Above are images of Hurricane Katrina created from AIRS infrared and microwave observations at 1:30 AM local time on Monday, Aug

Above are images of Hurricane Katrina created from AIRS infrared and microwave observations at 1:30 AM local time on Monday, August 29, 2005 as it makes landfall on the Gulf Coast. At the time of these images, Katrina was a Category 5 storm with peak winds of approximately 150 mph. The images to the right were taken at 2:00 AM local time on August 30, 2005. The infrared image shows how the storms look through an AIRS Infrared window channel. Window channels measure the temperature of the cloud tops or the surface of the Earth in cloud-free regions. The lowest temperatures are associated with high, cold cloud tops that make up the top of the hurricane. The infrared signal does not penetrate through clouds, so the purple color indicates the cool cloud tops of the storm. In cloud-free areas, the infrared signal is retrieved at the Earth's surface, revealing warmer temperatures. Cooler areas are pushing to purple and warmer areas are pushing to red. The microwave images reveal where the heaviest precipitation in the hurricane is taking place. The blue areas within the storm show the location of this heavy precipitation. Blue areas outside of the storm where there are moderate or no clouds are where the cold (in the microwave sense) sea surface shines through. Click on image to enlarge. Credit: NASA JPL