[image-114][image-132]GPM Measured Tropical Storm Adjali's Rainfall Before Dissipation
Moderate rainfall was occurring around the center of Tropical Storm Adjali before it dissipated, according to data from NASA and the Japan Aerospace Exploration Agency's Global Precipitation Measurement or GPM satellites.
Adjali became the first named storm of the Southwest Indian Ocean 2014/2015 cyclone season when it formed on November 16, 2014. Adjali became a strong tropical storm the next day and just two days later started to dissipate.
The GPM observatory captured data on Adjali's rainfall rates on Nov. 18. GPM's Microwave Imager (GMI) instrument is similar to the Tropical Rainfall Measuring Mission's (TRMM's) Microwave Imager (TMI) which also provide rainfall rates of storms, but TRMM is limited to the tropics while GPM provides near real time global coverage of precipitation.
When GPM flew over Adjali on November 18, 2014 at 0726 UTC (2:26 a.m. EST), GPM's Microwave Imager (GMI) instrument collected data on the rate in which rainfall was occurring. GMI data showed that rain was falling at a rate of over 69 mm/about 2.7 inches per hour near the center of the tropical storm.
To create a total picture of the storm, the GPM rainfall data was combined with a visible/infrared image of Adjali's clouds as seen from Europe's METEOSAT-7 on November 18, 2014 at 0730 UTC. That image was created at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
Late on Nov. 19 the atmospheric conditions around Tropical Cyclone Adjali became hostile as wind shear increased and tore the storm apart. At 2100 UTC (4 p.m. EST) the Joint Typhoon Warning Center (JTWC) issued their final bulletin on the storm. At that time, Tropical Cyclone Adjali was centered near 13.3 south latitude and 70.0 east longitude, about 400 nautical miles south-southwest of the island of Diego Garcia. It was moving to the west-northwest at 4 knots (4.6 mph/7.4 kph) and had maximum sustained winds near 35 knots (40 mph/64 kph). The JTWC noted at that time that "Adjali is currently dissipating under hostile conditions."
By November 20, Adjali had dissipated in the Southern Indian Ocean putting an end to the first tropical cyclone of the Southern Indian Ocean season.
Global Precipitation Measurement (GPM) is an international satellite mission that will set a new standard for precipitation measurements from space, providing the next-generation observations of rain and snow worldwide every three hours. The GPM mission data will advance our understanding of the water and energy cycles and extend the use of precipitation data to directly benefit society. For more information about GPM, visit: www.nasa.gov/gpm
Harold F. Pierce / Rob Gutro
SSAI/NASA Goddard Space Flight Center
[image-69]Nov. 19, 2014 - NASA Sees Tropical Storm Adjali Making the Curve
Tropical Storm Adjali started curving to the southwest on its trek through the Southern Indian Ocean when NASA's Aqua satellite passed overhead on Nov. 19.
The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite captured a visible picture of Tropical Storm Adjali on Nov. 19 at 9:05 UTC (4:05 a.m. EST). The MODIS image showed that the storm began curving to the southwest, and despite slight weakening, thunderstorms circled around the low-level center.
Adjali was curving to the southwest as it continued to move along the extreme southwestern edge of an equatorial ridge (elongated area) of high pressure, located northeast of the storm. Over the next day, forecasters at the Joint Typhoon Warning Center (JTWC) expect Adjali to turn to south-southwest as a subtropical ridge (another elongated area of high pressure) builds to the storm's south and takes over steering the storm on a more southwesterly path.
By 9:00 UTC (4 a.m. EST) on Nov. 19, Adjali's maximum sustained winds had dropped to 55 knots (92.8 mph/102 kph) as a result of increased wind shear. Adjali was centered near 13.0 north latitude and 70.5 east longitude. That's about 362 nautical miles (200 miles/322 km) south-southwest of Diego Garcia. Adjali was moving to the northeast at 7 knots (8 mph/13 kph).
The JTWC forecast noted that the combined effects of increasing vertical wind shear (it's between 10 and 20 knots/11.5 to 23.0 mph/18.5 to 37.0 kph now), cooler sea surface temperatures in the path of the storm and limited outflow (winds the push out from the top of the storm) will weaken the system and cause its demise over open ocean in three days.
NASA's Goddard Space Flight Center
Nov. 18, 2014 - NASA Sees Tropical Cyclone Adjali Develop a Tail
When NASA's Terra satellite passed over the Southern Indian Ocean, the MODIS instrument aboard captured a picture of Tropical Cyclone Adjali that showed it developed a "tail," which is actually band of thunderstorms extending south of the center.
The Moderate Resolution Imaging Spectroradiometer, or MODIS instrument that flies aboard NASA's Terra satellite took a visible picture of Tropical Storm Adjali on Nov. 18 at 05:35 UTC (12:35 a.m. EST). The MODIS image showed a concentration of strong storms around the center of Adjali's circulation and a band of thunderstorms extending south of the center, resembling a "tail."
On Nov. 18, the Joint Typhoon Warning Center (JTWC) noted that bands of thunderstorms spiraling into the low-level center appeared to be weakening on microwave satellite imagery.
By 0900 UTC (4 a.m. EDT), Adjali's maximum sustained winds were near 60 knots (69/0 mph/111 kph). It was centered near 11.2 south latitude and 70.0 east longitude, about 279 nautical miles (321.1 miles/516.7 km) southwest of Diego Garcia. Diego Garcia is an island in the central Indian Ocean, and is part of the British Indian Ocean Territory.
Adjali had changed directions since Nov. 17 and was now moving to the southwest at 9 knots (10.3 mph/16.6 kph). Forecasters at JTWC now expect the storm to maintain intensity or slightly weaken over the next day. After that time, JTWC forecasters expect Adjali to weaken to a depression as it moves through cooler waters.
NASA's Goddard Space Flight Center
Nov. 17, 2014 - NASA Sees the Southern Indian Ocean Cyclone Season Awaken
The first tropical cyclone of the Southern Indian Ocean cyclone season has formed over 300 miles from Diego Garcia. When NASA-NOAA Suomi NPP satellite passed over Tropical Storm Adjali the VIIRS instrument aboard took a visible picture of the storm that showed bands of thunderstorms wrapped around its center.
NASA-NOAA's Suomi NPP satellite passed over Tropical Storm Adjali on Nov. 17 at 09:56 UTC (4:56 a.m. EDT) and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard captured a visible picture of the storm. The VIIRS image showed that the storm appeared to be coming together as circulation improved and bands of thunderstorms have been wrapping into the low-level center of circulation.
The Joint Typhoon Warning Center (JTWC) noted that animated multispectral satellite imagery showed bands have wrapped tightly into a defined, low-level circulation center with a slight, cloud filled, eye feature.
On Nov. 17 at 0900 UTC (4 a.m. EDT), Adjali's maximum sustained winds were near 55 knots (92.8 mph/102 kph). It was centered near 9.25 south latitude and 67.3 east longitude, about 334 nautical miles southeast of Diego Garcia. Diego Garcia is an island in the central Indian Ocean, and is part of the British Indian Ocean Territory.
Adjali was moving to the east-southeast at 3 knots (3.4 mph/5.5 kph). Forecasters at JTWC expect the storm to continue intensifying and turn to the southwest. However, it is expected to weaken before approaching La Reunion Island around Nov. 22 once it encounters cooler waters.
NASA's Goddard Space Flight Center