Strong thunderstorms reaching toward the top of the troposphere circled Tropical Storm Matmo's center and appeared in a band of thunderstorms on the storm's southwestern quadrant. Infrared imagery from NASA's Aqua satellite showed very cold temperatures that indicated the high cloud tops in the powerful storms.
Tropical cyclones consist of hundreds of thunderstorms. When NASA's Aqua satellite flew over Tropical Storm Matmo on July 17 at 16:59 UTC (12:59 p.m. EDT) on July 17, the Atmospheric Infrared Sounder (AIRS) instrument obtained infrared data on the tropical cyclone. AIRS showed some cloud top temperatures exceeded -63F/-52 C around the storm's center and in the southwestern quadrant of the storm indicating strong storms with the potential for heavy rainfall. The AIRS data was made into a false-colored image at NASA's Jet Propulsion Laboratory in Pasadena, California.
On July 18 at 1500 UTC (11 a.m. EDT) Tropical Storm Matmo's maximum sustained winds were near 40 knots (46 mph/74 kph). Matmo was located approximately 222 nautical miles (255.5 miles/411.1 km) north of Koror, Palau, centered near 11.2 north latitude and 133.5 east longitude. Matmo has tracked west-northwestward at 3 knots (3.4 mph/5.5 kph).
The Joint Typhoon Warning Center forecast indicates that Matmo will reach typhoon intensity by July 20 as it continues on a northwesterly track toward landfall in northern Taiwan around July 23 as a typhoon.
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