the Pilot's Station East CMAN site near Southwest Pass; however, due to the failure of equipment at some observation sites during the storm higher winds may have occurred. The minimum sea level pressure measured in southeast Louisiana was 1002.5 millibars at LUMCON facility near Dulac. Rainfall across the area was mainly less than one and a half inches.

Source: NOAA Storm Events Database, event_id 137064. Narrative written by the NWS forecast office that issued the report.