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Hurricane Season 2011: Tropical Storm Carlos (South Indian Ocean)
02.28.11
 
The MODIS instrument captured this visible image of the storm that showed it had moved away from land. › View larger image
NASA's Aqua satellite flew over a weakening tropical cyclone Carlos on Feb. 24 at 06:15 UTC (1:15 a.m. EST) when it was west of Western Australia. The MODIS instrument captured this visible image of the storm that showed it had moved away from land.
Credit: NASA/Goddard MODIS Rapid Response Team NASA's Aqua Satellite Saw Cyclone Carlos Move Away from Australia and Dissipate

On February 26, the last warning on Tropical Cyclone Carlos was issued as the storm dropped to minimal tropical storm force and was rapidly dissipating. NASA's Aqua satellite captured a visible image of Carlos off the coast of Western Australia as it continued to move away from land.

On February 26, the long life of Tropical Storm Carlos was quickly coming to an end. The Joint Typhoon Warning Center issued their last forecast warning for the storm as it lingered 620 miles west of Perth, Australia near 29.2 South and 104.3 East. It still had maximum sustained winds near 35 knots (40 mph) early that day, but dissipated by Sunday, February 27.

NASA's Aqua satellite flew over a weakening tropical cyclone Carlos on Feb. 24 at 06:15 UTC (1:15 a.m. EST) when it was west of Western Australia. The Moderate Resolution Imaging Spectroradiometer or MODIS instrument captured a visible image of the storm that showed it had moved away from land. No eye was visible in the image, and the storm no longer appeared symmetrical, which is a sign of wind weakening as the storm was being battered by wind shear.

Although born in the Southern Pacific Ocean, Carlos dissipated in the Southern Indian Ocean after crossing over northern Australia in a southwesterly direction.

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


February 23, 2011

TRMM rain falling at a rate of over 2 inches/50 mm per hour (in red) in a small area near Carlos' center › View larger image
NASA's TRMM satellite saw moderate to heavy rainfall, falling at a rate of over 2 inches/50 mm per hour (in red) in a small area near Carlos’ center of circulation on Feb. 22, 2011.
Credit: SSAI/NASA, Hal Pierce Tropical Cyclone Carlos Now Affecting Western Australia

Tropical Cyclone Carlos continues to live and has moved into the Southern Indian Ocean, and is affecting Western Australia.

Tropical Storm Carlos now has maximum sustained winds near 55 knots

On Wednesday, February 23, 2011 it was centered near 22.1S and 114.1E, west of Learmonth, Australia and moving west-southwest near 8 knots (9 mph).

The Tropical Rainfall Measuring Mission (TRMM) satellite passed above tropical cyclone Carlos on February 22 at 1850 UTC (1:50 p.m. EST) as the storm's center was battering coastal Australia. TRMM's rainfall data shows that most of the rainfall with Carlos was located off shore but some bands of moderate rainfall were affecting coastal Australia.

On February 21, when the TRMM satellite passed over tropical cyclone Carlos at 2047 UTC (3:47 p.m. EST), it had tropical storm force wind speeds on the Saffir Simpson scale estimated to be over 50 kts (~58 mph). Carlos has been predicted to batter the Australian coast as it continues traveling southwestward. It is expected to intensify to minimal hurricane force with wind speeds of 65 kts (~75 mph) on February 24 after moving into the open waters of the Indian Ocean.

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


February 18, 2011

infrared image of Tropical Cyclone Carlos › View larger image
This infrared image of remnant low Carlos, taken on Feb. 18 at 0511 UTC from the AIRS instrument on NASA's Aqua satellite shows the bulk of precipitation (blue and purple) hugging the coastline of the Northern Territory. The purple areas indicate the strongest thunderstorms.
Credit: NASA JPL, Ed Olsen Remnants of Cyclone Carlos Continue to Soak Northern Australia on Weekend

The remnant low pressure area formerly known as Tropical Storm Carlos still has a few strong thunderstorms within, as revealed in infrared imagery from NASA today. Carlos' remnants are forecast to continue raining on the northern coastline of Australia's Northern Territory this weekend.

An infrared image of remnant low Carlos, taken on Feb. 18 at 2:41 p.m. Darwin Australia local time (12:11 a.m. EST/0511 UTC) from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite showed the bulk of precipitation hugging the coastline of the Northern Territory. Some spotty areas did have very high thunderstorm cloud tops that were as cold as -52 Celsius (-63 Fahrenheit). Most of those coldest cloud top temperatures (that indicate strongest thunderstorms) were over the Timor Sea at that time. The waters of the Timor Sea are likely contributing to the isolated areas of strong convection in the low pressure area.

At 10 p.m. Darwin Australia local time (7:30 a.m. EST/12:30 UTC) on Feb. 18, the center of the low pressure area was north of Timber Creek and about 100 kilometers southeast of Port Keats. That puts Carlos' center near 14.9 degrees South latitude and 130.1 degrees East longitude. Remnant low Carlos was moving southwest near 8 kmh. It is forecast to continue tracking in a southwesterly direction and move along the southern coast of the Joseph Bonaparte Gulf.

