Ambali – Southern Indian Ocean

Dec. 05, 2019 – NASA Finds Tropical Cyclone Ambali Rapidly Intensifying

NASA’s Terra satellite captured an image of Tropical Cyclone Ambali and the visible image showed that the storm was rapidly intensifying.

Terra image of Ambali
On Dec. 5 2019, the MODIS instrument that flies aboard NASA’s Terra satellite provided a visible image of Tropical cyclone Ambali in the Southern Indian Ocean and showed powerful storms around the center of circulation and a large band of thunderstorms feeding into the center from the west. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

Ambali formed as a tropical depression in the Southern Indian Ocean on Dec. 4 and quickly strengthened into a tropical storm. Today, Dec. 5, it has reached what is considered hurricane status in the Atlantic and Northeast Pacific.

On Dec. 5, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Terra satellite provided a visible image of Ambali. The MODIS image showed powerful thunderstorms circling the center of circulation. Meanwhile microwave satellite imagery shows tight banding of thunderstorms around the center of circulation and the development of an eye.

The shape of the storm is a clue to forecasters that a storm is either strengthening or weakening. If a storm takes on a more rounded shape it is getting more organized and strengthening. Conversely, if it becomes less rounded or elongated, it is a sign the storm is weakening. Ambali appeared more circular than it did 24 hours before, indicating it was strengthening and consolidating.

On Dec. 5 at 10 a.m. EST (1500 UTC), Tropical Cyclone Ambali was located near latitude 9.2 degrees south and longitude 62.7 degrees east, about 595 miles west-southwest of Diego Garcia. Ambali is moving west-southwest and has maximum sustained winds 70 knots (81 mph/130 kph).

Ambali will move south-southwest as it rapidly intensifes. Ambali is expected to peak at 100 knots (115 mph/185 kph) later today before running into hostile atmospheric conditions leading to dissipation in four days.

NASA’s Terra satellite is one in a fleet of NASA satellites that provide data for hurricane research.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

02S – Southern Indian Ocean

Dec. 05, 2019 – NASA Finds Tropical Cyclone 02S Consolidating

NASA’s Aqua satellite captured an image of Tropical cyclone 02S and the visible image showed that the storm was becoming better organized.

Aqua image of 02S
On Dec. 5 2019, the MODIS instrument that flies aboard NASA’s Aqua satellite provided a visible image of Tropical Cyclone 02S in the Southern Indian Ocean and showed powerful storms around the center of circulation and a large band of thunderstorms feeding into the center from the west. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

Tropical Cyclone 02A formed as a tropical depression in the Southern Indian Ocean on Dec. 4 and strengthened into a tropical storm.

On Dec. 5, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite provided a visible image of 02S. The MODIS image showed powerful thunderstorms circling the center of circulation and a large, thick band of thunderstorms feeding into the center from the west.

The shape of the storm is a clue to forecasters that a storm is either strengthening or weakening. If a storm takes on a more rounded shape it is getting more organized and strengthening. Conversely, if it becomes less rounded or elongated, it is a sign the storm is weakening. 02S appeared more circular than it did 24 hours before, indicating it was strengthening and consolidating.

On Dec. 5 at 4 a.m. EST (0900 UTC), Tropical Cyclone 02S was located near latitude 6.7 degrees south and longitude 50.9 degrees east, about 867 miles north-northwest of St Denis, La Reunion Island. 02S is moving west-southwest and has maximum sustained winds 40 knots (46 mph/74 kph).

Tropical Cyclone 02S is forecast to turn to the south-southwest. The storm is forecast to make landfall in northwestern Madagascar after five days.

NASA’s Aqua satellite is one in a fleet of NASA satellites that provide data for hurricane research.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

Pawan (was 06A) – Northern Indian Ocean

Dec. 05, 2019 – NASA Tracking Tropical Storm 06A Through Arabian Sea

NASA-NOAA’s Suomi NPP satellite passed over the Arabian Sea and captured a visible image of Tropical Storm 06A, now renamed Tropical Storm Pawan.

