Tag Archives: Tongatapu

Tropical Cyclone Harold Brings Wind and Rain to Tonga

Tropical Cyclone Harold brought wind and rain to Tonga on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Harold was located at latitude 23.8°S and longitude 172.1°W which put it about 250 miles (400 km) southeast of Nuku Alofa, Tonga.  Harold was moving toward the east-southeast at 30 m.p.h. (50 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 945 mb.

After forming near the Solomon Islands and causing damage in Vanuatu and Fiji, Tropical Cyclone Harold brought gusty winds and locally heavy rain to portions of Tonga on Wednesday.  The core of Harold with the strongest winds passed about 60 miles (95 km)  southwest of Tongatapu.  However, winds to hurricane/typhoon force extended out 60 miles (95 km) from the center of Tropical Cyclone Harold.  Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation.  An airport at Fua’amotu, Tonga reported a sustained wind speed of 58 m.p.h. (93 km/h) when Harold passed southwest of its location.  The airport also reported a wind gust of 89 m.p.h. (143 km/h).

Tropical Cyclone Harold moved quickly away from Tonga on Wednesday night.  Weather conditions were improving.  A high pressure system over the South Pacific Ocean will continue to steer Harold rapidly toward the east-southeast during the next several days.  On its anticipated track Tropical Cyclone Harold will pass well to the south of Niue.

Tropical Cyclone Harold will move into a less favorable environment.  Harold will move under the southwestern part of an upper level ridge over the South Pacific Ocean.  The ridge will produce northwesterly winds which will blow toward the top of the circulation.  Those winds will cause moderate vertical wind shear.  Harold will also move over cooler water.  Moderate vertical wind shear and cooler water will cause Tropical Cyclone Harold to weaken.  Harold could eventually make a transition to an extratropical cyclone when it moves out of the tropics.

Tropical Cyclone Tino Speeds Across Tonga

Tropical Cyclone Tino sped quickly across Tonga on Saturday.  The core of Tino passed northeast of Nuku Alofa and the most populated island of Tonga.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Tino was located at latitude 24.0°S and longitude 170.6°E which put it about 370 miles (595 km) east-southeast of Nuku Alofa, Tonga.  Tino was moving toward the southeast at 26 m.p.h. (42 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 970 mb.

The strongest part of Tropical Cyclone Tino passed northeast of the more populated Tongatapu Group of islands in Tonga.  The core of Tino passed closer to the Vava’u Group and Ha’apai Group of islands in Tonga.  Winds to tropical storm force extended out 350 miles (565 km) from the center of Tino.  Tropical Cyclone Tino brought gusty winds and heavy rain to parts of Tonga.

Tropical Cyclone Tino began to weaken after it passed across Tonga.  Tino moved over water where the Sea Surface Temperature was cooler than 26°C.  Tropical Cyclone Tino moved southwest of an upper level ridge over the South Pacific Ocean.  The ridge caused moderate vertical wind shear and the wind shear contributed to the weakening of Tino.  Colder Sea Surface Temperatures and moderate vertical wind shear will cause Tropical Cyclone Tino to make a transition to an extratropical cyclone during the next two days.