Intense Tropical Thunderstorms Detected by the Special Sensor Microwave Imager/Sounder

The 150-GHz microwave window channel and the three water vapor channels, 183.3 plusmn 7, 183.3 plusmn 3, and 183.3 plusmn 1 GHz of the Defense Meteorological Satellite Programpsilas (DMSP) Special Sensor Microwave Imager/Sounder (SSMIS) are used to detect intense thunderstorms over the tropics (30^deg S-30 ^deg N). This application utilizes the advantages of conical scanning and high surface horizontal resolution of the SSMIS compared to the same measurements made with cross-track scanning radiometers. The criteria to detect intense tropical thunderstorms are derived by the combination of the brightness temperature differences between the three water vapor channels and brightness temperatures at the four frequencies. One year of SSMIS data (December 2005-November 2006) is surveyed for intense tropical thunderstorms. The most intense tropical thunderstorms are predominant over land and are mainly concentrated over Central and South America, tropical west Africa, and northern Australia. Over most regions these very intense tropical thunderstorms have a strong regional dependence and a pronounced seasonal migration.