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Tropical Cyclone Felleng (South Indian Ocean)
02.05.13
 
NPP image of Felleng› Larger image
The night-time satellite image was captured by NASA-NOAA's Suomi NPP satellite on Feb. 3 at 11:20 p.m. local time, Indian/Antananarivo ) when extra-tropical cyclone Felleng was located south of the Mozambique Channel. The bulk of clouds and showers were pushed east and southeast from wind shear. Credit: NASA/NOAA/UWM, William Straka III
NASA-NOAA's Suomi NPP Satellite Sees a Fading Felleng

NASA-NOAA's Suomi National Polar-orbiting Partnership (Suomi NPP) satellite captured a night-time image of extra-tropical cyclone Felleng as it was being battered by wind shear in the Southern Indian Ocean.

The night-time satellite image was captured by the Visible Infrared Imager Radiometer Suite (VIIRS) aboard NASA-NOAA's Suomi NPP satellite on Feb. 3 at 2120 UTC (11:20 p.m. local time, Indian/Antananarivo/1:40 p.m. EST, U.S.) when Felleng was located south of the Mozambique Channel. The VIIRS image was created at the University of Wisconsin-Madison and showed that the bulk of Felleng's clouds and precipitation were pushed east and southeast of the center of circulation as a result of northwesterly vertical wind shear.

On Monday, Feb. 4 at 0600 UTC (1 a.m. EST) the Joint Typhoon Warning Center noted that Felleng completed its extra-tropical transition, and the storm's maximum sustained winds were near 40 knots (46 mph/74 kph). Felleng's center had moved to 31.1 south and 52.8 east, about 605 nautical miles (696.2 miles/1,120 km) south-southwest of La Reunion Island. Felleng continued to move south-southeast in the open waters of the Southern Indian Ocean where it is expected to dissipate in the next couple of days.

The Suomi NPP mission is a bridge between NOAA and NASA legacy Earth observing missions and NOAA's next-generation JPSS. Suomi NPP flies for the first time the groundbreaking new Earth observing instruments that JPSS will use operationally. The first satellite in the JPSS series, JPSS-1, is targeted for launch in 2017. For more information on Suomi NPP, visit: www.nasa.gov/NPP.

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



Feb. 04, 2013

TRMM image of Felleng› Larger image
NASA's TRMM satellite flew over Cyclone Felleng on Feb. 1 at 11:48 a.m. EST and measured a small area of heavy rainfall (red) east of the center of circulation where rainfall was occurring at 2 inches (50 mm per hour). Most of the other precipitation was moderate, falling at a rate of 1.18 to 1.5 inches (30 to 40 mm) per hour. Credit: NASA/SSAI, Hal Pierce
NASA Sees the Falling of Cyclone Felleng

Cyclone Felleng traveled through the Mozambique Channel during the week of Jan. 28, 2013 and emerged south into the Southern Indian Ocean where it transitioned into a cold core low pressure area. NASA's TRMM satellite captured a look at the rainfall rates occurring in Felleng as it was making that transition on Feb. 1.

NASA's Tropical Rainfall Measuring Mission (TRMM) satellite flew over Cyclone Felleng on Feb. 1 at 1648 UTC (11:48 a.m. EST) as it was exiting the Mozambique Channel and becoming extra-tropical. TRMM measured a small area of heavy rainfall east of the center of circulation where rainfall was occurring at 2 inches (50 mm per hour). Most of the precipitation wrapped from northeast to south to west of the center and was moderate, falling at a rate of 1.18 to 1.5 inches (30 to 40 mm) per hour. The northwestern quadrant had very little rainfall at the time of the TRMM overpass.

The Joint Typhoon Warning Center (JTWC) , the organization that forecasts tropical cyclones in the Southern Indian Ocean, issued their final advisory on Cyclone Felleng on Feb. 3 at 2100 UTC (4 p.m. EST). At that time, Felleng's maximum sustained winds were near 40 knots (46 mph/74 kph. Felleng was located about 745 nautical miles (857 miles/1,380 km) south of La Reunion Island, near 33.4 South and 54.3 East. Felleng was moving to the south-southeast at 15 knots (17.2 mph/27.7 kph).

By Monday, Feb. 4 at 0600 UTC Felleng had completed its extra-tropical transition, and the storm's maximum sustained winds continued near 40 knots (46 mph/74 kph). Felleng's center had moved to 31.1 south and 52.8 east, about 605 nautical miles (696.2 miles/1,120 km) south-southwest of La Reunion Island. Felleng continues to move south-southeast in the open waters of the Southern Indian Ocean where it is expected to dissipate in the next couple of days.

