Hurricane Season 2010: Tropical Depression 19W (Northwestern Pacific Ocean)

NASA's Aqua Satellite Sees Tropical Depression 19W in Two Seas

On Dec. 12 at 541 UTC (12:31 a.m. EST), the Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite captured an infrared image of Tropical Depression 19W's clouds, which were centered over Palawan. Palawan is an island province of the Philippines located in the Mimaropa region that stretches from southwest to northeast. Palawan lies between the South China Sea to its west and the Sulu Sea to its east, and Tropical Depression 19W's center was directly over Palawan at the time, and over both seas. AIRS data showed the thunderstorms in the center of Tropical Depression 19W's were as cold as or colder than -63 Fahrenheit, indicating strong storms.

Tropical Depression 19W (TD 19W) formed on Sunday, December 12 in the morning hours (UTC) and is headed west-northwest toward Vietnam. At time it formed, it was about 325 miles east of Ho Chi Minh, Vietnam. Today, December 13, at 0900 UTC (4 a.m. EST), TD 19W's maximum sustained winds had weakened to 20 knots (23 mph). It was about 225 nautical miles east of Ho Chi Minh City, Vietnam, near 10.3 North latitude and 110.1 East longitude. It was moving west-northwest at 5 mph.

Animated multispectral satellite imagery shows that TD 19W is now being buffeted by strong vertical wind shear (winds that can weaken a tropical cyclone and tear it apart), which is why it weakened since yesterday. Its low level-circulation center is now fully exposed to outside winds, and that's an indication that the system can weaken further. Satellite imagery from this morning indicates that convection (rapidly rising air that form the thunderstorms that power the tropical cyclone) are waning.

The Joint Typhoon Warning Center (JTWC) is the organization forecasting for TD 19W. JTWC is a joint United States Navy – United States Air Force task force located at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii.

JTWC expects TD 19W will continue to track west-northwestward and into an area of even strong vertical wind shear. As a result of those battering winds, TD 19W is expected to keep weakening until it makes landfall in southern Vietnam on December 14 at 0600 UTC (1 a.m. EST) far north of Ho Chi Minh.

Text Credit: Rob Gutro

NASA Goddard Space Flight Center, Greenbelt, MD