File:Flooding in Louisiana (MODIS 2021-09-03).jpg

English: Hurricane Ida slammed into the United States on August 29, 2021, coming ashore at Port Fourchon, Louisiana with sustained winds of 150 miles per hour (240 km/h). This tied two other hurricanes—Hurricane Laura (2021) and an 1856 storm—for the strongest landfall on record in the state of Louisiana. After battering Louisiana with wind and water, Ida travelled across northern Mississippi, the Tennessee Valley, and part of West Virginia, finally weakening to a post-tropical remnant on September 1. Even as a remnant, Ida packed a devastating punch. As it stormed across Virginia, Maryland, New Jersey, Pennsylvania, and New York, Ida’s remnants spawned tornadoes, doused the region with torrential rains, and caused severe flooding. As of September 2, Ida has claimed more than 40 lives—most of those in the Northeast.

While the Northeast was feeling the wrath of Ida, Louisiana continued to struggle with the aftermath of a direct hit of the vicious hurricane. The wind was only the first chapter of the tragic trilogy written by the catastrophic storm. Storm surge and torrential rain were chapter two and three. While the wind left severe destruction, it passed on relatively quickly. The inundation and flooding along the Gulf Coast, while less dramatic, has been slow to abate.

On September 2, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Terra satellite acquired a false color image illustrating massive flooding in southeastern Louisiana. This type of image uses short-wave infrared, infrared, and red light to help contrast water and vegetation. Here, vegetation appears bright green while water looks deep blue. Cloud appears white, except high, cold clouds which are tinted light blue. Vegetated area that is saturated with water may appear darker green than the surrounding dryer vegetation.

It’s clear from this single image that much of the region remains significantly flooded from Hurricane Ida’s rains and storm surge. To really understand the extent of the inundation, however, it’s best to compare with a pre-hurricane image of the same area. Thanks to the NASA Worldview App, it’s easy to view a comparison with the same area on August 5, prior to the flood, by clicking here.