Owen (Southern Pacific Ocean)

December 12, 2018 – NASA Examines Reborn Tropical Cyclone Owen’s Temperatures

An infrared look by NASA’s Aqua satellite found intense storms around the center of the recently revived Tropical Cyclone Owen.

AIRS image of Owen
On Dec. 12 at 0429 UTC, AIRS found cloud top temperatures of strongest thunderstorms in several area around the center. Those temperatures were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 degrees Celsius). They were embedded in a large area where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). Cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain.
Credit: NASA JPL/Heidar Thrastarson

On Dec. 12, Tropical Cyclone Owen was intensifying in Australia’s Gulf of Carpentaria, south of Groote Eylandt. Owen is expected to move slowly overnight and be close to the Northern Territory coast and destructive winds are possible along the coast.

The Australian Bureau of Meteorology or ABM posted warnings and watches. The Warning Zone includes Alyangula in the Northern Territory, to Burketown in Queensland, including Groote Eylandt, Borroloola, Mornington Island. The Watch Zone includes Burketown to Aurukun and adjacent inland areas including Pormpuraaw, Kowanyama and Karumba.

On Dec. 12 at 0429 UTC (Dec. 11 at 11:29 p.m. EST) the Atmospheric Infrared Sounder or AIRS instrument aboard NASA’s Aqua satellite analyzed cloud top temperatures in infrared light. AIRS found cloud top temperatures of strongest thunderstorms in several area around the center. Those temperatures were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 degrees Celsius). They were embedded in a large area where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). Cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain.

At 12:30 a.m. ACST local time on Dec. 13 in Queensland (10 a.m. EST, Dec. 12), Owen had sustained winds near 110 kilometers (68 miles) per hour. It was centered near 15.0 degrees South and 136.4 degrees East. That’s about 105 kilometers (71 miles) south of Groote Eylandt.

On Dec. 12 Tropical Cyclone Owen is located over the southwestern Gulf of Carpentaria and is moving slowly. ABM noted “Owen will continue to move slowly overnight before tracking towards the east, back towards the Queensland coast during Thursday. If Owen tracks more towards the south or west early Thursday morning, it may be located close to the coast between Port Roper and Port McArthur before commencing its eastward track during Thursday. Owen may reach category 3 intensity early Thursday morning. A coastal crossing along the southeast Gulf of Carpentaria coast between Karumba to Pormpuraaw later Friday {Dec. 14] is likely.”

For updated forecasts, visit: http://www.bom.gov.au/

By Rob Gutro
NASA’s Goddard Space Flight Center

Owen (Southern Pacific Ocean)

December 11, 2018 – NASA Measures Rainfall from Tropical Cyclone Owen’s Remnants at Queensland Coast

The low pressure area formerly known as Tropical Cyclone Owen continued to organize and cross the southern Gulf of Carpentaria, Australia on Dec. 11. The Global Precipitation Measurement mission or GPM core satellite provided a look at the rainfall rates within the system.

GPM image of Owen
On December 9, 2018 at 11:31 p.m. AEST (8:31 a.m. EST/1331 UTC). GPM showed rain was falling at a rate of over 32.4 mm (1.3 inches) per hour over northeastern Queensland’s coastline and greater than 52 mm (2 inches) in feeder bands in the Coral Sea off Australia’s coast. This 3-D image showed feeder bands of thunderstorms on the eastern side of tropical cyclone Owen’s remnants contained a few storms that reached heights of 13 km (8.1 miles).Credit: NASA/JAXA, Hal Pierce

On Dec. 11, Australian warnings were posted as Owen continued to consolidate in the Gulf of Carpentaria.  A tropical cyclone watch is in force from Cape Shield Northern Territory to Burketown Queensland, including Mornington Island and Groote Eylandt.

But it was one week before that Tropical cyclone Owen weakened and was downgraded to a tropical low on December 4, 2018.  The tropical low pressure area, also called 05P revived and became a little better organized before it hit the Queensland coast on Dec. 9. Winds in the cyclone had increased to about 35 knots (40 mph) as it moved ashore.  The disturbance is expected to intensify again as it moves westward over the warm waters of the Gulf of Carpentaria. Lower vertical wind shear is also predicted to contribute to a more favorable environment for the low’s intensification into a significant tropical cyclone.


