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Hurricane Season 2011: Tropical Depression Tokage (Western No. Pacific Ocean)
07.15.11
 
This image combines TRMM rainfall data with visible imagery from the MTSAT-2. › View larger image
This image combines TRMM rainfall data with visible imagery from the MTSAT-2. The orange area shows rainfall at a rate of 1 inch per hour.
Credit: NASA/JTWC/NRL
NASA Sees Birth Tropical Depression Tokage Fighting Typhoon Ma-on

The ninth tropical depression of the western North Pacific hurricane season has been born and NASA satellite data shows that the heaviest rainfall is falling at about 1 inch per hour. Satellite data also shows that Tokage is in an "atmospheric battle" with nearby Typhoon Ma-on.

The Tropical Rainfall Measuring Mission (TRMM) satellite captured an image of the some of the rainfall occurring in the newborn tropical depression on July 15 at 0606 UTC (2:06 a.m. EDT). The rainfall is displaced about 50 nautical miles to the west-southwest from the center of Tokage's circulation. That's an indication that wind shear is taking a toll on the newborn storm and pushing those showers and thunderstorms away from the storm's center. Further, satellite imagery shows that the low-level circulation center is also fully exposed to outside winds.

At 1500 UTC (11 a.m. EDT) on July 15, Tropical Depression Tokage had maximum sustained winds near 25 knots (29 mph/46 kmh). Tokage is moving east and away from the Philippines at 11 knots (13 mph/20 kmh). It was located about 395 nautical miles north of Palau. Palau is an island nation in the western North Pacific Ocean. It is located about 500 miles (800 km) east of the Philippines.

Tokage is currently fighting with Typhoon Ma-on, also in the vicinity. Outflow winds from Typhoon Ma-on are preventing convection and thunderstorms from developing in Tokage, even though Tokage is in warm sea surface temperatures.

The forecasters at the Joint Typhoon Warning Center think that Tokage is going to be short-lived and knocked out by Ma-on. As Tokage continues tracking north-northeastward, it is expected to become full absorbed into Typhoon Ma-on over the weekend.

Text credit:Rob Gutro, NASA Goddard Space Flight Center, Greenbelt, Md.




TRMM animated rainfall rates from Typhoon Ma-on on July 14, 2011 at 0525 UTC (1:25 a.m. EDT). › View TRMM animation
Rainfall rates from Typhoon Ma-on were animated on an image from the MODIS instrument on NASA's Aqua satellite on July 14, 2011 at 0525 UTC (1:25 a.m. EDT) . The rainfall rates were obtained from the TRMM satellite and showed heavy rainfall (red) around the center of circulation, with exception of the eastern side.
Credit: SSAI/NASA, Hal Pierce
The TRMM satellite flew over Ma-on on July 14, 2011 and noticed heavy rainfall around the center of circulation. › View larger image
The TRMM satellite flew over Ma-on on July 14, 2011 at 0525 UTC (1:25 a.m. EDT) and noticed heavy rainfall (red) around the center of circulation, with exception of the eastern side.
Credit: SSAI/NASA, Hal Pierce
TRMM Satellite Sees Very Heavy Rainfall in Typhoon Ma-On

The Tropical rainfall Measuring Mission satellite known as TRMM can measure rainfall from space, and data that it sent back to meteorologists reveal that the rain fall rate in Typhoon Ma-on are high.

The TRMM satellite passed almost directly above powerful typhoon Ma-on on July 14, 2011 at 0525 UTC (1:25 a.m. EDT). The TRMM orbit revealed that Ma-on was extremely well organized with numerous bands of intense thunderstorms around a well defined eye.

The rainfall analysis was created at NASA's Goddard Space Flight Center in Greenbelt, Md. using data from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR). It showed that the heaviest rainfall of over 50 mm/hr (~ 2 inches) was located in the southwestern quadrant of Ma-on's eye wall.

Ma-on is predicted to become an even more dangerous super typhoon with wind speeds of 135 kts (155 mph) on July 17, 2011 while approaching the islands of southern Japan.

