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Hurricane Season 2010: Typhoon Megi (Northwest Pacific Ocean)
10.27.10
 
October 27, 2010

NASA Map Tracks Heavy Rainfall From Typhoon Megi

Rain map showing heavy rain Super-typhoon Megi unleashed as it tracked west across the Pacific from October 13-23, 2010. › View larger image
NASA's TRMM satellite data helped create this rain map showing heavy rain Super-typhoon Megi unleashed as it tracked west across the Pacific between October 13 and October 23, 2010. The heaviest rainfall—more than 600 millimeters or nearly 24 inches—appears in dark blue. The lightest rainfall—less than 75 millimeters or 3 inches—appears in light green.
Image Credit: NASA, Earth Observatory, Jesse Allen
Though a storm’s strength is gauged by wind speed, tropical cyclones also pose a hazard because of the intense rain they bring to a region. This image shows the heavy rain Super-typhoon Megi unleashed as it tracked west across the Pacific between October 13 and October 23, 2010. The heaviest rainfall—more than 600 millimeters or nearly 24 inches—appears in dark blue. The lightest rainfall—less than 75 millimeters or 3 inches—appears in light green.

The storm’s track is superimposed on the rainfall map. Megi formed as a tropical depression over the western Pacific Ocean on October 13, 2010. It quickly strengthened to a named storm, and three days after forming, had grown to a super typhoon. In general, rainfall roughly matches the storm track, especially west and northwest of the Philippines.

Over the northern Philippines, Megi cut a wide swath of destruction, destroying homes and accounting for at least 28 deaths, according to the Associated Press. As the storm track indicates, Megi reached its greatest intensity immediately east of the Philippines. The storm weakened slightly after October 17, but remained powerful across the northern Philippines.

Over the South China Sea, Megi re-strengthened somewhat before making landfall along the Chinese coast. The storm dropped heavy precipitation along a curving path between the Philippines and China.

Away from the storm track, areas of heavy rainfall appear east of Taiwan, where torrential rains led to deadly landslides. The Associated Press reported that, as of October 24, floods and landslides had killed as many as 31 people in that island nation. United Daily News reported that the heavy rains in Taiwan might have resulted from interactions between Megi and monsoon weather patterns northeast of the storm.

This image is based on data from the Multisatellite Precipitation Analysis produced at NASA's Goddard Space Flight Center, which estimates rainfall by combining measurements from many satellites and calibrating them using rainfall measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite.

Text Credit: Michon Scott
NASA's Earth Observatory
NASA Goddard Space Flight Center, Greenbelt, MD



October 25, 2010

NASA Microwave Imagery Showed Cold, High Thunderstorms as Typhoon Megi Made Landfall

The area that is shaded purple means the microwave cannot penetrate below 35,000 ft, (~200 millibars); that is close to the tropopause. › View larger image
This NASA microwave image of Megi shows cold areas (yellow-green) where there is precipitation or ice in the cloud tops in cold, high thunderstorms. The area that is shaded purple (T = 220 K = -53 C = -63 F) means the microwave cannot penetrate below 35,000 ft, which is an approximate pressure of 200 millibars. That is close to the tropopause.
Image Credit: NASA/JPL, Ed Olsen
Microwave imagery created from two NASA satellite instruments showed that Typhoon Megi had very high, cold thunderstorms as its center was about to make landfall on October 23.

Microwave images are created when data from NASA's Aqua satellite Atmospheric Infrared Sounder (AIRS) and Advanced Microwave Sounding Unit (AMSU) instruments are combined. The cold areas in a microwave image from Oct. 23 at 18:05 UTC (2:05 p.m. EDT) indicated precipitation was falling from Taiwan (east) westward into mainland China.

The microwave image suggested cold, high thunderstorms as the center of Megi was approaching a landfall in southeastern China. The coldest area of cloudtops were as cold as 220 Kelvin, or -53 Celsius or -63 Fahrenheit. In that area, the microwave could not penetrate below 35,000 ft, which is an approximate pressure of 200 millibars (close to the tropopause).

According to news sources, no casualties were reported in Xiamen. Xiamen, also known as Amoy is a coastal city in southeastern China. There were some reports of temporary flooding, and a couple of thousand stranded travelers. Megi did damage more than 500 homes and forced evacuations of more than 300,000.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, MD



October 22, 2010

NASA Satellites See Typhoon Megi Poised for Southeastern China Landfall

Megi contained powerful thunderstorms rotating around a large distinct circular eye. › View larger image
This TRMM image on Oct. 21 at 1401 UTC (10:01 a.m. EDT) showed Megi contained powerful thunderstorms rotating around a large distinct circular eye. The heaviest rainfall (red) falling at 2 inches per hour, was located in bands to the east of Megi's eye.
Image Credit: NASA/SSAI, Hal Pierce
On Oct 22, the western edge of Megi's clouds were already over southeastern China. › View larger image
The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard NASA's Aqua satellite captured a visible image of Typhoon Megi's clouds at 05:15 UTC on Oct 22. The western edge of Megi's clouds were already over southeastern China.
Image Credit: NASA Goddard MODIS Rapid Response Team
Typhoon Megi has run into winds that are weakening the storm, but it is forecast to make landfall in southeastern China late at night (EDT) on Oct. 22 (11 a.m. local time Hong Kong, Oct. 23) as a Category One Typhoon. NASA satellites have been monitoring the storm's rainfall, changing cloud cover, and changing eye as it weakens.

