Jan. 23, 2009
Three NASA Satellite Instruments Capture Fanele's Extratropical Transition
Hurricane Season 2009: Fanele (Indian Ocean)
Fanele left its mark on Madagascar and is now in the open waters of the southern Indian Ocean, where it will continue to weaken over the weekend of Jan. 24-25, 2009. Three instruments on two NASA satellites captured Fanele's transition into an extratropical storm.
A conversion to "extratropical" status means that the area of low pressure (known as Fanele in this case) eventually loses its warm core and becomes a cold-core system. During the time it is becoming extratropical the cyclone's primary energy source changes from the release of latent heat from condensation (from thunderstorms near the storm's center) to baroclinic (temperature and air pressure) processes. When a cyclone becomes extratropical it will usually connect with nearby fronts and or troughs (extended areas of low pressure) consistent with a baroclinic (pressure) system. When that happens it appears the system grows larger while the core weakens.
NASA's MODIS Instrument's Visual Image Shows Weakening
This visible image from the Moderate Imaging Spectroradiometer, or MODIS instrument that flies onboard NASA's Terra satellite, shows the lack of circulation in Fanele which indicates a weakening storm. MODIS captured this image on Jan.23 at 6:12 Zulu Time (1:12 a.m. EST). At that time, Fanele still had maximum sustained winds near 35 knots (40 mph) and had a minimum central pressure of 996 millibars. It was located near 29.4 degrees south latitude, and 54.0 degrees east longitude.
NASA's AMSR-E Instrument Sees Rainfall, Sea Temperatures and More
Four hours later, at 10:31 Zulu Time (5:31 a.m. EST), NASA's Aqua satellite passed over Fanele and captured an image of the storm with the Advanced Microwave Scanning Radiometer-E (AMSR-E) instrument onboard. In those four hours, Fanele had weakened considerably. Fanele's maximum sustained winds had dropped to 25 knots (28 mph), and the storm's pressure had risen to 1004 millibars, another indicator of a weakening tropical cyclone. At 10:31 Zulu time, Fanele had moved to 30.9 degrees south latitude and 53.2 degrees east longitude.
Data from AMSR-E provides measurements of precipitation rate, cloud water, water vapor, sea surface winds, and sea surface temperature, all of which are indicators in whether a tropical cyclone is strengthening or weakening. One unique aspect of AMSR-E sea surface temperature data is that it reads those surface temperatures through most types of cloud cover, supplementing infrared-based measurements that are restricted to cloud-free areas.
NASA's AIRS Instrument Sees Fanele's Cold Clouds
A second instrument on NASA's Aqua satellite captured Fanele at the same time as the AMSR-E instrument. The Atmospheric Infrared Sounder (AIRS) instrument on Aqua captured both storm's cloud temperatures. AIRS produced this infrared image on Jan. 23 at 5:29 a.m. EST (10:29 UTC). In this image, it's obvious that the circular shape associated with tropical cyclones isn't there, and Fanele's high, cold clouds more closely resemble a comma shape.
The AIRS infrared image shows those frigid cloud top temperatures that forecasters a clue to a storm's strength. The coldest temperatures (and highest cloud tops) are usually shown in purple. Those purple areas are as cold as 220 degrees Kelvin or minus 63 degrees Fahrenheit (F) or colder. The lower clouds are depicted as blue areas, which are around 240 degrees Kelvin, or minus 27F.
Because extratropical storm Fanele is no longer a threat to land, the Joint Typhoon Warning Center stopped issuing advisories on the system on Jan. 22 at 21:00 UTC (4:00 p.m. EST). At that time, Fanele was further north and west of its present location. Specifically, it was at 27.9 degrees south, and 51.8 degrees east or 370 miles south-southeast of Antananarivo, Madagascar. During the time of the last advisory, Fanele still had sustained winds of 45 knots (51 mph), which are now down to 25 knots (28 mph).
Fanele is expected to continue to fade in the southern Indian Ocean over the weekend.
Rob Gutro, NASA's Goddard Space Flight Center
Jan. 22, 2009 - 2nd update
Tropical Storm Fanelle Moving Into Open Waters
On January 22, Tropical Storm Fanelle was now pushing into the open waters of the Indian Ocean.
This black and white image of Fanelle was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite on January 22, 2009, at 06:00 UTC (1:00 a.m. Eastern Standard Time).
At this time, Fanelle had winds of 30 knots (34 mph) and had a minimum central pressure of 1000 millibars. It was located near 25.0 degrees south latitude and 48.7 degrees east longitude and it was moving away from Madagascar.
Rob Gutro/Goddard Space Flight Center
Jan. 22, 2009
Tropical Storm Fanele Re-Emerges into Waters, Leaves Devastation Behind
Now a tropical storm in the Mozambique Channel, Fanele's trek through western Madagascar caused a lot of damage as it plowed through the country as a category one hurricane with 90 mph winds.
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.