Suomi NPP image of 06A
NASA-NOAA’s Suomi NPP satellite passed over Tropical Storm Pawan or 06A on Dec. 5, 2019 as it was moving through the western Arabian Sea, spreading clouds as far northwest as Oman and Yemen on its way toward Somalia. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

Visible imagery from NASA satellites help forecasters understand if a storm is organizing or weakening. The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of 06A on Dec. 5.  VIIRS showed Tropical Storm Pawan or 06A was moving through the western Arabian Sea, spreading clouds as far northwest as Oman and Yemen on its way toward Somalia. Satellite imagery has shown limited deep convection and development of strong thunderstorms over the partially exposed low-level circulation center.

On Dec. 5, at 4 a.m. EST (0900 UTC), Tropical Cyclone Pawan (06A) was located near latitude 9.5 degrees north and longitude 55.9 degrees east, about 462 miles south-southeast of Salalah, Oman. The storm was moving to the west and had maximum sustained winds 40 knots (45 mph/74 kph). The storm is expected to weaken over the next day as it approaches Somalia.

Tropical Cyclone Pawan (06A) is in the process of turning west-southwest and is expected to make landfall in Somalia by Dec. 7.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro 
NASA’s Goddard Space Flight Center

Kammuri – Northwestern Pacific Ocean

Dec. 05, 2019 – NASA Analyzes Kammuri’s Heavy Rainfall    

NASA provided analyses of Typhoon Kammuri’s heavy rainfall on its track through the Northwestern Pacific Ocean using the Global Precipitation Measurement mission or GPM core satellite.

GPM instrument image of rainfall rates in Kammuri
Instantaneous surface rain rates (mm/hr) associated with Typhoon Kammuri derived from the Dual-polarization Radar onboard the GPM core satellite at 18:27 UTC 29 November 2019 (3:27 am Palau Time, PWT, 30 November) when the storm was moving westward through the central Philippine Sea. GPM showed areas of moderate to heavy rain (shown in yellow, orange and red, respectively) organized into loose bands rotating around the northern and western side of the storm.   Image from NASA GSFC using GPM data archived at https://pps.gsfc.nasa.gov/.

While the Atlantic hurricane season officially ended on November 30, Typhoon Kammuri (known as Tisoy in the Philippines), which recently struck the central Philippines as a powerful Category 4 typhoon, is a reminder that the Pacific typhoon season is not yet over.  In fact, while typhoon season does peak from around June through November, similar to the Atlantic, typhoons can occur throughout the year in the Pacific.

History of Kammuri

Kammuri first formed into a tropical depression from an area of low pressure on the 25th of November north of Micronesia in the west central Pacific about 500 miles southeast of Guam.  Kammuri intensified slowly and was still a tropical storm when the center passed about 130 miles south of Guam on the evening of Dec. 26.   As the storm made its way through the eastern and central Philippine Sea over the next few days it was kept in check at times by moderate wind shear and hovered around typhoon intensity.

GPM IMERG data of rainfall accumulations in Kammuri
Typhoon Kammuri’s surface rainfall accumulations estimated from the NASA IMERG  from  Nov. 24 at 7 p.m. EST to Dec 3 at 10 p.m. EST.  Heaviest rains were over the central Philippine Sea where the cyclone stalled. Those were well over 500 mm (~20 inches, in red).  Most of the central Philippines, including southern Luzon, received up to 150 mm or more (over 6 inches, light blue areas) with the highest amounts over the northern half of the island of Samar where rainfall totals ranged from 250 to 350 mm (~10 to 14 inches, shown in yellow and light orange).  Credit: NASA GSFC using IMERG data/with the Giovanni online data system, developed and maintained by the NASA GES DISC.

Analyzing Kammuri’s Rainfall from Space

During this period, the GPM core satellite overflew the storm.  The first image was taken at on Nov. 29, 2019 at 1:27 p.m. EST (18:27 UTC/Nov. 30, 2019 at 3:27 a.m. local Palau Time, PWT) and shows surface rain rates within Kammuri from the GPM Dual-polarization Radar (DPR) when the storm was about 800 miles east of the Philippines.  At the time, Kammuri was a Category 1 typhoon with sustained winds estimated at 85 mph by the Joint Typhoon Warning Center (JTWC).

