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Hurricane Season 2012: Tropical Cyclone Chanda (Southern Indian Ocean)
01.10.12
 
Radar imagery from Madagascar today, January 10, 2012, shows the center Tropical Storm Chanda's remnants and most of its associated rainfall are off-shore and east of the island nation. › View larger image
On January 8, 2012 when Chanda was at tropical storm strength and was just about to make landfall in southern Madagascar, NASA's Terra satellite passed over the storm from space at 07:00 UTC (2 a.m. EST). The MODIS instrument image from Terra showed Chanda as a rounded and organized shape.
Credit: NASA Goddard MODIS Rapid Response Team
Remnants of Tropical Storm Chanda Now Past Madagascar

Radar imagery from Madagascar today, January 10, 2012, shows the center Tropical Storm Chanda's remnants and most of its associated rainfall are off-shore and east of the island nation.

The remnants of Tropical Storm Chanda currently have little chance for regeneration in the Southern Indian Ocean as the associated showers and thunderstorms continue to move away from land. Radar imagery shows that the associated showers are still producing some moderate rainfall over the open water today as the remnant low pressure area continues to move further away from land.

Two days ago, on January 8, 2012 when Chanda was at tropical storm strength and was just about to make landfall in southern Madagascar, NASA's Terra satellite passed over the storm from space at 07:00 UTC (2 a.m. EST). The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on-board captured a visible image of the storm, showing a rounded and organized shape. Shortly after Chanda made landfall it started weakening and the tropical storm weakened and lost its rounded shape.

Chanda's remnants are expected to continue moving through Southern Indian Ocean and weaken further over the next couple of days. Chanda is not expected to regenerate.

Text Credit: Rob Gutro
NASA's Goddard Space Flight Center, Greenbelt, Md.



Jan. 9, 2012

Over 3 days, AIRS infrared data showed cloud top temperatures growing increasingly colder. › View larger image
Over the days of January 6, 7, and 8, 2012, infrared data from the AIRS instrument on NASA's Aqua satellite showed cloud top temperatures growing increasingly colder (purple is the coldest, greater than -63F).
Credit: NASA JPL, Ed Olsen
TRMM provided a › View larger image
TRMM provided a "top down" analysis of how fast rain was falling throughout Chanda on January 9, 2012 after making landfall. Light to moderate rainfall, depicted in blue and green is falling at a rate between .78 to 1.57 inches (20 to 40 mm) per hour. There were no areas of heavy rain.
Credit: SSAI/NASA, Hal Pierce
TRMM provided a › View larger image
TRMM provided a "top down" analysis of how fast rain was falling throughout Chanda on January 8, 2012. Light to moderate rainfall, depicted in blue and green is falling at a rate between .78 to 1.57 inches (20 to 40 mm) per hour.
Credit: SSAI/NASA, Hal Pierce
Two NASA Satellites See Tropical Storm Chanda in Madagascar

System 99S became a tropical depression in the Southern Indian Ocean over the weekend, and today is a tropical storm named Chanda. NASA's Aqua satellite passed overhead and took Chanda's temperatures with an infrared instrument, and that showed increasingly cold cloud tops. NASA's TRMM satellite measured Chanda's light rainfall from space.

Infrared data can take the temperature of the atmosphere, ocean or land surface, and the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite did just that over several days as Chanda strengthened from a low pressure area to a tropical depression and now a tropical storm. Over the days of January 6, 7, and 8, AIRS data showed cloud top temperatures growing increasingly colder. That indicated that the cloud tops of the thunderstorms that make up the storm were growing higher in the atmosphere, and the uplift, or rising air that forms the thunderstorms, was becoming more powerful over time.

The Tropical Rainfall Measuring Mission (TRMM) satellite has been collecting data that improves understanding of rainfall in the tropics since its launch in 1997. The satellite also provides timely data about the development of tropical cyclones. When Tropical Cyclone Chanda was raining on the coast of Madagascar, TRMM measured its rainfall on January 8, 2012 at 2213 UTC. Data from TRMM's Precipitation Radar (PR) and Microwave Imager (TMI) instruments shows that Chanda was dropping light to moderate rainfall over large areas of southern Madagascar. Deadly tropical cyclones often hit Madagascar but tropical storm Chanda isn't going to one of them. It is predicted to dissipate to a tropical depression it moves further inland.

Chanda was a minimum tropical storm when TRMM passed overhead on January 8, with maximum sustained winds near 35 knots (40 mph) as it moved southeast across the Mozambique Channel.