Text credit:Hal Pierce, SSAI/NASA Goddard Space Flight Center, Greenbelt, Md.




















MODIS image showing Typhoon Ma-on on July 14 moving through the western North Pacific Ocean. › View larger image
This image was captured by the MODIS instrument that flies aboard NASA's Aqua satellite. It shows Typhoon Ma-on at 03:30 UTC on July 14 (11:30 p.m. EDT on July 13) moving through the western North Pacific Ocean, over the Northern Mariana Islands.
Credit: NASA Goddard/MODIS Rapid Response Team, Jeff Schmaltz
NASA Satellite Sees Typhoon Ma-on Soaking Guam

NASA satellite data shows Typhoon Ma-on soaking Guam, and the National Weather Service office there has issued an urban and small stream flood advisory for all of Guam until 2 a.m. CHST (local time) and a coastal hazard message and small craft advisories because of high waves and gusty winds.

Over the last couple of days, NASA satellite data from both the Tropical Rainfall Measuring Mission (TRMM) and Atmospheric Infrared Sounder (AIRS) that flies aboard Aqua detected powerful thunderstorms within Ma-on. Those thunderstorms contained heavy rainfall, falling at a rate of 2 inches/50 mm per hour. As NASA's Aqua satellite flew over Ma-on on July 14 (11:30 p.m. EDT on July 13), the Moderate Resolution Imaging Spectradiometer (MODIS) instrument captured a visible image of Typhoon Ma-on moving over the Northern Mariana Islands.

At 1500 UTC (11 a.m. EDT/1 a.m. Guam local time) on July 14, Typhoon Ma-on had maximum sustained winds near 95 knots (109 mph/175 kmh). It was located over the northern Marianas islands, about 250 nautical miles southeast of Iwo To, Japan near 20.3 North and 144.5 East. It was moving west near 11 knots (13 mph/20 kmh).

The National Weather Service flood advisory for today, July 14 at 11 a.m. Eastern Daylight Time (1 a.m. local time/Guam on July 15) noted that "additional rainfall amounts of 1 to 2 inches are possible during the next several hours. Recent heavy rains have left the ground saturated."

High surf conditions are also expected in Guam, Rota, Tinian and Saipan over the next several days. At 3:50 p.m. CHST (local time in Guam) on July 14 the National Weather Service (NWS) also issued a high surf advisory that will remain in effect through 6 a.m. (local time) on Sunday, July 17 as Ma-on passes through the region. The NWS advisory states that "Surf will build to hazardous at 7 to 9 feet along west facing reefs tonight and Friday. Surf will peak at 9 to 11 feet Friday night and Saturday, and should fall below 9 feet on Sunday." Beaches and exposed reefs are places to avoid through the advisory period, especially those facing the west as Ma-on continues to move in that direction. Rip currents are also possible.

There is also a small craft advisory in effect for the coastal waters of Guam, Rota, Tinian and Saipan until 6 p.m. (local time) Sunday as seas are expected to rise to 10 to 12 feet accompanied by winds between 20 and 25 knots (23-29 mph/37-46 kmh) through Saturday night.

Updated weather forecasts and advisories from the NWS for Guam can be found at: http://www.prh.noaa.gov/pr/guam/.

Text credit:Rob Gutro, NASA Goddard Space Flight Center, Greenbelt, Md.



July 13, 2011

AIRS showed Ma-on is steadily organizing and the strongest thunderstorms were on the southeastern side. › View larger image
When NASA's Aqua satellite passed over the eastern half of Typhoon Ma-on on July 13 at 14:53 UTC (10:53 a.m. EDT) it captured an infrared image of the temperatures of the eastern half of the cyclone's cloud tops that showed the storm is steadily organizing and the strongest thunderstorms (purple) were on the southeastern side.
Credit: NASA/JPL, Ed Olsen
NASA Satellite Imagery Confirms Ma-on Now a Typhoon

A large area of very cold, high thunderstorm cloud tops surround the center and the southeastern quadrant of the newly dubbed Typhoon Ma-on in the western North Pacific Ocean.

