Tag Archives: Tropical Depression 13W

Tropical Storm Krosa Passes East of Japan

Tropical Storm Krosa passed east of Japan on Friday.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Krosa was located at latitude 36.8°N and longitude 143.4°E which put the center about 130 miles (210 km) east-northeast of Tokyo, Japan.  Krosa was moving toward the north-northeast at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 972 mb.

Tropical Storm Krosa passed east of Japan on Friday.  Even though Krosa was a tropical storm, there was a clear area at the center of its circulation.  The clear area was surrounded by a broken ring of thunderstorms.  The strongest winds were occurring in that broken ring of storms.  Thunderstorms were occurring in bands in the eastern side of Tropical Storm Krosa. Bands in the western side of Krosa’s circulation consisted primarily of showers and lower clouds.

The distribution of wind speeds in Tropical Storm Krosa was more symmetrical on Friday.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Krosa’s circulation.

Tropical Storm Krosa will move through an environment unfavorable for the intensification of a tropical cyclone during the next 24 hours.  Krosa will move over water where the Sea Surface Temperatures are near 26°C.  It will move under the eastern side of an upper level trough that is north of Japan.  The upper level trough will produce southwesterly winds that will cause moderate vertical wind shear.  Cooler Sea Surface Temperatures and moderate vertical wind shear will cause Tropical Storm Krosa to start a transition to an extratropical cyclone during the next 24 hours.

The upper level trough north of Japan will steer Tropical Storm Krosa toward the east-northeast during the next 24 hours.  On its anticipated track, Tropical Storm Krosa will move away from Japan.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 13W formed south of Japan.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 13W was located at latitude 28.1°N and longitude 137.5°E which put the center about 325 miles (520 km) west-northwest of Iwo To.  Tropical Depression 13W was moving toward the northeast at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 998 mb.

Tropical Storm Ampil Moves Over Okinawa

Tropical Storm Ampil moved over Okinawa on Friday night.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Ampil was located at latitude 27.3°N and longitude 127.4°E which put it about 25 miles (40 km) north-northwest of Okinawa.  Ampil was moving toward the northwest at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 990 mb.

Drier air continued to circulated around Tropical Storm Ampil on Friday and the drier air prevented Ampil from intensifying.  Several bands of stronger thunderstorms were occurring northeast of the center of circulation and the strongest winds were occurring in those bands.  The bands in other parts of Tropical Storm Ampil consisted primarily of the showers and low clouds.  There was a distinct low level center of circulation, but there were few thunderstorms near the center.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Tropical Storm Ampil is unlikely to intensify significantly before it makes landfall in China.  Ampil will move over water where the Sea Surface Temperature is near 28°C.  So, there will be enough energy in the ocean to support intensification.  There is a chance for some intensification on Saturday, if more thunderstorms develop near the center of circulation.  However, the drier air will inhibit the formation of taller thunderstorms and that will limit possible intensification..

Tropical Storm Ampil will move south of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Ampil quickly toward the northwest.  On its anticipated track Tropical Storm Ampil will move quickly away from Okinawa and the Ryukyu Islands.  Ampil could approach the coast of China near Shanghai in about 24 hours.  Tropical Storm Ampil will bring gusty winds and locally heavy rain to the region of China around Shanghai.

Elsewhere over the Western North Pacific Ocean Tropical Depression 13W formed west of northern Luzon.  At 11:00 p.m. EDT on Friday the center of Tropical Depression 13W was located at latitude 18.0°N and longitude 118.9°E which put it about 140 miles (225 km) west of Laoag, Philippines.  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 998 mb.  The depression could bring locally heavy rain and cause flash floods over Luzon during the weekend.