Tag Archives: Tropical Depression 20W

Tropical Storm Jebi Forms West of the Northern Marianas

Tropical Storm Jebi formed west of the Northern Marianas on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Jebi was located at latitude 18.7°N and longitude 144.6°E which put the center about 60 miles (95 km) west-northwest of Agrihan. Jebi was moving toward the north-northwest at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 45 m.p.h. (65 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1001 mb.

A low pressure system west of the Northern Marianas strengthened on Friday and the Japan Meteorological Agency designated the system as Tropical Storm Jebi.  The circulation around Tropical Storm Jebi was poorly organized.  Thunderstorms were occurring in the southeastern quadrant of Jebi’s circulation.  There were no thunderstorms near the center of Tropical Storm Jebi.  Bands in the other parts of Jebi’s circulation consisted primarily of showers and lower clouds.

Tropical Storm Jebi will move through an environment somewhat favorable for intensification during the next 24 hours.  Jebi will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southeastern part of an upper level ridge south of Japan.  The upper level ridge will produce northeasterly winds that will blow toward the top of Jebi’s circulation.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification.  Tropical Storm Jebi could intensify a little during the next 24 hours, if the wind shear does not get any stronger.

Tropical Storm Jebi will move around the western side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Jebi toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Jebi will move slowly away from the Northern Marianas.  Jebi could approach Iwo To in 36 hours.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 20W formed south-southeast of Taiwan.  At 11:00 a.m. EDT on Friday the center of Tropical Depression 20W was located at latitude 19.6°N and longitude 125.8°E which put the center about 430 miles (690 km) south-southeast of Taipei, Taiwan.  The tropical depression was moving toward the southwest 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 1001 mb.

Tropical Depression 20W Forms Southeast of Guam

Tropical Depression Twenty-W formed southeast of Guam on Wednesday. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Twenty-W was located at latitude 11.5°N and longitude 148.1°E which put it about 305 miles (490 km) east-southeast of Guam. The tropical depression moving toward the west-northwest at 10 m.p.h. (16 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). T he minimum surface pressure was 1005 mb.

Tropical Depression Twenty-W developed over the Western North Pacific Ocean southeast of Guam on Wednesday. The circulation around the tropical depression was organizing quickly. Thunderstorms formed near the center of the tropical depression. Other thunderstorms developed in bands revolving around the center of circulation. Storms near the center began to generate upper level divergence that pumped mass away from the depression.

Tropical Depression Twenty-W will move through an environment favorable for intensification during the next few days. The tropical depression will move over water where the Sea Surface Temperatures are near 30˚C. It will move into a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Depression Twenty-W could strengthen to a tropical storm during the next 12 hours. It could intensify more rapidly after an inner core becomes more well developed. It could intensify to a typhoon within 36 hours.

Tropical Depression Twenty-W will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean during the next several days. The high will steer the tropical depression toward the northwest during the next 36 hours. On its anticipated track the tropical depression could reach the Marianas in less than 24 hours. Tropical Depression Twenty-W could intensify to a tropical storm before it reaches the Marianas. It will bring gusty winds and locally heavy rain to the Marianas including Guam.

Elsewhere over the Western North Pacific Ocean, Tropical Depression Twentyone-W formed over the South China Sea east of Vietnam. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Twentyone-W was located at latitude 12.9°N and longitude 112.8°E which put it about 400 miles (605 km) east-southeast of Da Nang, Vietnam. The tropical depression moving toward the west-northwest at 13 m.p.h. (20 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). T he minimum surface pressure was 1005 mb. Tropical Depression Twentyone-W is forecast to move toward the west-northwest and to strengthen to a tropical storm. It could reach the coast of Vietnam south of Da Nang in about 24 hours.