Winds blow off Omais' thunderstorm topsMarch 26, 2010 in Earth / Earth Sciences
Tropical Storm Omais is fading fast in the northwestern Pacific Ocean, and will dissipate over the weekend according to the Joint Typhoon Warning Center. When NASA's Aqua satellite flew over Omais late on March 25, it already showed signs of falling apart.
At 0900 UTC (5 a.m. EDT)on Friday, March 26, Tropical Storm Omais was barely hanging onto tropical storm strength with maximum sustained winds near 39 mph. It was located about 655 nautical miles southwest of the island of Iwo To (formerly Iwo Jima) near 18.3 North and 132.1 East. It was moving north-northeastward at 12 mph (11 knots) and quickly losing its tropical characteristics.
The infrared image from the Atmospheric Infrared Sounder (AIRS) instrument that flies on NASA's Aqua satellite captured an image of Omais on March 25 at 16:53 UTC (12:53 p.m. EDT) and revealed that its convection (rapidly rising air that creates the thunderstorms that power a tropical cyclone) was scattered and limited. It appears as if the convection center of circulation was blown apart - which is exactly what the wind shear had done to those high thunderstorm tops.
There is an upper level trough nearby and that has increased the vertical wind shear has elevated to near 46 mph (40 knots)! The system is expected to become fully extratropical on Saturday, March 27.
Provided by NASA's Goddard Space Flight Center
"Winds blow off Omais' thunderstorm tops" March 26, 2010 http://phys.org/news/2010-03-omais-thunderstorm-tops.html