NASA's TRMM spacecraft observed this view of Hurricane Gustav on August 27, 2008 as it attacked Haiti. At this time the storm was a category 1 hurricane with sustained winds of 65 knots (75 mph) and a pressure reading of 992 millibars. The cloud cover is taken by TRMM's Visible and Infrared Scanner(VIRS) and the GOES spacecraft. The rain structure is taken by TRMM's Tropical Microwave Imager (TMI) and TRMM's Precitation Radar(PR) instruments. TRMM looks underneath of the storm's clouds to reveal the underlying rain structure. Blue represents areas with at least 0.25 inches of rain per hour. Green shows at least 0.5 inches of rain per hour. Yellow is at least 1.0 inches of rain and red is at least 2.0 inches of rain per hour.
If we remove the clouds, we can see Gustav's rain structure. Rain is the fuel that drives these storms. The blue region represents areas where the storm is dumping at least 0.25 inches of rain per hour. Green is 0.5 inches of rain per hour, yellow is 1.0 inches of rain and red is 2.0 inches of rain per hour.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 220.127.116.11.0