On December 9, 2018 at 11:31 p.m. AEST (8:31 a.m. EST/1331 UTC). GPM showed rain was falling at a rate of over 32.4 mm (1.3 inches) per hour over northeastern Queensland’s coastline and greater than 52 mm (2 inches) in feeder bands in the Coral Sea off Australia’s coast.  This 3-D image showed feeder bands of thunderstorms on the eastern side of tropical cyclone Owen’s remnants contained a few storms that reached heights of 13 km (8.1 miles).Credit: NASA/JAXA, Hal Pierce

The GPM core observatory satellite passed above Tropical Cyclone Owen’s remnants as they approached  Australia’s coast on December 9, 2018 at 11:31 p.m. AEST (8:31 a.m. EST/1331 UTC). GPM’s Microwave Imager (GMI) and GPM’s Dual-Frequency Precipitation Radar (DPR) instruments collected data that showed the intensity of rainfall in the low’s convective storms. GMI indicated that rain was falling at a rate of over 32.4 mm (1.3 inches) per hour over northeastern Queensland’s coastline. GPM’s DPR revealed that rain was falling at a rate of greater than 52 mm (2 inches) in feeder bands in the Coral Sea off Australia’s coast.

A 3-D view was created at NASA’s Goddard Space Flight Center in Greenbelt, Maryland that was derived from GPM’s radar data (DPR Ku Band).  It showed the 3-D structure of precipitation within the remnants of tropical cyclone Owen. A simulated flyby of Owen’s remnants, also created at NASA, showed that feeder bands on the eastern side of tropical cyclone Owen’s remnants contained a few storms that reached heights of 13 km (8.1 miles). GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.

On Dec. 11, Owen was located in the southern part of the Gulf of Carpentaria and tracking to the west-northwest.  The Australian Bureau of Meteorology or ABM noted that Owen was a Category 1 storm with maximum sustained winds near the center of 75 kilometers (46 miles) per hour. That means that Owen has regained its status as a tropical cyclone.  Owen was located near 14.9 degrees south latitude and 138.8 degrees east longitude, about 200 kilometers (124 miles) north-northwest of Mornington Island and 300 kilometers (186 miles) east northeast of Borroloola. Owen was moving to the west-northwest.

Owen is expected to continue moving slowly to the west for a day, then change course to move eastward and back towards the Queensland coast on Thursday Dec. 13. ABM noted that Owen may reach category 3 intensity by Thursday if conditions remain favorable. A coastal crossing along the southeast Gulf of Carpentaria coast during Friday, Dec. 14 is most likely.

For updated forecasts, visit ABM: http://www.bom.gov.au

By Harold F. Pierce / Rob Gutro
NASA Goddard Space Flight Center

Owen (South Pacific Ocean)

December 10, 2018 – NASA-NOAA Satellite Sees Tropical Cyclone Owen’s Remnants Reorganizing

The remnants of Tropical Cyclone have been lingering in the Southern Pacific Ocean for days. On Dec. 10, the storm finally appeared more organized on satellite imagery providing forecasters with a strong indication that it may be reborn as a tropical cyclone. NASA-NOAA’s Suomi NPP satellite passed over the Gulf of Carpentaria and saw the storm.

Suomi NPP image of Owen
On Dec. 10, 2018 the VIIRS instrument aboard NASA-NOAA’s Suomi NPP satellite captured a visible image of the remnants of Tropical Cyclone Owen in the Gulf of Carpentaria, just west of Queensland. Credit: NASA/NRL

On Dec. 10 at 0100 UTC (Dec. 9 at 8 p.m. EST), Owen’s remnants were located near 16.1 degrees south latitude and 144.6 degrees east longitude, approximately 282 nautical miles east-northeast of Mornington Island, Australia, and just west of the northern tip of Queensland.

On Dec. 10 at 0410 UTC (Dec. 9 at 11:10 p.m. EST, the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite analyzed the remnants. VIIRS revealed a consolidating low level circulation center with deep convection building over the center.

The Joint Typhoon Warning Center noted: “Sea surface temperatures in the Gulf of Carpentaria are conducive for future tropical cyclone development. Multiple [computer forecast] models indicate development over the next 24-36 hours with a westward trajectory.”

By Rob Gutro
NASA’s Goddard Space Flight Center

Owen (Southern Pacific Ocean)

December 04, 2018 – NASA-NOAA Satellite Finds Owen Fading in the Coral Sea

Tropical Cyclone Owen appeared disorganized on satellite imagery as it moved through the Coral Sea in the Southern Pacific Ocean. Imagery from the Suomi NPP satellite showed that Owen was being stretched out and had weakened from wind shear.

Suomi NPP image of Owen
On Dec.4, the VIIRS instrument aboard NASA-NOAA’s Suomi NPP satellite captured a visible image of Tropical Storm Owen in the Coral Sea, South Pacific Ocean. Owen was southwest of Vanuatu. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Winds at different levels of the atmosphere pushed against the cylindrical circulation center and skewed it, weakening the rotation. As a result of the wind shear, Owen weakened from a tropical storm to a tropical depression on Dec. 4.

