Hurricane Season 2010: Tropical Storm 94B (Northern Indian Ocean)

NASA's Infrared Satellite Imagery Shows Strong Convection in System 94B

A low pressure system has been moving through the Northern Indian Ocean over the last couple of days and infrared satellite imagery from NASA's Aqua satellite revealed strong convection in its eastern side and strong wind shear.

At 1800 UTC (1 p.m. EST) on Dec. 6, the center of the low pressure area known as 94B was located east of India's southeast coast over the Bay of Bengal. 94B's center is about 225 miles northeast of Colombo, Sri Lanka near 11.4 North and 84.0 East.

When NASA's Aqua satellite passed over the low on Dec. 6 at 07:59 UTC (2:59 a.m. EST), its Atmospheric Infrared Sounder (AIRS) instrument captured an infrared image of the storm's clouds. The image revealed that the western half of the low is already over land as a result of strong wind shear, while the eastern half of the storm and its center of circulation are over open waters in the Bay of Bengal. AIRS data showed that the eastern half of the low had the strongest convection and thunderstorms as infrared data revealed that cloud tops are so high that they are at least -63 degrees Fahrenheit (-52 Celsius) or colder.

Vertical wind shear in the area is moderate to strong, so the convection and strongest thunderstorms have been pushed to the northwest of the center as a result of those strong southeasterly winds.

Because of the wind shear and its proximity to the coast, chances are poor that it will consolidate into a tropical cyclone. The minimum sea level pressure in the vicinity of the storm is estimated to be near 1004 millibars.

Despite the fact that it may never become organized enough to be classified a tropical depression, it will still bring periods of moderate rainfall and some gusty winds to the coastal areas. Some gusts could be as strong as 25 knots (28 mph/ 46 km/hour). The forecast for Pondicherry, which is located in the southeastern region of India calls for widely scattered showers and thunderstorms over the next couple of days from this system. Pondicherry is a city, an urban agglomeration and a municipality in Pondicherry District in the union territory of Puducherry and residents should keep an eye on System 94B as it approaches.

Text Credit: Rob Gutro

NASA Goddard Space Flight Center, Greenbelt, MD