GPM, a satellite managed by both NASA and the Japan Aerospace Exploration Agency, showed areas of moderate to heavy rain organized into loose bands rotating around the northern and western side of the storm.  The eye, which is located along the right side of the image, was identifiable by the curvature in the inner rain bands, but the eyewall itself appeared rather weak.  These features are consistent with Kammuri having a well-developed though not yet powerful circulation. That would change over the next few days as Kammuri began to approach the Philippines.

Initially, Kammuri weakened slightly after the time of the GPM overpass, but then on the evening of December 1 (local time), the storm began a rapid deepening cycle and intensified from a Category 1 typhoon with sustained winds estimated at 80 mph by JTWC at 12:00 UTC (7 a.m. EST/9:00 pm PWT) on the Dec. 1 to a Category 4 storm with sustained winds of 130 mph just 24 hours later.  It was at this time that Kammuri made its first landfall in the Philippines around 11:00 p.m. local time near Gubat in the Bicol region in the Province of Sorsogon along the southeastern tip of Luzon.

As it continued on westward through the central Philippines, Kammuri weakened, crossing the island of Mindoro as a Category 2 storm before exiting the Philippines into the eastern South China Sea.

IMERG Finds Heavy Rains in the Philippines

In addition to its powerful winds, Kammuri brought heavy rains to the Philippines.  IMERG, the Integrated Multi-satellitE Retrievals for GPM, is a unified satellite precipitation product produced by NASA to estimate surface precipitation over most of the globe.  IMERG is managed at NASA’s Goddard Space Flight Center in Greenbelt, Md.

With IMERG, precipitation estimates from the GPM core satellite are used to calibrate precipitation estimates from microwave and infrared sensors on other satellites to produce half-hourly precipitation maps at 0.1o horizontal resolution.

IMERG surface rainfall accumulations for the period from Nov. 25 through Dec. 3 for the Philippines and the surrounding region from the time when Kammuri first became a tropical depression southeast of Guam until it had passed over Mindoro and into the South China Sea.  The heaviest rains associated with Kammuri by far are off shore, especially over the central Philippine Sea where the cyclone stalled for a period producing rainfall totals well over 500 mm (~20 inches).

Over land, most of the central Philippines, including southern Luzon, received on the order of 150 mm or more (over 6 inches) with the highest amounts over the northern half of the island of Samar where rainfall totals are on the order of 250 to 350 mm (~10 to 14 inches).

So far, Kammuri is being blamed for up to 17 fatalities in the Philippines.  After leaving the Philippines, Kammuri weakened significantly and is expected to weaken even further and dissipate as the cyclone is sheared apart and driven southward by the northeast monsoon.

Kammuri’s Status on Dec. 5

On Dec. 5 at 4 a.m. EST (0900 UTC), Tropical Storm Kammuri was in the South China Sea and was dealing with adverse atmospheric conditions, which were weakening the storm. It  was centered near latitude 13.8 degrees north and longitude 113.7 degrees east, about 340 nautical  miles east-southeast of Da Nang, Vietnam. Kammuri was moving to the southwest and had maximum sustained winds near 35 knots (40 mph/65 kph), making it a Category 1 tropical storm.

Kammuri continues to weaken and is expected to dissipate soon.

By Steve Lang
NASA’s Goddard Space Flight Center

Kammuri – Northwestern Pacific Ocean

Dec. 04, 2019 – Suomi NPP Satellite Finds Kammuri Weakening in South China Sea

NASA-NOAA’s Suomi NPP satellite passed over the South China Sea and provided forecasters with a visible image of Tropical Storm Kammuri on Dec. 4.

Suomi NPP image of Kammuri
NASA-NOAA’s Suomi NPP satellite provided two visible images of Kammuri on Dec. 4 that were combined at NASA’s Goddard Space Flight Center in Greenbelt, Md. to show the entire storm. The combined VIIRS image showed that Kammuri’s center of circulation was almost in the center of the South China Sea, while a tail of clouds streamed over Luzon, the northern Philippines and north to Taiwan. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided two visible images of Kammuri on Dec. 4 that were combined at NASA’s Goddard Space Flight Center in Greenbelt, Md. to show the entire storm. NASA Worldview, Earth Observing System Data and Information System (EOSDIS) provided the image. The combined VIIRS image showed that Kammuri’s center of circulation was almost in the center of the South China Sea, while a tail of clouds streamed over Luzon, the northern Philippines and north to Taiwan.

