TRMM News

Tropical cyclone BUNE was southeast of the Fiji Islands and close to a category one on the Saffir-Simpson scale when the TRMM satellite passed above on 24 March 2011 at 1548 UTC. TRMM Microwave Imager (TMI) and Precipitation Radar (PR) data from this pass show that large rain bands around BUNE contained numerous intense thunderstorms. BUNE is expected to peak as a category two tropical cyclone with wind speeds of about 85 kts (~98 mph) on 26 March 2011 while moving over the open waters northeast of New Zealand.

The TRMM satellite passed directly above the remnants of tropical cyclone CHERENO (18S) in the South Indian Ocean on 22 March 2011 at 0225 UTC. TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) show that CHERENO, although weakened, still had some life and was producing very heavy rainfall of over 50 mm/hr (~2 inches) south-southeast of Reunion Island.

The image above shows subtropical cyclone ARANI as the TRMM satellite passed over head on 17 March 2011 at 0958 UTC. TRMM Microwave Imager (TMI) and Precipitation Radar (PR) data from that orbit show that moderate to heavy rainfall was only occurring to the southeast of ARANI at that time. TMI and PR rainfall data were overlaid on a combination visible and infrared image that used TRMM Visible and InfraRed Scanner (VIRS) data. Visible low level clouds from this image (shown in shades of yellow) are the only evidence for the location of ARANI's center of circulation. Click here to see earlier

On 17 March 2011 at 0212 UTC the TRMM satellite passed over tropical cyclone 18S that had formed and was intensifying in the open waters of the South Indian Ocean. 18S was already well organized and TRMM's Precipitation Radar (PR) showed that powerful thunderstorm towers were located near 18S' center of circulation. These towers know as chimney clouds release a lot of energy and can serve to strengthen a tropical cyclone. 18S is expected to attain strong tropical storm intensity with wind speeds of at least 55 kts (~63 mph) in the next three days.

The TRMM satellite had another very good view of subtropical cyclone ARANI in the morning light on 16 March 2011 at 1052 UTC. This orbit showed that there were very heavy thunderstorms in the eastern half of the storm. TRMM's Precipitation Radar (PR) showed that some of these powerful storms were reaching to heights of over 14 km (~8.7 miles) above the surface of the south Atlantic Ocean.

During the daytime on Tuesday 15 March 2011 at 1820 UTC the TRMM satellite flew over a rare cyclone labeled ARANI in the south Atlantic Ocean. ARANI has the appearance of a tropical cyclone but has been classified as a subtropical cyclone. NOAA's Satellite and Information Service classified ARANI as a T1 on the Dvorak intensity scale which would indicate an estimated wind speed of about 29 kts (~33 mph). TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data were used in the image on the right to show rainfall near ARANI. Tropical cyclones are very rare in the south Atlantic Ocean. In

Although the heaviest rainfall over the past week was in the southern United States, flooding was reported in states from Louisiana to northern New York. The rainfall analysis above was made by merging precipitation data from multiple satellites. This Multisatellite Precipitation Analysis (TMPA) analysis used data products that were calibrated with TRMM precipitation data. These data products are calculated and stored at Goddard Space Flight center and are available within a few hours after being received by satellites. This analysis indicates that the greatest total rainfall for the past week

The TRMM satellite flew over tornadic thunderstorms for the second time in less than a week on 9 March 2011 at 1208 UTC ( 6:08 AM CST). By 1652Z (10:52 AM CST) NOAA had received 9 tornado sighting over Louisiana, Alabama and Florida. A precipitation analysis from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) (in the lighter swath) again showed extremely heavy rainfall near tornadic activity. TRMM's Precipitation Radar (PR) data were used in the image on the upper right to show a 3-D slice through a possible tornado.

The TRMM satellite was flying high over head when it passed above tornadoes occurring in the state of Louisiana on 5 March 2011 at 1411 UTC (8:11 AM CST). The National Oceanic and Atmospheric Administration (NOAA) reported that seven tornadoes were spotted in Louisiana on that date. These tornadoes caused at least 15 injuries and one death with a tornado that hit in the northwest section of Rayne, Louisiana. The image on the left above shows a precipitation analysis using data collected with that TRMM orbit. TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) (in the lighter swath)