Why has Ida flattened houses that survived Katrina?

Jon Lawson

Hurricane Ida has caused extensive damage across the Eastern US seaboard, in some areas uprooting trees and pulverising property which survived Katrina in 2005.  

Jay Titlow, WeatherFlow Network's Chief Meteorologist reckons he knows why. The company has a network of sensor stations dotted around the area sending useful local data back to be processed. Titow explains, “The broadening of the storm brought widespread hurricane conditions into New Orleans, with our Bayou Bienvenue station reporting 86 mph winds gusting to near 100 mph on the east side of the city. The storm winds covered a wide area, with more than 150 home-based Tempest weather stations over a 350 mile wide area measuring winds of 40 mph or more.”

As the storm wore on, Titow, based at the company’s storm operations centre, made an unusual observation. “We noticed something odd happening. As the storm came off the Bayou for its second landfall near Houma in Louisiana, the eyewall was no longer packing its previous winds, rather we were observing hurricane force winds in excess of 100 mph in a second, larger eyewall at our weather stations in Dulac and Galliano that flanked the storm. We were also seeing some very destructive gusts in excess of 130 mph.”

This is unusual as these conditions are usually only found with hurricane intensification processes over warm ocean waters, not over land. The company added in a statement, “Hurricane Ida has now been identified as the fifth-largest hurricane to ever make landfall in the US and contributes to the increasing body of evidence that we are seeing a pattern of bigger, more powerful storms driven by climate change.”