The Tropical Rainfall Measuring Mission (TRMM) satellite traveled directly above Megi on October 21 at 1401 UTC (10:01 a.m. EDT) when wind speeds were estimated to be about 100 knots (~115 mph). Megi caused at least 27 deaths in the Philippines and is now headed directly toward southern China when the TRMM satellite captured data on the storm's rainfall.

TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data were used to make a precipitation analysis that was overlaid on a TRMM Infrared image at NASA's Goddard Space Flight Center in Greenbelt, Md. The TRMM image showed Megi contained powerful thunderstorms rotating around a large distinct circular eye. The TRMM rainfall analysis showed that the heaviest rainfall, falling at about 2 inches per hour was located in bands of thunderstorms to the east of Megi's eye.

Because wind shear has increased today, Oct. 22, the storm continues to weaken. Satellite data indicates that convection (rapidly rising air that form the thunderstorms that power the typhoon) is weaker today than yesterday, also indicating a weakening storm. Further, the large eye has now completely filled with clouds.

On Friday, Oct. 22 at 1500 UTC (11 a.m. EDT) Typhoon Megi's maximum sustained winds had decreased to 90 knots (103 mph), making Megi a Category Two typhoon on the Saffir-Simpson Scale. It was located about 235 nautical miles east of Hong Kong near 22.6 North and 118.3 East. It was moving North at 7 mph (6 knots) and is expected to make landfall in southeastern China by 11 p.m. tonight (EDT), or 11 a.m. on Saturday, Oct. 23 local time in Hong Kong.

The Joint Typhoon Warning Center forecasts a landfall late at night on Oct. 22 (Eastern Daylight Time). After landfall, Megi is expected to dissipate quickly and merge with a stationary frontal boundary.

Text Credit: Rob Gutro and Hal Pierce
NASA Goddard Space Flight Center, Greenbelt, MD



October 21, 2010

NASA Sees Large and Powerful Typhoon Megi Fill Up Half of the South China Sea

The large area of powerful thunderstorms circling Typhoon Megi's large eye have cloud tops as cold as or colder than -65 degrees Fahrenheit › View larger image
NASA's AIRS instrument infrared image from October 20 at 05:23 shows Typhoon Megi filling up half of the South China Sea. The large area of powerful thunderstorms (purple) circling Typhoon Megi's large 40 nm eye have cloud tops as cold as or colder than -65 degrees Fahrenheit (-53 Celsius).
Image Credit: NASA/JPL, Ed Olsen
Typhoon Megi is a huge and powerful typhoon and NASA satellite imagery revealed that the storm's clouds extend over about half of the South China Sea.

The South China Sea is part of the Pacific Ocean, and ranges from the Singapore and Malacca Straits to the Strait of Taiwan of around 3,500,000 km² (1,351,000 square miles). Depending on measurement, the South China Sea is the largest or second largest body of water following the five oceans.

Infrared imagery captured by the Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite showed the huge extent of the typhoon. AIRS measures cloud-top temperatures, and the colder the cloud tops, the higher they are in the troposphere, and stronger the thunderstorms are associated with those cloud tops.

In AIRS imagery from October 20 at 05:23 UTC (1:23 a.m. EDT), a large area of thunderstorms around Megi's eye covering hundreds of miles had very cold cloud tops as cold as or colder than -65 degrees Fahrenheit (-53 Celsius). Those very cold cloud tops indicated the thunderstorms were powerful and we big rainmakers.

Megi's eye that measured 40 nautical miles this morning and the large area that the entire storm covered. AIRS data showed the eastern extent of Megi's clouds over the northwestern Philippines. The northern extent of Megi's clouds were just south of Taiwan, and the western extent was just shy of the southeastern China mainland and Hainan Island. Megi's southernmost clouds extended almost to Brunei and Vietnam.

Typhoon Megi has maximum sustained winds of 95 knots (109 mph). It was centered about 245 miles southeast of Hong Kong, China near 20.2 North and 117.7 East. It was moving north at 5 knots (6 mph). As it continues tracking north wind shear is expected to increase along the southern coast of China weakening the typhoon. However, the Joint Typhoon Warning Center who forecasts tropical cyclones in this area of the world notes that the system will maintain typhoon strength till landfall.

Residents of southeastern China can expect typhoon-force winds, heavy surf and heavy rainfall as Typhoon Megi approaches and makes landfall. Once Typhoon Megi makes landfall in southeastern China (by 5:30 p.m. EDT on October 22) it will dissipate within a day or two.

Text Credit: Rob Gutro
NASA Goddard Space Flight Center, Greenbelt, MD