Posted by JAC on 4/16/2009, 8:39 am, in reply to "Bijli forms from 94B in the Bay of Bengal"

The Northern Indian Ocean now has its first cyclone of their season. Cyclone 1B formed late on Tuesday, Apr. 14, Eastern Time. It has now strengthened from a low pressure area into a tropical depression and is expected to bring rains and gusty winds to the northeast coastal areas of India before moving away. Before Cyclone 1B strengthened into a tropical depression, the Joint Typhoon Warning Center (JTWC) labeled it System 94B. That was so the forecasters at JTWC could keep track of the storm. It just means that it’s the 94th low pressure area they've watched this season. On Apr. 15 at 09:00 UTC (5 a.m. EDT), Cyclone 1B had maximum sustained winds near 35 knots (40 mph) as confirmed by NASA's QuikSCAT satellite. Any strengthening will be slow to occur, because of adverse atmospheric conditions (i.e. wind shear – winds blowing in different directions at different heights in the atmosphere). It was moving northwest near 9 knots (10mph) towards the Indian coast. It is expected to brush the coast and then be pushed further east into the Bay of Bengal because of a developing high pressure system over India. Cyclone 1B was about 380 miles east-northeast of Chennai, India near 14.7 degrees north latitude and 86.6 degrees east longitude. That puts the center of the storm about west of center between India and Burma (or Myanmar) in the Bay of Bengal. According to the JTWC, the threatened landmasses include the Andaman Islands, India, Bangladesh, and Burma (Myanmar). There are already warnings posted for the Indian coast, and the Andaman Islands can expect gale force winds before 09:00 UTC on Apr. 16. The coasts of Orissa and Andra Pradesh may experience gales within the next day after. What NASA Satellite Imagery Shows Satellite imagery indicated strong convection (rapidly rising air that produces thunderstorms) in the northwest part of the cyclone. Cyclone 1B's clouds and thunderstorms can be seen in the latest visible and infrared images from NASA's Atmospheric Infrared Sounder (AIRS), an instrument that flies aboard NASA's Aqua satellite. The AIRS infrared image was created on Apr. 15 at 7:11 UTC (3:11 a.m. EDT) and shows the eastern half of the Cyclone, because its orbit wasn't centered over the storm. The AIRS image shows the temperature of Cyclone 1B's cloud tops and the surface of the Earth (where there are no clouds). The coldest cloud temperatures are in purple located to the northwest of the cyclone's center (where the strongest convection is occurring). Those areas in purple have some of the strongest thunderstorms. The second coolest temperatures are in blue, which make up the clouds outside of the center of circulation. The warmer temperatures of the ocean and land are shown orange and red. Notice the red-hot land temperatures in northern India. Text credit: Rob Gutro, NASA's Goddard Space Flight Center