Early on Dec. 4 the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite analyzed Owen, and showed a disorganized storm with little thunderstorm development. The bulk of the clouds and showers were pushed east of the center of circulation from wind shear.

On Dec. 4 at 10 a.m. EDT (1500 UTC) Owen’s maximum sustained winds had dropped to 34.5 mph (30 knots/55.5 kph). It was located approximately 519 nautical miles east of Cairns, Australia. Owen was moving westward.

Although it is a depression, the Joint Typhoon Warning Center noted that there is a chance the storm may re-strengthen after two days when the wind shear is expected to relax. Forecasters are keeping an eye on Owen.

By Rob Gutro
NASA’s Goddard Space Flight Center

Owen (Southern Pacific Ocean)

December 03, 2018 – NASA Catches Newborn Tropical Cyclone Owen’s Rainfall, Observed By GPM Satellite

Tropical Cyclone Owen formed in the Southern Pacific Ocean’s Coral Sea southwest of the Solomon Islands when the GPM core observatory satellite passed above and analyzed its rainfall.

GPM image of Owen
On December 2, 2018 at 9:50 a.m. EST (1450 UTC) the GPM core satellite showed that tropical cyclone Owen was producing heavy downpours. GPM’s GMI indicated that heaviest rainfall was occurring near the low level center of circulation and in feeder bands that were wrapping around Owen’s eastern side. GMI showed that storms in that area were dropping rain at a rate of over 53 mm (2.1 inches) per hour. Credit: NASA/JAXA, Hal Pierce

On December 2, 2018 at 9:50 a.m. EST (1450 UTC) data collected by GPM’s Microwave Imager (GMI) and GPM’s Dual-Frequency Precipitation Radar (DPR) instruments aboard the Global Precipitation Measuring Mission or GPM core satellite showed that tropical cyclone Owen was producing heavy downpours.  GPM’s GMI indicated that heaviest rainfall was occurring near the low level center of circulation and in feeder bands that were wrapping around Owen’s eastern side. GPM’s GMI provided the best coverage of rainfall in the center of the tropical cyclone. GMI showed that storms in that area were dropping rain at a rate of over 53 mm (2.1 inches) per hour. GPM’s radar (DPR Ku Band) probed storms on Owen’s eastern side. DPR indicated that a few of these intense storms, far from Owen’s center, were dropping rain at a rate of over 94 mm (3.7 inches) per hour.


On December 2, 2018 at 9:50 a.m. EST (1450 UTC)  the GPM core satellite showed that tropical cyclone Owen was producing heavy downpours.  GPM’s GMI indicated that heaviest rainfall was occurring near the low level center of circulation and in feeder bands that were wrapping around Owen’s eastern side.  A few powerful storms there were reaching heights above 15 km (9.3km).   GMI showed that storms in that area were dropping rain at a rate of over 53 mm (2.1 inches) per hour. Credit: NASA/JAXA, Hal Pierce

A 3-D animation created with the data showed a simulated flyby above tropical cyclone Owen. GPM’s radar (DPR Ku Band) probes into a feeder band on the eastern side of tropical cyclone Owen showed that a few powerful storms there were reaching heights above 15 km (9.3km).   DPR’s Ku Band radar enables accurate three dimensional measurements of precipitation within a 152 mile (245 km) wide swath. The heights of precipitation over a larger area were estimated by blending measurements from

GPM’s radar (DPR Ku band) with heights based on the Himawari-8 satellite’s infrared temperatures.

On Dec. 3 at 10 a.m. EST (1500 UTC) Tropical cyclone Owen was located near 15.7 degrees south latitude and 155.8 degrees east longitude. That’s 579 miles east of Cairns, Australia. Owen is moving to the east-southeast and has maximum sustained winds 50 knots (57 mph/92.6 kph)

Owen is forecast to move southeast, later west. The storm will strengthen slightly before weakening as it turns west. Owen will dissipate after two days.

By Harold F. Pierce / Rob Gutro
NASA Goddard Space Flight Center

33W (Northwestern Pacific Ocean)

November 29, 2018 – NASA’s IMERG Analyzed Tropical Storm Usagi’s Rainfall

When Tropical Cyclone 33W, also known as Usagi strengthened to hurricane intensity as it approached Vietnam from the South China Sea it dropped a lot of rain. Although the storm weakened to tropical storm intensity when coming ashore in Vietnam, it continued to generate a lot of rain, and NASA added up that heavy rainfall.

