Typhoon Chanthu intensified to the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale east of northern Luzon on Wednesday. At 5:00 a.m. EDT on Wednesday the center of Typhoon Chanthu was located at latitude 15.5°N and longitude 130.8°E which put it about 630 miles (1015 km) east-southeast of Aparri, Philippines. Chanthu was moving toward the west-southwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 195 m.p.h. (315 km/h). The minimum surface pressure was 915 mb.

Typhoon Chanthu intensified to the equivalent of a Category 5 hurricane on Wednesday morning. A small eye was at the center of Typhoon Chanthu. 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 revolved around the core of Chanthu. Storms near the core generated strong upper level divergence that pumped mass away from the typhoon. The inner end of a rainband wrapped part of the way around the core of Typhoon Chanthu. Concentric eyewalls might be developing, which would indicate the start of an eyewall replacement cycle.

The circulation around Typhoon Chanthu was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Chanthu. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Chanthu was 35.0. The Hurricane Size Index (HSI) was 7.1 and the Hurricane Wind Intensity Size Index (HWISI) was 42.1. Typhoon Chanthu was capable of causing localized catastrophic damage.

Typhoon Chanthu will move through an environment capable of maintaining a strong typhoon during the next 48 hours. Chanthu 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 an eyewall replacement cycle occurs, Typhoon Chanthu will weaken when the inner eyewall weakens. An eyewall replacement cycle would increase the size of the circulation around Chanthu when the outer eyewall forms.

Typhoon Chanthu will move south of a high pressure system over the Western North Pacific Ocean. The high will steer Chanthu toward the west during the next several days. On its anticipated track Typhoon Chanthu could approach northeastern Luzon in 48 hours. Chanthu will likely still be a powerful typhoon when it approaches Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Conson continued to bring wind and rain to parts of Luzon. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Conson was located at latitude 14.3°N and longitude 120.5°E which put it about 35 miles (55 km) south-southwest of Manila, Philippines. Conson was moving toward the northwest at 8 m.p.h. (13 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 988 mb.