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Hurricane Season 2010: Tropical Storm Malakas (Northwest Pacific Ocean)
09.24.10
 
September 24, 2010

NASA's CloudSat satellite Sees a Powerful Heat Engine in Typhoon Malakas

CloudSat  captured an image of Typhoon Malakas on Sept. 23 › View larger image
CloudSat captured an image of Typhoon Malakas at12:09 a.m. EDT on Sept. 23 that indicated strong convection on either side of the storm eyewall, with maximum cloud top heights around 9.3 miles (15 kilometers) in the southern quadrant of the storm, and approaching 10 miles (16 km) in the northern quadrant. Credit: NASA/JPL/Colorado State University/Naval Research Laboratory-Monterey
Towering thunderstorms and heavy rainfall are two things that NASA's CloudSat satellite saw as it passed over Typhoon Malakas, and those two factors confirm a strong storm. NASA's CloudSat satellite's Cloud Profiling Radar can basically slice a tropical cyclone in half and take a look at its clouds and rainfall, and that's what it did when it passed over Typhoon Malakas on Sept. 23.

CloudSat flew over Typhoon Malakas during the daytime on Sept. 23. At that time, Malakas had a minimum central pressure of 965 millibars, maximum winds of around 115 mph (100 knots), and a storm width (winds greater than or equal to 57 mph or 50 knots) of around 150 nautical miles.

Dr. Matt Rogers, a research scientist who works on the CloudSat team at the Dept. of Atmospheric Science, Colorado State University, Fort Collins, Colo. noted that the " CloudSat overpass of the typhoon occurred around 4:09 GMT (12:09 a.m. EDT/1:09 p.m. local time/Japan), and radar imagery of the typhoon indicated strong convection on either side of the storm eyewall, with maximum cloud top heights around 9.3 miles (15 kilometers) in the southern quadrant of the storm, and approaching 10 miles (16 km) in the northern quadrant."

A strong convective (rapidly rising air that creates the thunderstorms that power a tropical cyclone) cell dominates the northern quadrant of the storm, while several smaller convective cells combine to make up the southern quadrant, according to the CloudSat overpass.

"The presence of heavy rainfall near the storm core causes radar attenuation - a condition that occurs when the vast amount of water present in the storm scatters or absorbs all available radar energy, leaving no signal to return to the satellite," Rogers said.

Satellite data also detected an eye 50 nautical miles wide, and around it were the strong thunderstorms wrapping around it and into the storm's center from the southeastern quadrant.

At 1500 UTC (11 a.m. EDT) on Sept. 24, Typhoon Malakas has maximum sustained winds near 103 mph (90 knots). It was located about 75 nautical miles west-northwest of Chi Chi Jima, Japan near 29.8 North and 142.4 East. It was moving north-northeast near 26 mph (23 knots) and kicking up 31-foot high seas.

Malakas has tracked over Iwo To and Chi Chi Jima and is now headed into open waters this weekend. It is forecast to stay at sea and away from land, paralleling the coast of Japan. By Saturday, Malakas is forecast to start transitioning into an extra-tropical storm and weaken gradually. As it continues northeast it will encounter stronger vertical westerly wind shear which will help weaken the system somewhat, but it is forecast to still remain an intense storm after the transition.

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



September 23, 2010

NASA Sees Important Cloud-Top Temperatures as Tropical Storm Malakas Heads for Iwo To

This AIRS image shows a very large area of high, cold cloud tops throughout Tropical Storm Malakas. › View larger image
This infrared image of Malakas' cloud temperatures was captured on Sept. 23 at 0405 UTC (12:05 a.m. EDT) by the AIRS instrument on NASA's Aqua satellite. The image shows a very large area of highest, coldest cloud tops (colder than -63 Fahrenheit) throughout Tropical Storm Malakas (in purple).
Credit: NASA/JPL, Ed Olsen
NASA's Aqua satellite has peered into the cloud tops of Tropical Storm Malakas and derived just how cold they really are, giving an indication to forecasters of the strength of the storm.

The Atmospheric Infrared Sounder instrument, known as AIRS has the ability to determine cloud top and sea surface temperatures from its position in space aboard NASA's Aqua satellite. Cloud top temperatures help forecasters know if a storm is powering up or powering down.

When cloud top temperatures get colder it means that they're getting higher into the atmosphere which means the "uplift" of warm, moist air is stronger and it will form stronger thunderstorms (that power a tropical cyclone). When cloud-top temperatures warm up it means that the cloud tops are lower than they were before, indicating that the storm is weakening.

When the Aqua satellite passed over Malakas from space on Sept. 23 at 0405 UTC (12:05 a.m. EDT) the AIRS instrument took the temperature of the cloud tops in the storm and found them to be as cold as or colder than -63 Fahrenheit throughout a very large area within Tropical Storm Malakas, indicating the storm had a good amount of energy powering it. Infrared imagery also showed an eye with thunderstorms banding around it (circling it), and convection (and thunderstorms) re-building over the system, which indicates strengthening.

The Joint Typhoon Warning Center is the organization that forecasts tropical cyclones in the northwestern Pacific Ocean, and they've been right on track with Tropical Storm Malakas' forecast, much to the disappointment of the residents of the Japanese island of Iwo To. That's where Malakas' center is expected to pass very closely near later tonight (Eastern Time/U.S.).

On Sept. 23 at 1500 UTC (11 a.m. EDT/midnight Sept. 24 local time at Iwo To), Malakas had maximum sustained winds near 69 mph (4 mph under typhoon strength). It was moving north at 14 mph toward Iwo To, Japan. It was located about 170 nautical miles south of the island, near 22.6 North and 140.9 East. Malakas is kicking up 27-foot high seas as it tracks north.

