TRMM Sees Severe Weather

The TRMM satellite flew over the southeastern United States on April 7, 2014 at 1300 UTC (9:00 AM EDT) when a line of intense thunderstorms was moving through the area. Tornado watches were in effect over much of the area. A possible tornado, associated with the same weather system, caused destruction and injuries when it moved through southern Mississippi earlier at about 2 AM EDT. TRMM's Precipitation Radar (PR) data revealed that rain was falling at a rate of over 130mm/hr (about 5.1 inches) in one severe thunderstorm near the Alabama and Florida panhandle border. A radar reflectivity value

GPM in Final Orbit, DPR Calibration Continues

The Global Precipitation Measurement mission's Core Observatory is performing normally. On April 2, the GPM Core Observatory fired its thrusters for an 80-second delta-V burn that accelerated the spacecraft and circularized its orbit. The Core Observatory is now flying in its final orbit, 253 miles (407 kilometers) above Earth's surface. Calibration of the Dual-frequency Precipitation Radar (DPR) and GPM Microwave Imager (GMI) continued. On March 30 and 31, additional DPR external calibrations took place using the Active Radar Calibration site in Tsukuba, Japan. For the March 31 calibration

Tropical Cyclone Hellen's Lively Remnants

Powerful tropical cyclone Hellen rapidly weakened after hitting northwestern Madagascar but Hellen's remnants have recently started to show signs of life. The TRMM satellite flew over these remnants in the Mozambique channel on April 2, 2014 at 0143 UTC. A rainfall analysis using TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments found that some strong convective thunderstorms had developed in the area. It was revealed by TRMM PR data that rain was falling at a rate of over 75 mm/hr (almost 3 inches) in a few locations.

Core Observatory Commissioning Continues

The Global Precipitation Measurement mission's Core Observatory commissioning activities continued normally this week. Both the GPM Microwave Imager and the Dual-frequency Precipitation Radar (DPR) are collecting science data and NASA and the Japan Aerospace Exploration Agency released the first images from the instruments on March 25. The DPR's functional checkout activities and internal calibration continued. The first external calibration using the Active Radar Calibration site in Tsukuba, Japan, was performed on March 23. A 120-second "Delta-V" burn was successfully completed Wednesday

Tropical Cyclone Hellen

Tropical cyclone HELLEN formed in the Mozambique channel northwest of Madagascar on March 28, 2014. HELLEN became a very powerful tropical cyclone with peak sustained winds of 130kts (about 150 mph) on March 30, 2014. HELEN's eye came ashore in northwestern Madagascar On March 31, 2014 with winds predicted to be about 95kts (~109 mph). HELEN is now expected to gradually weaken over northwestern Madagascar while moving southwestward and be over the Mozambique Channel again on April 1, 2014. The TRMM satellite passed above HELLEN on March 30, 2014 at 1747UTC when the tropical cyclone was close