Visible imagery from NASA satellites helps forecasters understand if a storm is organizing or weakening by the storm’s shape. NASA-NOAA’s Suomi NPP satellite showed that the storm appears to be elongating, indicating it is weakening.

On Dec. 4 at 10 a.m. EST (1500 UTC), Kammuri’s maximum sustained winds were near 40 knots (46 mph/74 kph) and weakening. Tropical Storm Kammuri (Philippines designation Tisoy) was centered near latitude 14.4 degrees north and longitude 115.7 degrees east. That is about 285 nautical miles west of Manila, Philippines. Kammuri has moved far enough away from the Philippines that all warnings have been dropped.

Kammuri is weakening as it moves west through the South China Sea. The Joint Typhoon Warning Center forecasts Kammuri to turn south-southwest and dissipate by December 6.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro 
NASA’s Goddard Space Flight Center

06A – Northern Indian Ocean

Dec. 04, 2019 – NASA Sees Tropical Storm 06A Maintaining Strength

NASA’s Aqua satellite found some powerful storms in Tropical Storm 06A as it moved through the Arabian Sea toward Somalia.

Aqua image of 06A
On Dec. 4 at 4:55 a.m. EST (0955 UTC), the MODIS instrument aboard NASA’s Aqua satellite gathered temperature information about Tropical Storm 06A’s cloud tops. MODIS found several small areas of powerful thunderstorms (yellow) where temperatures were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 degrees Celsius), embedded in a much larger area of slightly warmer cloud tops (red) of minus 70 degrees Fahrenheit (minus 56.6 Celsius). Credit: NASA/NRL

NASA’s Aqua satellite used infrared light to analyze the strength of storms in 06A and found it was maintaining strength. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On Dec. 4 at 4:55 a.m. EST (0955 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite gathered temperature information about Tropical Storm 06A’s cloud tops. MODIS found several small areas of powerful thunderstorms where temperatures were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 degrees Celsius), embedded in a much larger area of slightly warmer cloud tops of minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.

On Dec. 4 at 10 a.m., EST (1500 UTC), Tropical Storm 06A was located near latitude 8.4 degrees north and longitude 57.0 degrees east in the Arabian Sea, Northern Indian Ocean. That is about 864 nautical miles east-southeast of Djibouti. Djibouti is a sovereign state in the Horn of Africa with a coastline on the Gulf of Aden. It is bordered by Somalia to the south, Ethiopia to the west, and Etriea to the north. 06A was moving to the northwest and had maximum sustained winds near 35 knots (40 mph/65 kph).

The Joint Typhoon Warning Center or JTWC noted, “The storm’s good outflow (air that flows outwards from a storm system) and warm sea surface temperatures are being offset by strong (20-25 knots/23-29 mph/37-46 kph) vertical wind shear to make the environment marginally supportive. Tropical Storm 06A appeared to accelerate west-northwestward over the past six hours, suggesting a subtropical ridge (an elongated area of high pressure) to the north has become the primary steering mechanism.” Over the next 24 hours, the subtropical ridge will cause 06A to turn onto a west southwestward track and remain there until making landfall and dissipating.

Tropical Storm 06A is expected to make landfall in east central Somalia late on Dec. 6.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

07A – Northern Indian Ocean

Dec. 04, 2019 – NASA Finds Wind Shear Battering Tropical Cyclone 07A

NASA’s Aqua satellite found that wind shear was tearing at Tropical Storm 07A in the Arabian Sea.