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



Jan. 31, 2013

AIRS image of Felleng› Larger image
This series of infrared images of Cyclone Felleng was taken over 5 days by the AIRS instrument that flies aboard NASA's Aqua satellite. It shows the storm's growth into a cyclone and its weakening back to a tropical storm. The purple areas are the coldest cloud top temperatures, and strongest storms with heaviest rainfall occurring in the cyclone. Top row L to R: Jan. 28 at 2153 UTC; Jan. 29 at 10:11 UTC; Jan. 30 at 2147 UTC. Bottom row, L to R: Jan.31 at 0959 UTC and Feb. 1 at 1041 UTC. Credit: NASA JPL, Ed Olsen

MODIS image of Felleng› Larger image
The MODIS instrument aboard NASA's Terra satellite captured this visible image of Tropical Cyclone Felleng off the east coast of Madagascar on Feb. 1 at 0620 UTC (1:20 a.m. EST). Credit: NASA Goddard MODIS Rapid Response Team
NASA Captures Five Days of Cyclone Felleng

NASA's Aqua satellite captured infrared imagery of Cyclone Felleng's ups and downs over the last five days. Today, Feb. 1, Felleng continues to weaken and move through the Mozambique Channel.

The Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite continually provides infrared imagery of tropical cyclones, land and sea surface temperatures to forecasters. The Joint Typhoon Warning Center is the organization that forecasts tropical cyclones in the Southern Indian Ocean and has been utilizing the AIRS data.

A five day series of AIRS imagery from Jan. 28 to Feb. 1 shows the intensification of Cyclone Felleng. AIRS imagery was captured on Jan. 28 at 2153 UTC; Jan. 29 at 1011 UTC; Jan. 30 at 2147 UTC, Jan.31 at 0959 UTC and Feb. 1 at 1041 UTC.

On Jan. 29, as Felleng was approaching peak intensity the eye became apparent on AIRS imagery. Felleng peaked on Jan. 30 with maximum sustained winds near 115 knots (132.3 mph/213 kph), and when NASA's Aqua satellite passed overhead at 2147 UTC (4:47 p.m. EST), the winds had dropped and the eye was no longer visible on the AIRS imagery.

Another instrument aboard NASA's Terra satellite provided a spectacular visible image of Felleng after it weakened back to tropical storm strength. The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra satellite captured an image of Felleng on Feb. 1 at 0620 UTC (1:20 a.m. EST). In the image, Felleng's eye was no longer visible and the storm appeared to be elongated. Eastern outer bands of thunderstorms were still over both La Reunion and Mauritius Islands, while Felleng's center remained over the open waters of the Mozambique Channel. Most of the cloud cover and associated rainfall was falling over open water.

On Feb. 1 at 0900 UTC, Felleng's maximum sustained winds were near 60 knots (69 mph/111 kph) and weakening. Felleng was near 21.3 south and 50.7 east, about 275 nautical miles (316.5 miles/ 509.3 km) west of La Reunion Island. It was moving to the south-southeast at 6 knots (7 mph/11 kph) and generating 26-foot-high (7.9 meter-high) seas in the Mozambique Channel.

La Reunion continued its Yellow Alert on Feb. 1. For updates (in French), visit: http://www.meteo.fr/temps/domtom/La_Reunion/meteoreunion2/#

Forecasters at the Joint Typhoon Warning Center (JTWC) expect Felleng to continue moving south-southeast and weaken as vertical wind shear increases. The JTWC takes Felleng out of the Mozambique Channel and into the open waters of the Southern Indian Ocean over the next several days where it is expected to become extra-tropical and dissipate.

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



Jan. 31, 2013

MODIS image of Felleng› Larger image
On Jan. 31, NASA's Aqua satellite captured an image of Cyclone Felleng at 5:05 a.m. EST on Jan. 31 that showed strong thunderstorms continue to wrap around the center of circulation, and Felleng's eye is now obscured by high clouds. The western edge of the storm is brushing eastern Madagascar (left) and eastern edge is over La Reunion and Mauritius islands (right). Credit: NASA Goddard MODIS Rapid Response Team
NASA Sees Cyclone Felling Squeeze Between Madagascar and La Reunion

NASA satellite imagery saw Cyclone Felleng appear to squeeze between Madagascar and La Reunion island as it moves southward in the Mozambique Channel.

On Jan. 31 at 5:05 a.m. EST, The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA's Aqua satellite captured an image of Cyclone Felleng that showed thunderstorms continue to wrap around the center of circulation. The image also showed that Felleng's eye is now obscured by high clouds. The MODIS image showed that the western edge of the storm was brushing eastern Madagascar and eastern edge was over both La Reunion and Mauritius islands. Infrared satellite imagery revealed that strongest convection has been decreasing throughout the cyclone during the early morning hours of Jan. 31. Although unseen on visible satellite data, microwave imagery showed an eye feature with the deep convection confined to the eastern semi-circle.