Chanda is now over land in southwestern Madagascar, and has been bringing rainfall and gusty winds to that area today. At 2100 UTC (4 p.m. EST) on January 9, 2012, Chanda had weakened to a depression with maximum sustained winds near 30 knots (35 mph). It was moving south-southeast at 6 knots (8 mph). Chanda's center was located over land, near 20.5 South and 44.0 East, about 200 nautical miles west-southwest of Antananarivo, Madagascar.

Chanda is expected to continue weakening, and will be watched for regeneration when it moves back into the Southern Indian Ocean.

Text Credit: Rob Gutro/Hal Pierce
NASA's Goddard Space Flight Center/SSAI, Greenbelt, Md.















Jan. 6, 2012

MODIS captured an image of System 99S on January 6 at 1134 UTC (6:34 a.m. EST) › View larger image
NASA's Aqua satellite passed over System 99S on January 6 at 1134 UTC (6:34 a.m. EST) and captured an infrared image of the storm. It showed strong thunderstorms (whitest) building up around the center of circulation. The black area indicates no data.
Credit: NASA/NRL
System 99S Now Better Organized on NASA Satellite Data

The low pressure area near Madagascar now has a high chance of becoming a tropical depression this weekend, as it appeared to be consolidating and organizing on NASA satellite data today.

NASA's Aqua satellite passed over System 99S on January 6 at 1134 UTC (6:34 a.m. EST) and the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument captured an infrared image of the storm. It showed strong thunderstorms building up around the center of circulation. Bands of thunderstorms appear to be building east of the center.

At 1134 UTC, System 99S's maximum sustained winds were near 27 to 32 knots (31 to 37 mph/50 to 60 kmh) - right near tropical depression status (35 mph). The minimum central pressure was 1000 millibars. 99S was centered near 15.2 South latitude and 43.0 East longitude, about 380 miles west-northwest of Antananarivo, Madagascar.

Because wind shear is light and sea surface temperatures are well over the 80F (26.6C) threshold for maintaining a tropical cyclone, 99S stands a good chance to develop.

The Joint Typhoon Warning Center gives this a high chance of developing into a depression this weekend.

Text Credit: Rob Gutro
NASA's Goddard Space Flight Center, Greenbelt, Md.



Jan. 5, 2012

MODIS captured an image of the low called System 99S on January 5, 2012 at 1052 UTC (5:52 a.m. EST). › View larger image
NASA's Aqua satellite captured an image of the low called System 99S on January 5, 2012 at 1052 UTC (5:52 a.m. EST). System 99S is located in the Mozambique Channel, between the island nation of Madagascar and Mozambique on the African continent.
Credit: NASA/NRL
NASA Sees Developing Tropical Disturbance in Southern Indian Ocean

NASA's Aqua satellite imagery has helped forecasters at the Joint Typhoon Warning Center monitor a low pressure area called System 99S in the southern Indian Ocean as it develops.

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Aqua satellite captured an image of the low called System 99S on January 5, 2012 at 1052 UTC (5:52 a.m. EST). System 99S is located in the Mozambique Channel, between the island nation of Madagascar and Mozambique on the African continent. System 99S is centered near 15.2 South latitude and 43.0 East longitude, about 320 nautical miles northwest of Antananarivo, Madagascar. When Aqua passed overhead, System 99S had maximum sustained winds near 20 knots (23 mph/37 kmh) and a minimum central pressure of 1007 millibars.

Today, the city of Ambilobe, located in northwestern Madagascar is reporting thunderstorms from System 99S and that's the forecast over the next couple of days, as System 99S is not expected to move too much. Ambilobe is in the district of the same name, which is a part of Diana Region.

The visible image from Aqua's MODIS instrument revealed that the low pressure area is somewhat elongated. There is a flareup of convection (rising air that condenses and forms the thunderstorms that make up a tropical cyclone) around the center of circulation. There are some signs that bands of thunderstorms may be developing - hinting at a sign of strengthening.

System 99S is battling wind shear as high as 20 knots (23 mph/37 kmh), but it's sitting in waters warm enough to provide energy and enhance convection (if winds cooperate). Sea surface temperatures need to be around 26.6 Celsius (80F), but they are as warm as 30 degrees Celsius (86 F).

Currently, the Joint Typhoon Warning Center gives System 99S a medium chance for developing into a tropical depression in the next day.

Text Credit: Rob Gutro
NASA's Goddard Space Flight Center, Greenbelt, Md.