GPM data from 33W
NASA rainfall analysis encompassed the period from November 19 to 26, 2018 tracked rain dropped by 33W (Usagi) across the South China Sea into Southeast Asia. Tropical Storm Usagi or 33W often dropped more than 240 mm (9.4 inches) of precipitation over southern Vietnam. Rainfall intensity decreased rapidly as the remnants of Usagi moved inland over Cambodia. Credit: NASA/JAXA, Hal Pierce

Very heavy rainfall and damaging winds accompanied tropical storm Usagi when it hit Vietnam’s southern coast. More than 350 mm (14 inches) of rainfall was reported causing widespread flooding around Ho Chi Minh City.

NASA’s Integrated Multi-satellitE Retrievals for GPM (IMERG) data were used to show estimates of rainfall accumulation produced by Usagi as the tropical cyclone moved across the South China Sea into Southeast Asia. An IMERG accumulation analysis created at NASA’s Goddard Space Flight Center in Greenbelt, Maryland encompassed the period from November 19 to 26, 2018.


NASA rainfall analysis encompassed the period from November 19 to 26, 2018 tracked rain dropped by 33W (Usagi) across the South China Sea into Southeast Asia. Tropical Storm Usagi or 33W often dropped more than 240 mm (9.4 inches) of precipitation over southern Vietnam. Rainfall intensity decreased rapidly as the remnants of Usagi moved inland over Cambodia.  Credit: NASA/JAXA, Hal Pierce

Those data indicated that Usagi dropped moderate to heavy rain along its path. The analysis showed that tropical storm Usagi often dropped more than 240 mm (9.4 inches) of precipitation over southern Vietnam. Rainfall intensity decreased rapidly as the remnants of Usagi moved inland over Cambodia.

GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.

By Harold F. Pierce
NASA Goddard Space Flight Center

Man-yi (Northwestern Pacific Ocean)

November 27, 2018 – NASA-NOAA Satellite Finds Man-yi Becoming Extra-tropical

Tropical Cyclone Man-yi appeared elongated on satellite imagery as it continued moving in a northeasterly direction in the Northwestern Pacific Ocean. Man-yi was being affected by wind shear and was becoming an extra-tropical cyclone.

Suomi NPP image of Man-yi
On Nov. 27, 2018 the VIIRS instrument aboard NASA-NOAA’s Suomi NPP satellite captured a visible image of Tropical Cyclone Man-yi becoming extra-tropical in the Northwestern Pacific Ocean. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

On Nov. 27, the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite analyzed Tropical Cyclone Man-yi. A visible image showed that wind shear was affecting the storm and it was elongated from southwest to northeast.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Winds at different levels of the atmosphere push against the cylindrical circulation center and weaken the storm’s rotation.

On Nov. 27, the Joint Typhoon Warning Center issued the final warning on Man-yi.

At 10 a.m. EDT (1500 UTC) Man-yi’s maximum sustained winds were near 30 knots (34.5 mph/55.5 kph). It was located near 24.1 degrees north latitude and 133.8 degrees east longitude. That’s approximately 351 nautical miles east-southeast of Kadena Air Base, Okinawa, Japan. Man-yi was moving northeastward.

Man-yi already started the process into an extra-tropical transition. That happens when a tropical cyclone has lost its “tropical” characteristics. The National Hurricane Center defines “extra-tropical” as a transition that implies both poleward displacement (meaning it moves toward the north or south pole) of the cyclone and the conversion of the cyclone’s primary energy source from the release of latent heat of condensation to baroclinic (the temperature contrast between warm and cold air masses) processes. It is important to note that cyclones can become extratropical and still retain winds of hurricane or tropical storm force.

On Nov.27, Man-yi is expected to complete extra-tropical transitioning in the next day.

By Rob Gutro
NASA’s Goddard Space Flight Center

Man-yi (Northwestern Pacific Ocean)

November 26, 2018 – NASA’s GPM Shows Small Area of Heavy Rain in Tropical Storm Man-yi

Once a typhoon, Man-yi has weakened to a tropical storm as it continues to track through the Northwestern Pacific Ocean, far to the east of Taiwan. The GPM core satellite provided a look at the rain rates throughout the storm and found heaviest rain displaced to the northeast of the center.

