The GOES-12 satellite sits at 75 degrees west longitude at an altitude of 36,000 kilometers over the equator, in geosynchronous orbit. At this position its Imager instrument takes pictures of cloud patterns in several wavelengths for all of North and South America, a primary measurement used in weather forecasting. Every three hours the Imager takes a picture of the full disk of the Earth. This animation shows a sequence of these full disk images in the shortwave infrared wavelengths, 3.78 to 4.03 microns, during the period that Hurricane Katrina passed through the Gulf of Mexico. This wavelength band shows the day-night cycle, and is useful for identifying fog at night and discriminating between water clouds and snow or ice clouds during the daytime. Note: GOES-12 full-disk shortwave infrared imagery of Hurricane Katrina from August 23, 2005 to August 31, 2005. Data Collected: 2005-08-23T08:45Z - 2005-08-31T02:45Z. Animator: Horace Mitchell (NASA/GSFC). Scientist: Dennis Chesters (NASA/GSFC). Platforms/Sensors/Data Sets: GOES-12/Imager, GOES-12/Imager/Infrared.