Infrared NASA imagery shows development of Tropical Depression 31W

NASA's Aqua satellite provided infrared imagery of the latest tropical cyclone in the South China Sea.

The Atmospheric Infrared Sounder aboard NASA's Aqua satellite captured an infrared image of Tropical Depression 31W on Nov. 17 at 12:17 a.m. EST (0517 UTC). Infrared data provides cloud top temperatures and the coldest cloud tops and strongest storms were in the eastern part of the South China Sea. Some of those storm cloud tops were as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius). NASA research has shown that storms with cloud tops that cold have the potential to generate heavy rainfall.

The Joint Typhoon Warning Center reported "animated enhanced infrared satellite imagery shows poorly organized, fragmented, and shallow, albeit formative convective bands loosely feeding into a weak and obscured low level circulation."

On Nov. 17 at 10 a.m. EST (1500 UTC) the Joint Typhoon Warning Center noted that 31W had maximum sustained winds near 25 knots (27.7 mph). 31W was centered near 10.4 degrees north latitude and 117.4 degrees east longitude. That's about 50 nautical miles north-northwest of Puerto Princesa, Palawan, Philippines. 31W was moving to the northwest at 16 knots (18.4 mph/29.6 kph).

The Joint Typhoon Warning Center expects 31W to strengthen into a tropical storm by Nov. 18 and peak at 45 knots the next day before beginning a weakening trend.

31W is forecast to make landfall in southeastern Vietnam on Nov. 19.