When NASA's Aqua satellite passed over the eastern half of Typhoon Ma-on on July 13 at 14:53 UTC (10:53 a.m. EDT) it captured an infrared image of the temperatures of the eastern half of the cyclone's cloud tops that showed the storm is steadily organizing. Ma-on became a typhoon earlier on July 13, 2011.

The Atmospheric Infrared Sounder (AIRS) instrument provided data on the clouds that showed they were very high and as cold as or colder than -63 Fahrenheit (-52 Celsius) the AIRS data threshold indicating strong thunderstorms around the center of circulation and in a large band of thunderstorms around the southeast of the center (the only quadrant of the storm with good outflow).

The forecasters at the Joint Typhoon Warning Center noted that the strong convection in the southeastern side of the storm was "robbing the core of energy" and had enabled faster intensification of the storm. In earlier imagery on July 18, an eye was visible when satellites passed over the center.

At 1500 UTC (11 a.m. EDT) on July 18, Typhoon Ma-on's maximum sustained winds were near 80 knots with higher gusts. The storm was about 570 nautical miles east-southeast of Iwo To, Japan near 19.8 North and 150.3 East. It was moving west at 11 knots and generating seas over 17 feet high.

Ma-on is continuing to intensify slowly, due to less than favourable atmospheric conditions. The storm will continue to move west-northwest, across the open Pacific. Later in the forecast period, Ma-on will veer north and is expected to make landfall in Japan in the course of next week, without weakening much beforehand.

Ma-on is expected to remain at sea over the next several days. On the 14th it will be well to the north of the island of Saipan, and by the 15th, it is forecast to be well south of Iwo To and Chichi Jima. However, those two islands will likely experience heavy surf from the east and south, showers and thunderstorms and gusty winds from the outer edges of the storm.

Text credit:Rob Gutro, NASA Goddard Space Flight Center, Greenbelt, Md.



July 12, 2011

Animation showing the rainfall occurring within Ma-on on July 12, 2011. › View animation
This animation shows the rainfall occurring within the storm on July 12, 2011. Click here to see an animation that shows TMI and PR rainfall being drawn over an image from TRMM's Visible and InfraRed Scanner (VIRS).
Credit: NASA/SSAI, Hal Pierce
Rainfall occurring in Ma-on when it was Tropical Depression 08W on July 11 at 0637 UTC (2:37 a.m. EDT). › View larger image
This is the rainfall occurring in Ma-on when it was Tropical Depression 08W on July 11 at 0637 UTC (2:37 a.m. EDT). The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches per hour. Red areas are heavy rainfall at almost 2 inches per hour.
Credit: NASA/SSAI, Hal Pierce
3-D look at the cloud heights and rainfall occurring in Ma-on when it was Tropical Depression 08W on July 11. › View larger image
This is a 3-D look at the cloud heights and rainfall occurring in Ma-on when it was Tropical Depression 08W on July 11 at 0637 UTC (2:37 a.m. EDT). The yellow and green areas indicate moderate rainfall between .78 to 1.57 inches per hour. Red areas are heavy rainfall at almost 2 inches per hour. The highest clouds were over 9 miles (15 km) high.
Credit: NASA/SSAI, Hal Pierce
TRMM Satellite Sees Intensification as Depression Becomes Tropical Storm Ma-on

Rainfall measurements taken from space have shown heavy rain within the newly named "Tropical Storm Ma-on" in the western North Pacific.

The Tropical Rainfall Measuring Mission (TRMM) satellite measures rainfall from space and noticed there were several areas where rains were heavy over the last two days. Heavy rain rates are about 2 inches/50 millimeters per hour. TRMM is a satellite that is managed by both NASA and the Japanese Space Agency.

Tropical storm Ma-on (formerly tropical depression 08W) developed east of the Marianas in the northern Pacific Ocean yesterday, July 11. It has continued to become more powerful in the last 24 hours Ma-on had wind speeds of about 35 knots (~40 mph/65 kmh) when TRMM saw the storm on July 12, 2011 at 0640 UTC (2:40 a.m. EDT).

