NASA's TRMM spacecraft observed this view of Hurricane Alex on June 30, 2010 at 2103 UTC (5:02 PM EST). At this time, Hurricane Alex was increasing in intensity and had become a category 2 storm with estimated winds at 75 knots (~86.4 mph) and a pressure reading of 962 mb. The rain structure is taken by TRMM's Tropical Microwave Imager (TMI) and TRMM's Precitation Radar (PR) instruments. The TMI rainfall analysis shows that Alex had a well defined eye containing powerful thounderstorms that were dropping extreme amounts of rain. The clouds are taken by TRMM's visible-infrared radiometer (VIRS) and the National Oceanic and Atmospheric Administration (NOAA) Geostationary Operational Environmental Satellite (GOES-13) infrared instrument. TRMM looks underneath of the storm's clouds to reveal the underlying rain structure. The colored isosurface under the clouds show the rain seen by the PR instrument. Areas of extremely heavy rainfall are colored in red. Heavy rainfall are colored in yellow, moderate rainfall are colored in green, and light rain are in blue.
Notice an almost symmetric circle of extremely heavy rainfall at the eye when the clouds are removed. This shows that Alex had a well-defined eye containing powerful thunderstorms that were dropping extreme amounts of rain.
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 18.104.22.168.0