NASA's Aqua satellite saw the massive Typhoon Nangka moving out of the Marianas Islands, while NASA's RapidScat instrument pinpointed the location of its strongest winds.
On July 9, the RapidScat instrument that flies aboard the International Space Station, observed Nangka's strongest winds on the western side of the storm, reaching speeds of more than 30 meters per second (108 kph/67 mph). RapidScat scanned the storm's surface winds for about 90 minutes from 1:41 p.m. to 3:14 p.m. EDT.
When Aqua passed over Typhoon Nangka on July 10 at 01:10 UTC (9:10 a.m. EDT on July 9), MODIS captured a visible-light image of the storm that showed a cloud-filled eye. The Joint Typhoon Warning Center (JTWC) noted that animated infrared satellite imagery shows a weakening system with a cloud-filled eye and spiral banding of thunderstorms located mostly over the southern semi-circle due to increasing northerly vertical wind shear.
Nangka was a Super typhoon, but weakened to typhoon status. "Super-typhoon" is a term utilized by the U.S. Joint Typhoon Warning Center for typhoons that reach maximum sustained 1-minute surface winds of at least 65 m/s (130 kt, 150 mph). This is the equivalent of a strong Saffir-Simpson category 4 or category 5 hurricane in the Atlantic basin or a category 5 severe tropical cyclone in the Australian basin.
On July 9 at 1500 UTC (11 a.m. EDT), Typhoon Nangka had maximum sustained winds dropped to near 110 knots (126.6 mph/203.7 kph) It was centered 18.3 North latitude and 140.9 East longitude, about 890 nautical miles (1,024 miles/1,648 km) east-southeast of Kadena Air Force Base, Japan. It was moving to the west at 8 knots (9.2 mph/14.8 kph) and is generating rough seas with waves to 40 feet (12.1 meters).
Nangka will continue to move west-northwest while steadily weakening over the next couple of days before re-strengthening. The Joint Typhoon Warning Center track takes the storm near the island of Amami Oshima by July 15.