On Jan. 31 at 1500 UTC (10 a.m. EST) Tropical Cyclone Felling was moving through the Mozambique Channel. Felleng had maximum sustained winds near 85 knots (97.8/157.4 kph). Tropical-storm-force winds extend out 140 miles (161 miles/259 km) from the center. It was centered near 18.2 south latitude and 51.1 east longitude, about 300 nautical miles (345 miles/555 km) west-northwest of LaReunion Island. Felleng is moving to the southwest at 6 knots (7 mph/11 kph). La Reunion refers to Felleng as "07/20122013." Felleng is creating very rough seas in the northern Mozambique Channel with wave heights up to 32 feet (9.7 meters).

La Reunion Island has issued a Yellow alert as Felleng continues its trek through the channel. The Yellow alert means that residents can expect strong winds, heavy rains and high swells.

The Joint Typhoon Warning Center expects Felleng to continue weakening as it moves in a southeasterly direction.

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



Jan. 30, 2013

NPP image of Felleng› Larger image
NPP IMAGE: NASA-NOAA's Suomi NPP satellite captured this false-colored night-time image of Cyclone Felleng during the night on Jan. 29, at 2109 UTC. The image clearly shows bands of thunderstorms wrapping into the eye of the storm. Felleng is west of northern Madagascar. Credit: William Straka, UWM/NASA/NOAA
NASA-NOAA's Suomi NPP Satellite Sees Powerful Cyclone Felleng

False-colored night-time satellite imagery from NASA-NOAA's Suomi NPP satellite clearly shows bands of thunderstorms wrapping into the eye of Cyclone Felleng as it parallels the coast of eastern Madagascar.

The Visible Infrared Imager Radiometer Suite (VIIRS) aboard NASA-NOAA's Suomi NPP satellite captured a night-time image of Cyclone Felleng when it was located east of Madagascar (4:09 p.m. EST/Jan. 30 at 12:09 a.m. local time, Madagascar). The image was created at the University of Wisconsin-Madison and was false colored to reveal temperatures. The image shows powerful thunderstorms wrapping into the 20 nautical mile-wide (23 miles / 37 km) eye of the storm.

Felleng has intensified since Jan. 29 and as of 1500 UTC (10 a.m. EST) on Jan. 30, had maximum sustained winds near 115 knots (132.3 mph/213 kph). Felling is centered near 16.2 south and 52.6 east, about 400 nautical miles (460.3 miles/741 km) north-northwest of La Reunion Island. Felleng is moving to the southwest at 13 knots (15 mph/24 kph) and is a threat to both Madagascar and La Reunion. The storm is creating dangerous seas, with wave heights up to 38 feet (11.5 meters).

La Reunion has already issued a Yellow Alert. For updates (in French), visit: http://www.meteo.fr/temps/domtom/La_Reunion/meteoreunion2/#

Felleng is turning towards the south and continues to intensify. The Joint Typhoon Warning Center expects Felleng to pass between La Reunion and Madagascar.

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



Jan. 29, 2013

MODIS image of Felleng› Larger image
On Jan. 29, NASA's Aqua satellite captured an image of Cyclone Felleng at 5:14 a.m. EST that showed strong thunderstorms around the center of circulation and a 22 nautical mile-wide eye obscured by high clouds. The western edge of the storm is approaching Madagascar (left). Credit: NASA Goddard MODIS Rapid Response Team

NPP image of Felleng› Larger image
NASA-NOAA's Suomi NPP satellite captured this false-colored night-time image of Cyclone Felleng during the night on Jan. 28, 2013. Felleng is northwest of Madagascar. The image revealed some pretty cold overshooting tops, topping at ~170K. The image shows some interesting gravity waves propagating out from the storm in both the thermal and visible imagery. Credit: William Straka, UWM/NASA/NOAA
NASA Sees Some Powerful "Overshooting Cloud Tops" in Cyclone Felleng

NASA satellite imagery revealed that Cyclone Felleng is packing some powerful thunderstorms with overshooting cloud tops.

An overshooting (cloud) top is a dome-like protrusion that shoots out of the top of the anvil of a thunderstorm and into the stratosphere. It takes a lot of energy and uplift in a storm to create an overshooting top, because usually vertical cloud growth stops at the tropopause and clouds spread horizontally, forming an "anvil" shape on top of the thunderstorms.