According to Reuters news service, 2,600 people are now homeless and as many as 4,000 people have been affected by Fanele's winds and rains. Reports cite widespread flooding and extensive structural damages. Reuters reports that 80 percent of the homes in the town of Morondava are now roof-less. Power and water supplies are currently in the process of being restored. The Associated press reported that about 9,400 people were isolated in one district near Morondava where half the land area was underwater.
On Thursday, January 22 at 09:00 UTC (4:00 a.m. EST), Fanele had weakened into a weak tropical storm with maximum sustained winds near 30 knots (35 mph). It was located near 25.0 degrees south latitude and 48.7 degrees east longitude, that's about 370 miles south-southeast of Antananarivo, Madagascar. Fanele was moving east-southeast near 16 knots (18 mph). Forecasters at the Joint Typhoon Warning Center expect that Fanele will briefly re-intensify before starting to transition to extra-tropical status.
NASA's Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite captured this visible image of Fanele on Jan. 19 at 10:59 UTC (5:59 UTC), just before it made landfall. Fanele is now southeast of where it was at that time.
NASA's Tropical Rainfall Measuring Mission (TRMM) satellite was also flying overhead on Jan. 19 before Fanele made landfall, and it captured a snapshot of the heavy rains that the storm brought southwestern Madagascar.
This image was created from data on Jan. 19 at 19:34 UTC (4:34 p.m. EST). This TRMM image shows the horizontal pattern of rain intensity within Fanele. The center is located near the yellow, green and red areas, which indicate rainfall between 20 and 40 millimeters (.78 to 1.57 inches) per hour. The very tiny red areas are considered moderate rainfall. TRMM is a joint mission between NASA and the Japanese space agency JAXA.
Madagascar usually experiences as many as four major cyclones annually. Last year, 2008, more than 100 deaths were attributed to cyclones Fame, Ivan and Jokwe.
> Historic information on Tropical Cyclone Fame
Historic information on Tropical Cyclone Ivan
> Historic information on Tropical Cyclone Jokwe
> TRMM Web site
Rob Gutro, NASA's Goddard Space Flight Center
Jan. 21, 2009
Two Tropical Cyclones Hit Madagascar
Two tropical cyclones spawned this week in the southern Indian Ocean: Eric and Fanele, and both brought rains and winds to the African island nation of Madagascar. Although Eric was short-lived and has moved off-shore and weakened, Fanele continues to rain over the island.
Madagascar is an island nation in the Indian Ocean. It’s the fourth largest island in the world, and is located off the southeastern coast of Africa.
Tropical Cyclone Eric
On Monday, Jan. 19, Tropical cyclone Eric, also known as Tropical Cyclone 08S (for the eighth tropical cyclone in the southern Indian Ocean this season) made landfall in the eastern Fenerive-Est region, packing sustained winds around 62 mph (100km/hour). By Jan. 20, Eric was a tropical depression. By Jan. 21, Eric was extratropical and was located more than 300 miles west-southwest of the island of Reunion. Reunion is located east of Madagascar, and about 130 miles (200 km) southwest of Mauritius, the nearest island. Because Eric is fading quickly, the Joint Typhoon Warning Center will not issue any additional advisories on the system.
NASA's Aqua satellite flew over both Eric and Fanele and generated images of them from space. The Atmospheric Infrared Sounder (AIRS) instrument onboard Aqua captured both storms' cloud temperatures. AIRS produced this infrared image of Eric on Jan. 20 at 4:59 a.m. EST (9:59 UTC). Eric is seen as the circular area of blue, located east of Madagascar.
The AIRS infrared images show the frigid cloud top temperatures, giving forecasters a clue to a storm's strength. The coldest temperatures (and highest cloud tops) are usually shown in purple. Those purple areas are as cold as 220 degrees Kelvin or minus 63 degrees Fahrenheit (F) or colder. The lower clouds are depicted as the blue areas, which are around 240 degrees Kelvin, or minus 27F.
Tropical Storm Fanele Still a Category One Hurricane Over Land
While Eric came from the west and hit Madagascar, Fanele came from the east.
On Jan. 20, while Fanele was still over open water, it had intensified strongly and was a category three tropical cyclone. The storm then headed southeast into Madagascar and made landfall on the morning of Jan. 21, local time, with maximum sustained winds of 115 mph (190 km/hr).
Once Fanele made landfall, it began moving across the island, and was quickly losing intensity. Although the storm will reemerge over water in one or two days' time, it will not regain strength due to hostile atmospheric conditions east of Madagascar. Fanele is forecast to become extratropical within 48 hours.
Aqua's AIRS instrument produced these infrared images of Fanele on Jan. 20 at 22:29 UTC (7:29 p.m. EST) and Jan. 21 at 5:41 a.m. EST (10:41 UTC). The remnant of extratropical storm Eric can be seen to the southeast in the right image from January 21.
At 9:00 UTC (4:00 a.m. EST) on Jan. 21, Fanele was located near 21.2 degrees south latitude and 44.2 degrees east longitude. That's about 260 miles west-southwest of Antananarivo, Madagascar. Its maximum sustained winds had decreased to 75 knots (86 mph), making it a category one hurricane on the Saffir-Simpson scale.
Rob Gutro, NASA's Goddard Space Flight Center