Aqua image of 07A
On Dec. 4 at 3:20 a.m. EST (0820 UTC), the MODIS instrument aboard NASA’s Aqua satellite gathered temperature information about Tropical Storm 07A’s cloud tops. MODIS found three small areas of powerful thunderstorms (red) where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). MODIS also showed westerly wind shear was pushing the bulk of clouds east of the storm’s center. Credit: NASA/NRL

NASA’s Aqua satellite used infrared light to analyze the strength of storms in 07A. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures. On Dec. 4 at 3:20 a.m. EST (0820 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite gathered temperature information about Tropical Storm 07A’s cloud tops. MODIS found three small areas of powerful thunderstorms where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.

Cloud tops surrounding those small areas were warmer, indicating those storms were weaker. The bulk of thunderstorms in 07A were warmer than minus 70 degrees Fahrenheit and they were being pushed to the east from westerly wind shear.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels. Winds from the west were displacing the bulk of clouds and showers from 07A and pushing them to the east.

On Dec. 4 at 4 a.m., EST (0900 UTC), Tropical Storm 07A was located near latitude 14.9 degrees north and longitude 68.7 degrees east in the Arabian Sea, Northern Indian Ocean. That is about 616 nautical miles south of Karachi, Pakistan. 07A was moving to the northwest and had maximum sustained winds near 45 knots.

Tropical Storm 07A is expected to weaken to a depression by Dec. 5 and then dissipate.

Typhoons and hurricanes are the most powerful weather event on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

07A – Northern Indian Ocean

Dec. 03, 2019 – NASA Finds Second Tropical System Develops in Arabian Sea

Tropical Storm 07A has developed in the eastern Arabian Sea, one day after Tropical Storm 06A developed in the western part of the sea. Infrared imagery from an instrument aboard Terra revealed that very high, powerful storms with very cold cloud top temperatures were southwest of the center.

Terra image of 07A
On Dec. 3 at 12 pm. EST (1700 UTC) the MODIS instrument that flies aboard NASA’s Terra satellite showed the southeastern quadrant of newly formed Tropical Storm 07A where cloud top temperatures (in yellow) were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius). Credit: NASA/NRL

Tropical Storm 07A developed on Dec. 2 from a low-pressure area designated as System 91A. The storm consolidated into a tropical storm today and was renamed 07A.

Tropical cyclones are made of up hundreds of thunderstorms, and infrared data can show where the strongest storms are located. They can do with infrared data that provides temperature information.  The strongest thunderstorms that reach highest into the atmosphere have the coldest cloud top temperatures.

On Dec. 3 at 12 pm. EST (1700 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Terra satellite showed the southeastern quadrant of newly formed Tropical Storm 07A where cloud top temperatures (in yellow) were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius). NASA research has found that cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.

On Dec. 3 at 10 a.m. EDT (1500 UTC), Tropical Storm 07A had maximum sustained winds near 35 knots (40 mph /65 kph). It was located near latitude 13.4 degrees north and longitude 70.2 degrees east, about 367 nautical miles south-southwest of Mumbai, India.

Forecasters at the Joint Typhoon Warning Center expect 07A will move northwest. The system is not expected to intensify and is expected to dissipate in a day or so.

Tropical cyclones are the most powerful weather event on Earth. NASA researches these storms to determine how they rapidly intensify, develop and behave. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA’s Goddard Space Flight Center

Kammuri – Northwestern Pacific Ocean

Dec. 03, 2019 – NASA Catches Typhoon Kammuri Post Landfall

NASA-NOAA’s Suomi NPP or S-NPP satellite provided infrared and night-time imagery of Typhoon Kammuri shortly after it made landfall in the Philippines.

Suomi NPP infrared image of Kammuri
NASA-NOAA’s S-NPP satellite provided an infrared image of Typhoon Kammuri on Dec. 2 at 12:07 p.m. EST (1707 UTC) that showed the eye near Gubat, Sorsogon, the southeastern part of Luzon. A wide, thick band of powerful thunderstorms (red) circled the entire eye, where cloud top temperatures were as cold as or colder than 210 Kelvin (minus 81.6 degrees Fahrenheit/minus 63.1 degrees Celsius). NASA research has shown that cloud top temperatures that cold or colder have the ability to generate heavy rainfall. The strongest storms were west and southwest of center where cloud tops were as cold (black) as 119 Kelvin (minus 117.6 degrees Fahrenheit/minus 83.1 degrees Celsius). Credit: NOAA/NASA/UWM-CIMSS-SSEC/William Straka III

On Dec 2 at 7 a.m. EST (1200 UTC) Kammuri, known as Tisoy in the Philippines, had maximum sustained winds near 115 knots (132 mph), and that made it a Category 4 hurricane on the Saffir Simpson Hurricane Wind Scale.