During the night-time hours (Madagascar local time) of Jan. 28, NASA-NOAA's Suomi NPP satellite captured a night-time image of Cyclone Felleng when it was located northwest of Madagascar. The image was created at the University of Wisconsin-Madison and was false colored to reveal temperatures. The image showed some pretty cold overshooting cloud tops, topping at ~170K (-153.7F/ -103.1C). The image also showed some interesting gravity waves (waves in the atmosphere) propagating out from the storm in both the thermal (infrared) and visible imagery. The infrared imagery also showed that Felleng has strengthened significantly since the previous day as convective bands of thunderstorms are wrapping more tightly into the eye.

On Jan. 29, the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard NASA's Aqua satellite captured an image of Cyclone Felleng at 1015 UTC (5:14 a.m. EST) that showed strong thunderstorms around the center of circulation and a 22 nautical mile-wide-eye (25.3 mile/40.7 km) obscured by high clouds. The image clearly showed the western edge of the storm is approaching Madagascar.

Cyclone Felleng has continued to intensify, as NASA-NOAA's Suomi NPP image indicated with the identification of overshooting cloud tops. On Jan. 29 at 1500 UTC (10 a.m. EST), Felleng has maximum sustained winds near 90 knots (103.6 mph/166.7 kph). Felleng was located near 14.3 south latitude and 54.6 east longitude, about 420 nautical miles (483.3 miles/777.8 km) north of La Reunion. Felleng is moving west-southwestward at 8 knots (9.2 mph/14.8 kph).

On Jan. 30, a trough (elongated area) of low pressure is expected to turn Felleng southward. The storm is expected to continue intensifying as it moves parallel to the eastern coast of Madagascar.

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



Jan. 28, 2013

AIRS image of Felleng› Larger image
NASA's Aqua satellite passed over Tropical Storm Felleng on Jan. 28 at 4:29 a.m. EST and showed very cold cloud top temperatures (purple) and bands of thunderstorms wrapping around the center. Credit: NASA JPL, Ed Olsen
NASA Satellites Analyze New Tropical Storm Felleng

NASA's Aqua and Terra satellites have provided infrared imagery of Tropical Storm Felleng to forecasters. The imagery helped forecasters determine that Felleng would continue to intensify as it nears Madagascar.

Another tropical cyclone was born in the Southern Indian Ocean on Saturday, Jan. 26 as Tropical Storm 13S came together. On Sunday, Jan. 27 at 10 a.m. EST/U.S. (1500 UTC), Tropical Storm 13S was located at 13.7 South and 61.9 East, about 590 nautical miles (679 miles/1,093 km) northeast of La Reunion Island. Tropical Storm 13S was moving to the west-southwest at 11 knots (12.6 mph/20.3 kph). At that time, the low-level circulation center was partially exposed to outside winds. The strongest convection and heaviest rainfall was being pushed to the north of the center from southerly wind shear.

The MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard NASA's Terra satellite captured an infrared image of Tropical Storm 13S on Jan. 27 at 1814 UTC (1:14 p.m. EST) that showed some strong thunderstorms around the center of circulation.

On Jan. 28, Tropical Storm 13S was renamed "Felleng." La Reunion Island has also assigned "07/20132013" to the storm because it will be affected by Felleng on its track to the west.

NASA's Aqua satellite passed over Tropical Storm Felleng on Jan. 28 at 0929 UTC (4:29 a.m. EST) and the Atmospheric Infrared Sounder (AIRS) instrument captured an image of the storm's cloud top temperatures. AIRS observes in infrared light, which basically provides temperature information. In respect to tropical cyclones, the higher the thunderstorms (they're made up of hundreds of thunderstorms), the colder the clouds, and the stronger the thunderstorms. AIRS data showed that cloud top temperatures around the center of Felleng were as cold as -63 Fahrenheit (-52 Celsius). Those strong storms are indicative of areas where heavy rain is falling.

AIRS imagery also showed that bands of thunderstorms were wrapped tightly around Felleng's center indicating that the storm was well-organized. AIRS data also showed that the storm is symmetrical. A non-symmetrical storm usually weakens, while symmetrical storms have the potential to strengthen.

On Jan. 28 at 1500 UTC (10 a.m. EST), Felleng had maximum sustained winds near 45 knots (51.7 mph/83.3 kph). Tropical-storm-force winds extend about 60 nautical miles (69 miles/111 km) from the center. Felleng was located near 13.3 south latitude and 58.4 east longitude, about 500 nautical miles (576 miles/926 km) north-northeast of La Reunion Island. Felleng is moving to the west at 10 knots (11.5 mph/18.5 kph).

The Joint Typhoon Warning Center expects Tropical Storm Felleng to intensify over the next several days as it moves west. Felleng is expected to reach hurricane (cyclone) strength as it approaches Madagascar's east coast, and then it is forecast to be pushed south by an approaching area of low pressure. Felleng is forecast to move south and travel between eastern Madagascar and La Reunion Island by Feb. 1.

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