The center of Malakas is forecast to be closest to the island of Iwo To at 0000 UTC (about 9 a.m. Local time) on Sept. 24 (8 p.m. EDT on Sept. 23).

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



September 22, 2010

NASA's Infrared Imagery Sees Powerful Thunderstorms in Tropical Storm Malakas

This infrared image of the eastern half of Tropical Storm Malakas showed cold, high thunderstorms in the storm's center (purple). › View larger image
This infrared image of the eastern half of Tropical Storm Malakas showed cold, high thunderstorms in the storm's center (purple). The image was taken from NASA's Aqua satellite on Sept. 22 at 0317 UTC.
Credit: NASA/JPL, Ed Olsen
Tropical Storm Malakas is spinning through the northwestern Pacific Ocean and NASA infrared satellite imagery revealed powerful thunderstorms in its center.

Infrared satellite imagery can measure cloud top temperatures and determine if the thunderstorms in a tropical cyclone are getting stronger, and that's what an instrument on NASA's Aqua satellite did with Tropical Storm Malakas. NASA's Aqua satellite captured an infrared image of the eastern half of Tropical Storm Malakas. Malakas had cold, high thunderstorms on Sept. 22 at 0317 UTC (Sept. 21 at 11:17 p.m. EDT) in its center.

At 1200 UTC (8 a.m. EDT) on Sept. 22, Tropical Storm Malakas had maximum sustained winds near 46 mph, and is located about 300 nautical miles south of Iwo To, Japan near 20.1N and 141.6E. It is moving northwestward near 7 mph.

Malakas's low level center of circulation is partially exposed, and it is dealing with northerly vertical wind shear, which is preventing it from intensifying.

Malakas is expect to slowly strengthen as the wind shear eases and it is forecast to reach typhoon strength. After passing Iwo To, it is forecast to turn to the northeast and become extra-tropical.

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



September 21, 2010

NASA Infrared Imagery Shows Strength in 13W As it Becomes Tropical Storm Malakas

Infrared image of Tropical Storm Malakas from the AIRS instrument aboard NASA's Aqua satellite. › View larger image
This infrared image of Tropical Storm 13W from the AIRS instrument aboard NASA's Aqua satellite shows that the strongest convection, highest thunderstorms and heaviest rainfall on Sept. 20 at 15:41 UTC (11:415 a.m. EDT) were concentrated in the system's center and northeastern quadrants (purple) where cloud top temperatures were as cold as -65 Fahrenheit, indicating strong thunderstorms.
Credit: NASA/JPL, Ed Olsen
The Atmospheric Infrared Sounder (AIRS) Instrument on NASA's Aqua satellite is a good gauge for scientists to determine if a tropical cyclone is strengthening, by seeing if their cloud top temperatures have cooled. Cooler cloud top temperatures indicate that the cloud tops are higher in the atmosphere and indicate there's strong convection happening. That's what NASA infrared data showed today as tropical storm 13W became Tropical Storm Malakas in the Northwestern Pacific Ocean.

The Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite captured cloud top temperatures of Tropical Storm Malakas on Sept. 20 at 15:41 UTC (11:41 a.m. EDT). At that time, infrared imagery showed the strongest convection, highest thunderstorms and heaviest rainfall were concentrated in the system's center and northeastern quadrant. Those cloud top temperatures were as cold as -65 Fahrenheit indicating strong thunderstorms. Since yesterday, Malakas' cloud top temperatures cooled which indicates that the thunderstorms within the storm are higher, colder and stronger than they were yesterday.

Malakas had maximum sustained winds near 48 mph (40 knots) at 10 a.m. EDT on Sept. 21. It was moving slowly north-northeast at 5 mph. Malakas is located about 230 nautical miles north-northwest of Saipan, near 19.1 North and 144.5 East. Currently Malakas' forecast track takes it close to Iwo To and Chi Chi Jima by Friday.

Forecasters at the Joint Typhoon Warning Center are forecasting a northwesterly track that would affect Iwo To and Chi Chi Jima this week.

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



September 20, 2010

NASA Infrared Sees Strong Thunderstorms in Newly Formed Tropical Depression 13W

Infrared image of Tropical Depression 13W from the AIRS instrument aboard NASA's Aqua satellite › View larger image
This infrared image of Tropical Depression 13W from the AIRS instrument aboard NASA's Aqua satellite shows that the strongest convection, highest thunderstorms and heaviest rainfall on Sept. 20 at 03:29 UTC (11:29 p.m. EDT, Sept. 19) were concentrated in the system's center (purple). Those cloud top temperatures were as cold as or colder than -60 Fahrenheit, indicating strong thunderstorms.
Credit: NASA/JPL, Ed Olsen
The thirteenth tropical depression in the Northwestern Pacific hurricane season formed today, and NASA's infrared satellite imagery noticed some powerful thunderstorms in the system's center.

An infrared image of Tropical Depression 13W was captured from the Atmospheric Infrared Sounder (AIRS) instrument shortly after it was "born" early this morning. AIRS flies aboard NASA's Aqua satellite. The infrared imagery shows temperatures, from cold cloud tops to warm sea surface temperatures that power tropical cyclones. Today's image showed that the strongest convection, highest thunderstorms and heaviest rainfall were concentrated in the system's center. Those cloud top temperatures were as cold as or colder than -60 Fahrenheit, indicating strong thunderstorms.

Tropical Depression 13W (TD13W) had maximum sustained winds near 34 mph. TD13W was located approximately 225 nautical miles north of Saipan, near 18.7 North and 145.2 East. It has moved northwestward at 7 mph and is creating 12- foot high waves.

Forecasters at the Joint Typhoon Warning Center are forecasting a northwesterly track that would affect Iwo To and Chi Chi Jima this week.

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