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Tropical Cyclone Gino (Southern Indian Ocean)
02.15.13
 
AIRS image of Gino› Larger image
The AIRS instrument aboard NASA's Aqua satellite captured this infrared image of extra-tropical cyclone Gino on Feb. 15 at 0729 UTC (2:29 a.m. EST). Gino's precipitation was blown southeast of the center by wind shear. The area of strongest thunderstorms (purple) has diminished since Feb. 14. Credit: NASA JPL, Ed Olsen
NASA Sees Extra-tropical Cyclone Gino Fading

NASA's Aqua satellite captured an infrared image of Cyclone Gino as it was transitioning into an extra-tropical cyclone over the open waters of the Southern Indian Ocean.

The latest and final bulletin issued by the Joint Typhoon Warning Center (JTWC) noted that animated multispectral satellite imagery showed that the low-level center is now exposed to outside winds, and the weakening convection had been pushed some 200 nautical miles southeast of the center by wind shear. Satellite data also shows that cold-air stratocumulus clouds moving into the western semi-circle of the low-level center.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite captured an infrared image of extra-tropical cyclone Gino on Feb. 15 at 0729 UTC (2:29 a.m. EST). AIRS imagery confirmed that Gino's precipitation was blown southeast of the center by wind shear and that the area of strong thunderstorms had greatly diminished since Feb. 14.

The final bulletin on Gino placed its center about 1,395 nautical miles south-southeast of Diego Garcia, near 26.4 south latitude and 86.3 east longitude. Gino's maximum sustained winds were down to 40 knots. Extra-tropical storm Gino was moving to the east at 15 knots where it is expected weaken further.

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



February 14, 2013

TRMM image of Gino› Larger image
NASA's TRMM satellite flew over Cyclone Gino on Feb. 14 at 3:06 a.m. EST. The heaviest rain was falling at a rate of 2 inches (red) per hour south of the center, and scattered throughout bands of thunderstorms. Credit: NASA/SSAI, Hal Pierce
NASA Satellite Sees Cyclone Gino's Rainfall Shoved Southward

NASA's Tropical Rainfall Measuring Mission satellite known as TRMM measured Cyclone Gino's rainfall from space and saw the bulk of precipitation was south of the center. Gino's rainfall is being pushed away from the center by vertical wind shear.

TRMM flew over Cyclone Gino on Thursday, Feb. 14 at 0806 UTC (3:06 a.m. EST) and measured the rainfall rates occurring throughout the storm. The bulk of the rainfall stretched from south to southeast of the center. The heaviest rain was falling at a rate of 2 inches (50 mm) per hour southeast of the center, and scattered throughout bands of thunderstorms. The bands of thunderstorms were wrapping from the east quadrant into the southwest quadrant of the storm.

As Gino continues in a southerly direction the vertical wind shear that is already affecting the storm's rainfall is expected to increase, according to the forecasters at the Joint Typhoon Warning Center (JTWC).

At 1500 UTC (10 a.m. EST), Cyclone Gino's maximum sustained winds had dropped to 70 knots (80 mph/129.6 kph). Tropical-storm-force winds extend out 110 nautical miles (126.6 miles/203.7 km) from the center of circulation.

Gino was located near 23.9 south latitude and 80.9 east longitude, about 1,110 nautical miles (1,277 miles/2,056 km) south-southeast of Diego Garcia and far from any land areas. Gino was moving to the south-southeast at 12 knots (13.8 mph/22.2 kph).

JTWC expects Gino to track southeastward along the southwestern edge of a subtropical ridge (elongated area) of high pressure where it will encounter strong vertical wind shear between 40 to 60 knots (46 to 69 mph/74 to lll kph) and sea surface temperatures as cool as 24 Celsius (75.2F). Sea surface temperatures of at least 26.6 C (80F) are needed for a tropical cyclone to maintain intensity. Any temperatures cooler than that, will limit thunderstorm development and weaken the storm.

According to JTWC forecasters, Gino should begin transitioning into an extra-tropical storm where the core of the storm changes from a warm core to a cold core, much like a typical mid-latitude low pressure area. Because of the increasing vertical wind shear and cooler sea surface temperatures, Gino may weaken quickly.

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



February 13, 2013

MODIS image of Gino› Larger image
On Feb. 13 at 0505 UTC (12:05 a.m. EST) the MODIS instrument aboard NASA's Terra satellite captured this visible image of Tropical Cyclone Gino in the Indian Ocean. This close-up image clearly shows the ocean surface in the middle of Gino's eye. Credit: NASA Goddard MODIS Rapid Response Team

AIRS image of Gino› Larger image
The AIRS instrument aboard NASA's Aqua satellite captured this infrared image of Cyclone Gino on Feb. 12 at 1935 UTC (2:35 p.m. EST). Gino still maintained a large area of powerful thunderstorms with cold (purple) cloud top temperatures (-63F/-52C) and a band of strong storms wrapping in from the southeast. Credit: NASA JPL, Ed Olsen
Two NASA Satellites See Cyclone Gino's "Centered" Power

Data from NASA's Aqua and Terra satellites showed powerful thunderstorms continued to wrap around the center of circulation Tropical Cyclone Gino as the storm achieved a category 2 hurricane status.

The Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite captured an infrared image of Cyclone Gino on Feb. 12 at 1935 UTC (2:35 p.m. EST). The AIRS temperature data showed Gino maintained a large area of powerful thunderstorms with cold cloud top temperatures and a band of strong thunderstorms wrapping in from the southeast. Cloud top temperatures in both of those areas were as cold as -63 Fahrenheit (-52 Celsius), and are an indication of heavy rainfall. AIRS data during the early morning hours of Feb. 13 indicated cloud top temperatures have warmed slightly, and convection around Gino's center has weakened a little.

At 0505 UTC (12:05 a.m. EST) on Feb. 13 the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Terra satellite captured a visible image of Gino. The image clearly showed the ocean surface down through the middle of Gino's ragged eye. According to the Joint Typhoon Warning Center, microwave satellite imagery indicated that the eye is weakening on both low- and mid-levels.

By 1200 UTC (7 a.m. EST), Gino's maximum sustained winds were as high as 85 knots (97.8 mph/157.4 kph) making the storm a Category 2 hurricane on the Saffir-Simpson scale. Gino was centered near 20.6 south latitude and 79.9 east longitude, about 875 nautical miles (1,007 miles/ 1,621 km) south-southeast of Diego Garcia, and far from any land areas. Gino was moving to the south-southeast at 11 knots (12.6 mph/20.3 kph).

Gino continues to head into cooler sea surface temperatures. An approaching trough, or elongated area of low pressure is expected to increase wind shear. Those two factors will adversely affect Gino over the next couple of days.

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







February 12, 2013

AIRS image of Gino› Larger image
On Feb. 12 at 0841 UTC, NASA AIRS instrument infrared imagery showed that Cyclone Gino had developed a large area of very cold, high cloud top temperatures (purple) around its center indicating powerful thunderstorms. Credit: NASA JPL, Ed Olsen
NASA Sees Cyclone Gino Wind Up to Wind Down Later

NASA's Aqua satellite passed over Cyclone Gino as the storm continues to wind up in the southern Indian Ocean, consolidating and strengthening. Infrared data shows the storm has strengthened but it is headed for cooler waters which will weaken it in coming days.

On Feb. 12 at 0841 UTC, NASA Atmospheric Infrared Sounder (AIRS) instrument that flies aboard the Aqua satellite captured infrared imagery of Cyclone Gino that showed the storm developed a large area of very cold, high cloud top temperatures around its center indicating powerful thunderstorms. Cloud top temperatures were as cold as -63 Fahrenheit (-52 Celsius) indicating strong storms that have the capability to produce heavy rainfall. The AIRS imagery also suggests a ragged eye had formed.

On Feb. 12 at 1500 UTC (10 a.m. EST), Cyclone Gino's maximum sustained winds had increased to 75 knots (86.3 mph/138.9 kph) making the storm a category one hurricane. Gino was centered near 17.1 south latitude and 79.5 east longitude, about 700 nautical miles (805.5 miles/1,296 km) southeast of Diego Garcia.

Gino has been moving to the south-southwest at 10 knots (11.5 mph/18.5 kph), around the northwestern edge of a subtropical ridge (elongated area) of high pressure.

AIRS data shows that the sea surface temperatures around Gino are currently favorable for further development because they're around a warm 28 degrees Celsius (82.4 Fahrenheit). However, as Gino moves further south-southwest, those sea surface temperatures will drop, making it more difficult for the tropical cyclone to maintain intensity.

In addition, wind shear is expected to increase over the next three days as Gino moves further south. The Joint Typhoon Warning Center expects Gino to transition to a cold core low pressure area by Feb. 15.

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



February 11, 2013

MODIS image of Tropical Cyclone Fifteen› Larger image
On Feb. 11 at 0805 UTC the MODIS instrument aboard NASA's Aqua satellite captured this visible image of Tropical Cyclone Fifteen (15S) in the Indian Ocean. Credit: NASA Goddard MODIS Rapid Response Team
NASA Sees Tropical Cyclone 15S Form in So. Indian Ocean

The fifteenth tropical cyclone of the Southern Indian Ocean season strengthened into a tropical storm today, Feb. 11, and NASA's Aqua satellite passed overhead hours after it reached tropical storm strength.

Tropical Cyclone 15S was born from the low pressure area designated as System 92S. System 92S developed on Feb. 9 and intensified into a tropical storm on Feb. 11 at 0300 UTC. At that time, Tropical Cyclone 15S had maximum sustained winds near 35 knots (40.2 mph/64.8 kph), making it a tropical storm. It was centered near 12.1 south latitude and 82.5 east longitude, about 650 nautical miles (748 miles/1204 km) east-southeast of Diego Garcia. Tropical Cyclone 15S is far from any land areas and is expected to strengthen and dissipate over open ocean.

On Feb. 11 at 0805 UTC the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Aqua satellite captured a visible image of Tropical Cyclone 15S in the Southern Indian Ocean. The image showed that the center of the storm had continued consolidating and was obscured by central dense overcast. Imagery from the special sensor microwave/imager (SSM/I) instrument, a seven-channel, four-frequency passive microwave radiometer system aboard the DMSP satellite showed bands of strong thunderstorms were wrapping into the storm's well-defined center of circulation, an indication that the storm is strengthening.

Tropical Cyclone 15S was moving to the west-southwest at 10 knots (11.5 mph/18.5 kph). The tropical storm is forecast to move to the southwest, then turn south and strengthen to hurricane force within the next two days. The Joint Typhoon Warning Center expects that wind shear and cooler waters will weaken the storm after that time.

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