Rainfall data from TRMM are used to create visualizations at NASA's Goddard Space Flight Center in Greenbelt, Md. Hal Pierce created various images using TRMM data that helped show where the strongest rainfall and most powerful thunderstorms are located within the tropical cyclone. TRMM Microwave Imager (TMI) and Precipitation Radar (PR) data were used in a rainfall analysis that was drawn on a Visible/Infrared (VIRS) image. The TMI data showed that Ma-on had heavy rainfall around the storms center of circulation and also in a large feeder band (of thunderstorms) converging into the eastern side of the storm.

At 1500 UTC (11 a.m. EDT) on July 12, Tropical Storm Ma-on's maximum sustained winds were near 35 knots (40 mph/65 kmh). It was located in the open waters of the western North Pacific, about 800 miles east-southeast of Iwo To, Japan, near 18.9 North and 154.4. East. It was moving to the west near 11 knots (12.6 mph/20 kmh).

On Monday July 11, 2011, TRMM had passed over Ma-on when it was weaker and still Tropical Depression 08W. It passed overhead at 0637 UTC (2:37 a.m. EDT) and showed that numerous convective thunderstorms were dropping moderate to heavy rainfall over a large area of the Pacific Ocean near 18.1N 157.3E.

TRMM data was also used to create a 3-D image that shows the structure of tropical depression 08W. Several thunderstorm towers within 08W reached heights of at least 15 kilometers (~9.3 miles) high.

Ma-on is predicted to gradually strengthen over the next five days. Ma-on is then expected to be a powerful typhoon with wind speeds of 95 kts (~109 mph) and be located in the open waters of the Pacific Ocean south of Japan.

Text credit:Hal Pierce, SSAI/NASA Goddard Space Flight Center, Greenbelt, Md.













July 11, 2011

AIRS captured TD08 showing the strongest thunderstorms (in purple) on the eastern and southern sides of it. ›View larger image
NASA's Aqua satellite passed over Tropical Depression 08W and captured an infrared image of the storm, identifying the coldest cloud tops, and therefore, the strongest thunderstorms (in purple), on the eastern and southern sides of it.
Credit: NASA JPL, Ed Olsen
New Tropical Depression 08W Has Strong T-Storms on 2 Sides

Infrared satellite data is helpful to forecasters in determining where the strongest thunderstorms are in a tropical cyclone through temperature. NASA satellite imagery confirmed those strongest storms in newborn Tropical Depression 08W were located on the southern and eastern sides of the storm.

Tropical Depression 08W formed in the western North Pacific Ocean during the morning hours (Eastern Daylight Time) on July 11. Its maximum sustained winds are near 30 knots (34 mph). It is currently located over open waters near 18.2 North and 157.3 East. That's about 775 nautical miles east-northeast of Andersen Air Base. It's moving to the west at about 3 knots (4 mph).

NASA's Aqua satellite passed over Tropical Depression 08W (TD08W) and captured an infrared image of the storm, identifying the coldest cloud tops, and therefore, the strongest thunderstorms, on the eastern and southern sides of it. The other interesting thing that the infrared data showed is that the center of the storm's circulation is somewhat elongated. When a storm is elongated, it doesn't tend to intensify as quickly as if it were rounded. Think of the performance of a storm like a tire. It would be like driving on a tire that's not exactly round. It would take you a lot longer to get somewhere, just as an elongated low pressure area is not spinning as efficiently as it could, allowing it to organize as quickly.

TD08W is in an area of low wind shear and warm waters, so those are two factors that will enable it to strengthen. The forecasters at the Joint Typhoon Warning Center noted all of these factors and the strong thunderstorms on the two sides of the storm, and created their forecast. The forecast calls for intensification over the next several days so it is likely going to reach tropical storm status in the next day.

Text credit:Rob Gutro, NASA Goddard Space Flight Center, Greenbelt, Md.