Tropical Storm Sanvu is strengthening and imagery from NASA's Aqua satellite revealed what looks like a thick tail to the storm. The infrared data actually showed a thick feeder band of thunderstorms wrapping into the low-level center of circulation.
The Atmospheric Infrared or AIRS instrument aboard NASA's Aqua satellite captured infrared data on Tropical Cyclone Sanvu on Aug. 29 at 11:47 a.m. (1547 UTC). Infrared data provides temperature information to scientists. Cloud top temperatures are an important factor when it comes to determining the strength of storms. The higher the cloud tops, the colder and the stronger the storms.
The image showed that the coldest cloud tops were colder than minus 63 degrees Fahrenheit (minus 53 degrees Celsius). Those storms were found around the center of circulation and in a thick feeder band of thunderstorms from the southwest of the center.
NASA research has shown that storms with cloud tops that cold, reached high into the troposphere and had the ability to generate heavy rain.
At 11 a.m. EDT (1500 UTC) on Aug. 30 the center of Sanvu was located near 27.1 degrees north latitude and 142.9 degrees east longitude. That puts the center about 37 nautical miles east of Chichi Jima, Japan. Maximum sustained winds were near 55 knots (63 mph/102 kph). Sanvu was moving to the west-northwest at 16 knots (18.4 mph/29.3 kph).
The Joint Typhoon Warning Center expects Sanvu to intensify to typhoon status by before becoming extra-tropical.