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Hurricane Season 2009: Izilda (Western Indian Ocean)
March 30, 2009

Tropical Cyclone Izilda Dissipates

satellite image of Izilda Credit: NASA/JPL
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Tropical Cyclone Izilda reached a Category Two on the Saffir-Simpson hurricane scale, made a brief landfall in western Madagascar and dissipated along the west coast of the island nation, according to the Mozambican National Meteorological Institute.

Reuters news wire reported that Izilda's landfall occurred in southwestern Madagascar on March 26 at 12:00 UTC (8 a.m. EDT). It made landfall as a tropical storm with sustained winds near 63 mph (101 kilometers/hour). The approximate coordinates of landfall are 24.0 degrees south latitude and 42.8 degrees east longitude.

The final warning on Izilda was issued on March 26 at 21:00 UTC (5 p.m. EDT) when it had sustained winds near 35 knots (40 mph). The sustained winds dropped by 23 mph, nine hours after it made landfall. During the time of the last advisory, it was located 350 miles southwest of Antananarivo, Madagascar. Izilda weakened quickly because of wind shear (winds blowing at different levels of the atmosphere that tear a storm apart).

NASA's Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured this visible image of Tropical Storm Izilda on Mar. 27 at 22:23 UTC (6:23 p.m. EDT). Izilda's clouds and rains are seen in the blue and purple areas located west and northern areas of Madagascar.

The infrared image clearly shows a large temperature difference between Izilda's cloud-tops and the warm ocean temperatures of the Mozambique Channel. In this image, the orange temperatures are 80F (300 degrees Kelvin) or warmer. Izilda's lowest temperatures (in purple) are associated with high, cold cloud tops. Those temperatures are as cold as or colder than 220 degrees Kelvin or minus 63 degrees Fahrenheit (F). The blue areas are around 240 degrees Kelvin, or minus 27F.

Madagascar has experienced a number of tropical cyclones this season, and forecasters are continuing to keep a close eye on that region.

Credit: Rob Gutro, NASA's Goddard Space Flight Center

March 27, 2009

TRMM image of Izilda> Click for larger image
Credit: Hal Pierce(SSAI/NASA GSFC)
Tropical Cyclone Izilda Near Madagascar

On March 26, 2009 at the TRMM satellite flew above tropical cyclone Izilda when it was was near the southwest coast of Madagascar. Izilda briefly had hurricane force winds of about 65 knots (~ 75 miles per hour) but had weakened to tropical storm strength with winds of about 55 knots (~ 63 miles per hour) at the time of the TRMM pass shown above. Izilda is expected to continue weakening and drift slowly westward. The center of Izilda's surface circulation is clearly shown by TRMM's Visible (VIRS) image to be separated to the west of the storm's middle and upper level circulation. The overlaid precipitation analysis from TRMM's Microwave Imager (TMI) instrument shows that the heaviest rainfall (~ 20-30 millimeters per hour) is located east of Izilda's center of circulation and just off the southwest tip of Madagascar.

Text credit: Hal Pierce(SSAI/NASA GSFC)

March 26, 2009

MODIS image of Izilda> Click for larger image
Credit: NASA image by Jeff Schmaltz, MODIS Rapid Response Team, Goddard Space Flight Center
Cyclone Izilda had estimated winds of 65 kilometers per hour (40 miles per hour or 35 knots) at roughly the same time that the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this image on March 25, 2009. The storm intensified the following day, and the Joint Typhoon Warning estimated that Izilda had sustained winds of 101 kilometers per hour (63 miles per hour or 55 knots) and gusts up to 130 kilometers per hour (81 miles per hour or 70 knots) on March 26.

Most of the clouds in this photo-like image from March 25 are concentrated in Cyclone Izilda, leaving a relatively clear view of southern Madagascar. A line of dark green mountains runs up the eastern side of the island. To the east, the land is lush and green. Inland, to the west of the mountains, the land is drier and brown.

The high-resolution image provided above is at MODIS’ full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

Text credit: Holli Riebeek

Izilda off the coast of Madagascar Credit: NASA JPL, Ed Olsen
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March 25, 2009

Another New Cyclone Near Madagascar: Izilda

Tropical Storm Izilda has formed in the Mozambique Channel, and forecasters are closely watching the storm's track, because it could move westward to mainland Africa or south into the open waters of the Indian Ocean.

The Mozambique Channel is a part of the Indian Ocean located between the island of Madagascar and Mozambique, located in the southeastern region of the African continent.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured this visible image of Izilda on Mar. 24 at 10:53 UTC (6:53 a.m. EDT) as the satellite flew overhead. In the image, Madagascar is visible to the right of the storm.

"The Madagascar Magnet has been turned on again," said Ed Olsen, Earth scientists and a senior member of the technical staff of the Atmospheric Infrared Sounder instrument, at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

On March 25 at 06:00 UTC (2:00 a.m. EDT), Izilda was located about 365 nautical miles southwest of Antananarivo, Madagascar, near 23.1 south latitude and 42.2 east longitude. It has slowed down and tracked south-southeastward at 3 knots (3 mph). Izilda currently has sustained winds near 35 knots (40 mph).

Forecasters are watching a ridge of high pressure building to the south of the storm, which, depending on the position of the high will either steer the storm to the west, or to the south.

Text credit: Rob Gutro, NASA's Goddard Space Flight Center