GPM image of Man-yi
NASA-JAXA’s GPM core observatory satellite provided an analyzation of rainfall within Man-yi on Nov. 26 at 11:41 a.m. EST (1641). Heaviest estimated precipitation was falling at a rate of greater than 30 mm (1.2 inches) per hour northeast of the center of circulation. The GPM rainfall was overlaid on an image from Japan’s Himawari-8 satellite. Credit: NASA/NRL/JAXA

The Global Precipitation Measurement mission or GPM core observatory satellite is a joint satellite mission between NASA and the Japan Aerospace Exploration Agency called JAXA. GPM provided an analysis of rainfall within Man-yi on Nov. 26 at 11:41 a.m. EST (1641). Microwave Imager (GMI) instruments revealed heaviest estimated precipitation was falling at a rate of greater than 30 mm (1.2 inches) per hour northeast of the center of circulation.

That heaviest rainfall was displaced from the center because of moderate vertical wind shear pushing it from the center. In general, wind shear is a measure of how the speed and direction of winds change with altitude. Wind shear can tear a tropical cyclone apart or weaken it.

At 10 a.m. EST (1500 UTC) on Nov. 26, Man-yi was a weak tropical storm with maximum sustained winds near 35 knots (40 mph/74 kph). It was centered near 21.4 north latitude and 132.1 east longitude, about 406 nautical miles southeast of Kadena Air Base, Okinawa Island, Japan. Man-yi has tracked north-northwestward.

Man-yi is expected to maintain strength for another day and then be absorbed by the mid-latitude westerlies (winds) and begin extra-tropical transition. Man-yi is expected to be fully transitioned into an extra-tropical cyclone by Nov. 28.

That means that a tropical cyclone has lost its “tropical” characteristics. The National Hurricane Center defines “extra-tropical” as a transition that implies both poleward displacement (meaning it moves toward the north or south pole) of the cyclone and the conversion of the cyclone’s primary energy source from the release of latent heat of condensation to baroclinic (the temperature contrast between warm and cold air masses) processes. It is important to note that cyclones can become extratropical and still retain winds of hurricane or tropical storm force.

By Rob Gutro
NASA’s Goddard Space Flight Center

33W (Northwestern Pacific Ocean)

November 26, 2018 – NASA Sees Tropical Cyclone 33W Dissipating

When NASA-NOAA’s Suomi NPP satellite passed over the Ca Mau Peninsula it captured a visible image of the dissipating former Tropical Cyclone 33W.

Suomi NPP image of 33W
At 2:12 a.m. EDT (0712 UTC) on Nov. 26, the VIIRS instrument aboard NASA-NOAA’s Suomi NPP satellite analyzed Tropical Cyclone 33W’s disorganized remnants dissipating over the Ca Mau Peninsula. Credit: NASA/NRL

The Ca Mau Peninsula is the southernmost area of Vietnam, located between the South China Sea to the east and the Gulf of Thailand on the west.

The Joint Typhoon Warning Center issued its last advisory on 33W known as Usagi, on Sunday, Nov. 25, 2018. On that day, Tropical Storm 33W weakened to a depression after making landfall near Ho Chi Minh City, Vietnam. Maximum sustained winds had weakened to 30 knots (34.5 mph/55.5 kph) and it continued weakening as it moved further inland.

At 2:12 a.m. EDT (0712 UTC) on Nov. 26, the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite analyzed Tropical Cyclone 33W’s disorganized remnants dissipating over the Ca Mau Peninsula.

By Rob Gutro
NASA’s Goddard Space Flight Center

Man-yi (Northwestern Pacific Ocean)

November 23, 2018 – NASA Finds a Cloud-filled Eye in Typhoon Man-yi

Visible imagery from NASA’s Aqua satellite revealed Typhoon Man-yi’s eye had become cloud-filled.

Aqua image of Man-yi
On Nov. 23 the MODIS instrument aboard NASA’s Aqua satellite provided a visible image of Typhoon Man-yi that revealed a cloud-filled eye and a powerful storm. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

On Nov. 23 the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite provided a visible image of Typhoon Many-yi in the Northwestern Pacific Ocean. The MODIS image showed that clouds had filled in over the eye, and the storm had become elongated. The elongation indicates that the storm is being affected by outside winds and will likely weaken.

The Joint Typhoon Warning Center or JTWC noted at 10 a.m. EST (1500 UTC) that Man-yi had maximum sustained winds near 85 knots (98 mph/157 kph). It was centered near 16.9 degrees north latitude and 135.3 degrees east longitude. That’s 729 nautical miles southeast of Kadena Air Base, Okinawa, Japan. Man-yi was moving north-northwest.

JTWC has forecast Man-yi to move northwest and begin weakening. It is expected to make a sharp turn to the northeast. It is expected to pass east of Okinawa Island, Japan.

By Rob Gutro
NASA’s Goddard Space Flight Center