The Australian Bureau of Meteorology still maintains a Cyclone watch for coastal areas from Daly River Mouth in the Northern Territory to Kalumburu in Western Australia, including Port Keats, Kununurra and Wyndham. For the latest radar imagery from the Australian Bureau of Meteorology, go to: http://www.bom.gov.au/products/IDR633.loop.shtml#skip.

Residents along the coastline of Australia's Northern Territory should monitor the progression of Carlos' remnants over the weekend.

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


February 17, 2011

Tropical Storm Carlos in infrared › View larger image
This infrared image of Carlos' cold clouds show that there are still bands of thunderstorms to the north of Carlos' center, picking up energy from the warm waters of the Timor Sea and feeding the storm. The coldest cloud top temperatures appear in purple and are as cold as -63F/-52C.
Credit: NASA/JPL, Ed Olsen NASA Sees Former Tropical Storm Carlos Still a Soaker in the Northern Territory

Now a remnant low pressure area, former Tropical Storm Carlos continues to move southwest inland over Australia's Northern Territory and dump heavy amounts of rainfall. NASA's Aqua satellite saw some of the high thunderstorms within Carlos over land and extending north into the Timor Sea.

The Atmospheric Infrared Sounder (AIRS) instrument onboard NASA's Aqua satellite measures cloud-top, sea surface and land temperatures. Those are important factors in determining the strength and power of a tropical cyclone. Sea surface temperatures need to be at least as warm 26.6 Celsius (80 degrees Fahrenheit) to power a tropical cyclone. Conversely, frigid cloud temperatures, such as those seen in the tops of Carlos' thunderstorms that are as cold as or colder than -52C (-63F) show strong thunderstorms and suggest heavy rainfall.

Even before Carlos became a tropical storm it was a low pressure system that lingered around Darwin, Australia for a couple of days. Over the course of the last four days, Darwin airport reported 26.5 inches of rainfall (673 mm). The largest rainfall total came from Channel Island at 32.87 inches (835 mm).

As Carlos moved south-southwest, those heavy rains continued to fall from those powerful thunderstorms with the cold cloud tops, causing more flooding. The AIRS infrared image from Feb. 17 at 0429 UTC (Feb. 16 at 11:29 p.m. EST) of Carlos' cold clouds showed that there are bands of thunderstorms to the north of Carlos' center. Those bands of thunderstorms are picking up energy from the warm waters of the Timor Sea and feeding the storm, of which the center is over land.

Reports from ABC News Darwin indicated that the Darwin River Dam and the Adelaide River rose significantly. The Territory Wildlife Park in Berry Springs has also reported flooding and their website reported that the park was closed "due to wet weather" because some areas were unsafe for visitors.

At 0900 UTC (4 a.m. EST/ 6:30 p.m. Australia/Darwin local time) on Feb. 17, Carlos had maximum sustained winds near 39 mph. It was located about 75 nautical miles south of Darwin near 13.9 South and 130.6 East. It was moving southwest near 5 knots.

AIRS infrared imagery showed disorganized convection (rising air that forms the thunderstorms that power/make up the tropical cyclone). The low-level circulation is also weakening as it is over land.

Carlos is forecast to continue moving southwest and the Joint Typhoon Warning Center expects Carlos' remnants to move over or south of the Joseph Bonaparte Gulf between 2100 UTC today and 2100 UTC on Feb. 18. As Carlos continues moving southwestward residents in its path should be on guard for moderate to heavy rainfall.

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


February 16, 2011

AIRS infrared image of Carlos and Dianne › View larger image
NASA's Aqua satellite passed over Australia on Feb. 16 at 05:17 UTC (12:17 a.m. EST/ 2:47 p.m. Australia/Darwin local time). The AIRS instrument on Aqua captured an infrared image of Tropical Storm Dianne (left) and Tropical Storm Carlos (right) and found each to have strong convection (purple) with cloudtop temperatures as cold as -52C.
Credit: NASA JPL, Ed Olsen
AIRS visible image of Carlos and Dianne › View larger image
Tropical Storm Dianne (left) is bringing rainfall to Western Australia today and Tropical Storm Carlos (right) is bringing rains and gusty winds to Australia's Northern Territory today.
Credit: NASA JPL, Ed Olsen NASA Sees Tropical Cyclone Double-Trouble for Australia

NASA's Aqua satellite captured an infrared image today of tropical cyclones affecting Australia in the western and northern areas of the country. Newly formed Tropical Storm Carlos is bringing heavy rains and gusty winds to Darwin and the Northern Territory, while Tropical Storm Dianne is bringing rains and winds to Western Australia.

NASA's Aqua satellite passed over Australia today, Feb. 16 at 05:17 UTC (12:17 a.m. EST/ 2:47 p.m. Australia/Darwin local time. The Atmospheric Infrared Sounder (AIRS) instrument captured an infrared image of both tropical storms and found each to have strong convection (rapidly rising air that forms the thunderstorms that power a tropical cyclone). Convection was so strong in Carlos and Dianne that the cloud tops of the thunderstorms within were as cold as or colder than -52 Celsius/ -63 Fahrenheit.

