Warnings are still in effect in the northern Philippines and now in Hong Kong, as Tropical Storm Kai-tak continues to drop heavy rainfall and move toward a landfall in China. NASA's Aqua satellite captured infrared data that shows a large area of strong thunderstorms that make up Kai-tak.
NASA's Aqua satellite captured infrared data on Kai-tak when it passed overhead on August 15 at 0517 UTC (1:17 a.m. EDT/1:17 p.m. local time, Hong Kong). Forecasters at the Joint Typhoon Warning Center noted that infrared satellite imagery shows the organization near the center of Kai-tak's tightly wrapped low-level-circulation center suffered some minor degradation during the early part of August 15. The Atmospheric Infrared Sounder (AIRS) instrument that flies onboard NASA's Aqua satellite provides infrared data and showed a large area of cold cloud top temperatures (a sign of more uplift and strength in the storm) west of Kai-tak's center. The strongest thunderstorms and coldest cloud top temperatures stretched from northern Luzon, west into the South China Sea. Satellite data shows a lack of convection (rising air that forms the thunderstorms that make up the tropical storm) around the northern periphery of the storm.
The winds of Tropical storm Kai-tak, known in the Philippines as Helen, have increased to 55 knots (63 mph/102 kmh) on August 15. Kai-tak is located near 19.5 North latitude and 119.0 East longitude, about 320 nautical miles (368 miles/592.6 km) east-southeast of Hong Kong. Kai-tak is moving to the west-northwest near 17 knots (19.5 mph/31.5 kmh).
Kai-tak continues moving northwest and is passing over northern Luzon today, August 15, 2012. Warnings are still in effect in Luzon, the Philippines and now in effect in Hong Kong, China.
Current warnings in effect in the Philippines on August 15 include: Public storm warning signal #1 for the Luzon provinces of Benguet, Ifugao, Isabela, La Union, Northern Aurora, Mountain Province, Nueva Vizcaya, Quirino, and Pangasinan. In addition, Public storm warning signal #2 is in effect for these Luzon provinces: Apayao and Abra, the Batanes Group of Islands, Cagayan, Calayan, Babuyan Group of Islands, Kalinga and Ilocos North and South.
In Hong Kong, the Stand-by signal 1 is in force. After passing over the South China Sea, it will come ashore near Hong Kong at typhoon strength. Landfall is expected to occur near Hong Kong tomorrow, Thursday, August 16 near 1200 UTC (8 a.m. EDT/8 p.m. local time, Hong Kong). Forecasters at the Joint Typhoon Warning Center note that warm waters off-shore may cause Kai-tak to intensify to typhoon strength just before it makes landfall.
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