Typhoon Prapiroon brought wind and rain to Kyushu on Monday night. At 11:00 p.m. EDT on Monday the center of Typhoon Prapiroon was located at latitude 32.8°N and longitude 128.6°E which put it about 110 miles (180 km) southwest of Sasebo, Japan. Prapiroon was moving toward the north-northeast at 17 m.p.h. (27 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 968 mb.
Rainbands on the eastern side of Typhoon Prapiroon were moving over parts of Kyushu. Those bands were causing gusty winds and they were dropping locally heavy rain. The circulation of Typhoon Prapiroon was exhibiting the effects of a more midlatitude environment. Drier air was wrapping around the western and southern portions of the typhoon. The bands in those parts of Prapiroon consisted primarily of showers and low clouds. The western portion of the eyewall was also weakening. There were still strong thunderstorms in the eastern half of the eyewall and that was where the strongest winds were occurring. Several bands of showers and thunderstorms on the eastern side of the circulation were revolving around the core of Typhoon Prapiroon.
Typhoon Prapiroon will be moving through an environment that will cause it to weaken. Prapiroon was moving over water where the Sea Surface Temperature was near 26°C. However, it will move over water where the Sea Surface Temperature is near 24°C when it moves north of Japan. An upper level trough west of South Korea will produce southwesterly winds which will cause vertical wind shear. The combination of cooler water and more vertical wind shear will cause Typhoon Prapiroon to weaken to a tropical storm on Tuesday. Prapiroon could begin a transition to an extratropical cyclone because of the effects of the midlatitude environment.
Typhoon Prapiroon was being steered toward the north-northeast by the upper level trough. Stronger westerly winds will steer Prapiroon more toward the northeast when it gets north of Japan. On its anticipated track the center of Typhoon Prapiroon will pass near the northwestern portion of Kyushu. The center of Prapiroon is forecast to pass between south Korean and Japan and then to move over the Sea of Japan. Rainbands on the eastern side of Typhoon Prapiroon will cause gusty winds and drop heavy rain over parts of Kyushu. Heavy could cause flash floods in some locations. Prapiroon could also bring wind and rain to southeastern South Korea and parts of northern Honshu.
Elsewhere over the Western North Pacific Ocean Tropical Depression 10W formed southeast of Guam. At 11:00 p.m. EDT on Monday the center of Tropical Depression 10W was located at latitude 10.6°N and longitude 145.7°E which put it about 205 miles (330 km) south-southeast of Guam. It was moving toward the north-northwest at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1003 mb. A Tropical Storm Warning was issued for Guam. A Tropical Storm Watch was issued for Tinian and Saipan.