Typhoon Goni Rapidly Intensifies Into Equivalent of Cat. 5 Hurricane

Typhoon Goni intensified rapidly into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale east of the Philippines on Thursday night. At 5:00 a.m. EDT on Friday the center of Typhoon Goni was located at latitude 16.2°N and longitude 131.2°E which put it about 620 miles (1000 km) east of Luzon. Goni was moving toward the west at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 205 m.p.h. (330 km/h). The minimum surface pressure was 912 mb. Typhoon Goni is capable of causing catastrophic damage.

Typhoon Goni continued to intensify rapidly on Thursday night. A small circular eye with a diameter of 10 miles (16 km) was at the center of Goni. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the tight core of Typhoon Goni. Storms near the core generated strong upper level divergence which pumped mass away from the typhoon. The removal of mass allowed the surface pressure to decrease quickly which contributed to the rapid increase in wind speed.

Typhoon Goni will move through an environment favorable for a strong typhoon during the next 36 to 48 hours. Goni will move over water where the Sea Surface Temperature is near 30°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could occur. The cycle would cause Goni to weaken when the original inner eyewall dissipates and convergence becomes concentrated into a new outer eyewall. An eyewall replacement cycle would also cause the size of the circulation around Goni to Increase.

Typhoon Goni will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Goni toward the west. On its anticipated track Typhoon Goni will approach the coast of Luzon in about 48 hours. Goni is likely to be the equivalent of a major hurricane when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Atsani moved south of the Marianas. At 5:00 a.m. EDT on Friday the center of Tropical Storm Atsani was located at latitude 11.6°N and longitude 142.6°E which put it about 170 miles (275 km) south-southwest of Guam. Astani was moving toward the west-northwest at 30 m.p.h. (48 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1001 mb. Tropical Storm Atsani was forecast to move toward the northwest and to strengthen.