Per the 10 a.m. EST (1500 UTC) bulletin from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), at 11 p.m. PHT, Philippine  Standard Time. Kammuri (Tisoy) made landfall near Gubat, Sorsogon which is located in the extreme southeastern part of Luzon, Philippines

Views of a Typhoon from NASA Satellites

NASA-NOAA’s Suomi NPP or S-NPP satellite saw Typhoon Kammuri on Dec. 2 at 12:07 p.m. EST (1707 UTC). Infrared and nighttime images were created by William Straka III, Researcher at the University of Wisconsin – Madison, Space Science and Engineering Center (SSEC), Cooperative Institute for Meteorological Satellite Studies (CIMSS). The infrared image showed the eye of Kammuri (Tisoy) near Gubat, Sorsogon, in the southeastern part of Luzon. A thick,wide band of powerful thunderstorms circled the entire eye, where cloud top temperatures were as cold as or colder than 210 Kelvin (minus 81.6 degrees Fahrenheit/minus 63.1 degrees Celsius). NASA research has shown that cloud top temperatures that cold or colder have the ability to generate heavy rainfall.

Straka noted that several prominent features include tropospheric gravity waves along with multiple overshooting cloud tops. In addition, there were also some mesospheric gravity waves. Infrared data revealed coldest temperatures of cloud tops were as cold as 119 Kelvin (minus 117.6 degrees Fahrenheit/minus 83.1 degrees Celsius) in the western and southwestern quadrants of the storm. Those were the most powerful storms that likely produced the highest rainfall rates.

Suomi NPP nighttime image of Kammuri
NASA-NOAA’s S-NPP satellite provided an infrared image of Typhoon Kammuri on Dec. 2 at 12:07 p.m. EST (1707 UTC) that showed the eye near Gubat, Sorsogon, in southeastern part of Luzon. City lights could be seen to the north and south of the storm, in Northern Luzon, Western and Central Visayas regions, and Northern Mindanao. The eastern Visayas and Bicol regions were covered by Kammuri’s clouds. Credit: NOAA/NASA/UWM-CIMSS-SSEC/William Straka III

In the nighttime image from the S-NPP satellite, Kammuri’s eye was visible near Gubat, Sorsogon, in southeastern Luzon. City lights could be seen to the north and south of the storm, in Northern Luzon, Western and Central Visayas regions, and Northern Mindanao. The eastern Visayas and Bicol regions were covered by Kammuri’s clouds.

On Dec. 2 at 12:11 a.m. EST (0511 UTC), the Atmospheric Infrared Sounder or AIRS instrument aboard NASA’s Aqua satellite provided a look at the cloud top temperatures in Typhoon Kammuri. A thick, wide band of powerful thunderstorms (red) circled the entire eye, where cloud top temperatures were as cold as or colder than 210 Kelvin (minus 81.6 degrees Fahrenheit/minus 63.1 degrees Celsius), which confirmed the Suomi NPP satellite data.

AIRS image of Kammuri
On Dec. 2 at 12:11 a.m. EST (0511 UTC), the Atmospheric Infrared Sounder or AIRS instrument aboard NASA’s Aqua satellite provided a look at the cloud top temperatures in Typhoon Kammuri. A thick, wide band of powerful thunderstorms (red) circled the entire eye, where cloud top temperatures were as cold as or colder than 210 Kelvin (minus 81.6 degrees Fahrenheit/minus 63.1 degrees Celsius), which confirmed the Suomi NPP satellite data. Credit: NASA JPL/Heidar Thrastarson

Warnings in Effect on Dec. 3, 2019

PAGASA continues to track Kammuri in order to assess the impacts on the various islands in the path of the storm.  On Dec. 3, PAGASA maintained the following warnings.

