A NASA satellite captured an image of the western quadrant of Typhoon Matmo brushing over the eastern Philippines on July 20.
NASA's Terra satellite passed over Typhoon Matmo on July 20 at 02:15 UTC and the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard captured a visible image of the storm. The MODIS image showed a thick band of thunderstorms west of the storm's center were sweeping over the eastern Philippines.
The Joint Typhoon Warning Center (JTWC) noted that animated multispectral satellite imagery on July 21 showed that convection (rising air that forms thunderstorms) around the center of circulation had strengthened from the previous day. That stronger convection was evident in a thick band of thunderstorms in the southern quadrant of the storm that wrapped into the center. That same thick band of thunderstorms was also visible on the MODIS image of July 20.
On July 21 at 1500 UTC (11 a.m. EDT) Typhoon Matmo's maximum sustained winds were near 70 knots (80.5 mph/129.6 kph). Matmo was centered near 18.9 north latitude and 125.0 east longitude, about 500 nautical miles south-southwest of Kadena Air Base, Okinawa, Japan. Matmo is moving to the northwest at 11 knots (12.6 mph/20.3 kph) while intensifying. The Japan Meteorological Agency has issued a yellow alert advisory for Okinawa-honto Chiho that includes thunderstorms and high waves as Matmo draws nearer.
JTWC forecasters said that improving upper-level conditions and warm sea surface temperatures in the Philippine Sea are conducive for further intensification, and they expect Matmo's sustained winds to peak near 105 knots (120.8 mph/194.5 kph) sometime on July 23 as it approaches northern Taiwan.
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