At 0900 UTC (4 a.m. EST/6:30 p.m. Australia/Darwin local time) Tropical Storm Carlos, formerly System 99S, had maximum sustained winds near 35 knots (40 mph/64 kmh) and its center at that time was 15 miles (24 km) south of Darwin, Australia, near 12.7 South and 130.9 East. Eight hours later, by 12 p.m. EST (2:30 a.m. Feb. 17 Australia/Darwin local time), Carlos' center had moved southeast and was inland near Middle Point. Carlos was moving toward the southeast but is expected to turn to the southwest.

Carlos was bringing bands of rainfall to Cape Don, Snake Bay, Cape Fouroroy, and inland over an area that includes Annaburroo, Emerald Springs and Batchelor. For radar from the Australian Bureau of Meteorology, go to: › http://www.bom.gov.au/products/IDR632.loop.shtml.

A Cyclone Warning for Carlos is in effect for coastal areas from Daly River Mouth to Goulburn Island, including Darwin, Croker Island and the Tiwi Islands. A Cyclone Watch continues for coastal areas from Port Keats to Daly River Mouth. The Joint Typhoon Warning Center and Australian Bureau of Meteorology expect Carlos to eventually track southwest over land for the next several days.

Near Western Australia, System 97S intensified into Tropical Storm Dianne overnight. On Feb. 16 at 1500 UTC (10 a.m. EST/12:30 a.m. Feb. 17, Australia/Darwin local time), Tropical Storm Dianne had maximum sustained winds near 40 knots (46 mph / 74 kmh). It was still over open waters in the Southern Indian Ocean, near 18.9 South latitude and 111.3 East longitude, about 250 nautical miles (287 miles/463 km) northwest of Learmonth, Australia.

A Cyclone Watch is currently in effect for coastal areas of Western Australia from Exmouth to Cape Cuvier. During the morning hours (Eastern Time/U.S.) bands of showers were pushing southeast from Dianne from Pardoo (in the east) through Port Hedland southwest to Exmouth. It is currently drifting to the northeast but is expected to loop and move south then southwest after the next day or two.

The Joint Typhoon Warning Center expects Dianne to continue strengthening under an environment of warm sea surface temperatures and low wind shear for the next three days before running into adverse conditions. During that time, however, it is forecast to reach hurricane force and bring gusty winds and heavy rainfall to Learmonth as its center passes to the west.

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


February 15, 2011

The AIRS instrument aboard NASA's Aqua satellite captured an infrared image of System 99S on Feb. 15 › View larger image
The AIRS instrument aboard NASA's Aqua satellite captured an infrared image of System 99S on Feb. 15 at 0441 UTC. The strongest convection (purple) was over the Timor Sea and represented in thunderstorm cloud-top temperatures as cold as or colder than -63 Fahrenheit (-52 Celsius).
Credit: NASA/JPL, Ed Olsen NASA Satellite Catches a Tropical Cyclone Forming Near Darwin, Australia

NASA's Aqua satellite captured a low pressure area known as System 99S that appears to be strengthening very close to Darwin, Australia. Aqua satellite data indicated that the strongest thunderstorms were over the Timor Sea on Feb. 15.

System 99S is a threat to Australia's Northern Territory because on Feb. 15 it was centered only 20 miles (32 km) south of Darwin, Australia, near 12.7 degrees South latitude and 130.7 degrees East longitude. The Joint Typhoon Warning Center gives System 99S a good chance for development in the next 24 hours, and NASA satellite imagery confirms the strong convection and thunderstorms developing in the system.

The Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite captured an infrared image of System 99S on Feb. 15 at 0441 UTC. The infrared image was created at NASA's Jet Propulsion Laboratory in Pasadena, Calif. and showed very strong convection over the Timor Sea (part of the Southern Indian Ocean basin), with the southernmost edge of precipitation near Darwin. That strong convection was represented in thunderstorm cloud-top temperatures as cold as or colder than -63 Fahrenheit (-52 Celsius). Cyclones or hurricanes are made up of hundreds of thunderstorms that circle a low pressure center.

Warnings are now in effect for the Northern Territories, Australia. A Cyclone Warning is in effect for coastal areas from Daly River Mouth to Point Stuart, including Darwin and the Tiwi Islands. In addition, a Cyclone Watch is in effect for coastal areas from Port Keats to Daly River Mouth and Point Stuart to Goulburn Island.

Winds in the area of Darwin are estimated near 25 to 30 knots 29 to 34 mph/36 to 55 kmh). System 99S is meandering northwestward at 1 knot (1 mph/2 kmh). Doppler weather radar at Darwin shows intense convection (thunderstorms) banding along the northern semicircle of the low level circulation center.

The Australian Bureau of Meteorology forecast hints that the low pressure area may continue moving slowly over the next couple of days, as they forecast rain until Friday or Saturday. Windy conditions and heavy rainfall which may produce areas of flooding are in the forecast for Darwin on Wednesday, Feb. 16, and "Flood Threat Advice" and a "Wind Warning" is now in effect.

Forecasters expect System 99S to strengthen as its center drifts over the warm ocean surface. Currently, there is a good chance that System 99S will become a tropical depression or tropical storm.

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