Tropical Cyclone Wind Signal number 3 was in effect for Luzon: Northern Occidental Mindoro, Lubang Island.

Tropical Cyclone Wind Signal number 2 was in effect for Luzon: Oriental Mindoro, Batangas, rest of Occidental Mindoro, Marinduque, Cavite, Laguna, Rizal, Bataan, Metro Manila, southern Bulacan, southern Pampanga, southern Zambales, Calamian Islands, and western parts of Quezon.

Tropical Cyclone Wind Signal number 1 was in effect for Luzon: Northern parts of Camarines Sur, southern Neuva Ecija, southern Aurora, northern parts of Palawan, Cuyo Islands, rest of Quezon, rest of Camaines Sur, rest of Zambales, rest of Pampanga and rest of Bulacan. In addition, Signal 1 was in effect for Visayas: Northern Aklan and northern Antique.

Status of Kammuri (Tisoy) on Dec. 3

On Dec. 3, 2019 at 10 a.m. EST (1500 UTC) Typhoon Kammuri (Tisoy) was located near latitude 13.2 degrees north, and longitude 120.1 degrees east,  about 99 nautical miles south-southwest of Manila, Philippines.  Kammuri is moving west and had maximum sustained winds of 80 knots (92 mph/148 kph). 

Typhoon Kammuri continues to weaken as it emerges on the western edges of the Philippine archipelago. The storm is forecast to turn to the east-northeast and is expected to quickly turn to the south-southwest and dissipate.

For updated forecasts from PAGASA, visit: www.pagasa.dost.gov.ph

By Rob Gutro
NASA’s Goddard Space Flight Center

06A – Northern Indian Ocean

Dec. 03, 2019 – NASA-NOAA Satellite Finds Development of Tropical Cyclone 06A

Imagery from NASA-NOAA’s Suomi NPP satellite showed that a tropical depression in the Arabian Sea has consolidated and organized despite facing wind shear. Tropical Depression 06A is now Tropical Cyclone 06A.

Suomi NPP image of Tropical Cyclone 06A
NASA-NOAA’s Suomi NPP satellite passed over Tropical Cyclone 06A in the Arabian Sea on Dec. 3 and a visible image of 06A that revealed powerful storms were northwest of the center of circulation. The center of circulation is apparent in the VIIRS image as a small area of circulation located southeast of the bulk of clouds and showers. Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS)

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of 06A that revealed powerful storms were northwest of the center of circulation, but the storm was able to strengthen despite the harsh environmental conditions. The center of circulation is apparent in the VIIRS image as a small area of circulation located southeast of the bulk of clouds and showers.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels. In the case of Tropical Cyclone 06A, southeasterly winds are pushing the bulk of the storm’s clouds to the northwest.

The Joint Typhoon Warning Center or JTWC in Pearl Harbor, Hawaii noted, “A fully exposed low level circulation center in animated multispectral satellite imagery. Strong (20-30 knot/ 23 to 34.5 mph /32 to 55.5 kph) vertical wind shear is offsetting good poleward outflow and warm (28 to 29 degrees Celsius/82.4 to 84.2 degrees Fahrenheit) sea surface temperature, hampering intensification.” Tropical cyclones require sea surface temperatures of at least 26.6 degrees Celsius (80 degrees Fahrenheit) to maintain strength or intensify, so the warmer sea surface temperatures are allowing 06A to maintain its strength.

JTWC noted that at 10 a.m. EST (1500 UTC) on Dec. 3, that 06A had maximum sustained winds near 35 knots (40 mph/65 kph). 06A was located near latitude 7.1 degrees north and longitude 57.4 degrees east. It was about 784 nautical miles east-northeast of Mogadishu, Somalia.

It is moving to the northeast, however, and the track will slowly turn west southwestward as a subtropical ridge (elongated area of high pressure) builds back in to the north.

Tropical Cyclone 06A is forecast to make landfall in east central Somalia on Dec. 6 as a tropical storm.

Tropical cyclones and hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro 
NASA’s Goddard Space Flight Center