Typhoon Ragasa moved over the South China Sea on Monday night.  At 11:00 p.m. EDT on Monday the center of Typhoon Ragasa was located at latitude 20.2°N and longitude 117.7°E which put the center about 300 miles (485 km) east-southeast of Hong Kong.  Ragasa was moving toward the west at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 930 mb.

Typhoon Ragasa went through an eyewall replacement cycle, but the eyewall replacement only weakened Ragasa slightly.  A new eye with a diameter of 30 miles (50 km) was at the center of Ragasa’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Typhoon Ragasa.  Storms near the center of Ragasa generated strong upper level divergence that pumped mass away in all directions from the typhoon.  The removal of large quantities of mass in the upper levels was slightly less than the inflow of mass in the lower levels of the atmosphere.  The inflow of mass in the lower levels caused the surface pressure to increase slowly.

The circulation around Typhoon Ragasa was large.  Winds to typhoon force extended out 80 miles (130 km) from the center of Ragasa’s circulation.  Winds to tropical storm force extended out 240 miles (390 km) from the center of Typhoon Ragasa.

The Hurricane Intensity Index (HII) for Typhoon Ragasa was 29.9.  The Hurricane Size Index (HSI) was 28.7 and the Hurricane Wind Intensity Size Index (HWISI) was 58.6.  Typhoon Ragasa was larger and stronger than Hurricane Helene was when Helene hit Florida in 2024.

Typhoon Ragasa will move through an environment that will be favorable for a powerful typhoon during the next 24 hours.  Ragasa will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over China.  The upper level ridge will produce easterly winds that will blow toward the top of Ragasa’s circulation.  Those winds will cause the vertical wind shear to increase.  Typhoon Ragasa could weaken slowly during the next 24 hours because of more vertical wind shear.

Typhoon Ragasa will move around the southern side of a high pressure system over China.  The high pressure system will steer Ragasa toward the west-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Ragasa will be just south of Hong Kong in less than 24 hours.

Typhoon Ragasa will bring strong winds and locally heavy rain to coastal regions in southern China including Hong Kong.  Heavy rain is likely to cause flash floods in some locations.  Typhoon Ragasa could also cause a storm surge of up to 13 feet (4 meters) along parts of the coast.

Elsewhere over the Western North Pacific Ocean, Typhoon Neoguri moved farther east of Japan.  At 11:00 p.m. EDT on Monday the center of Typhoon Neoguri was located at latitude 30.6°N and longitude 153.3°E which put the center about 910 miles (1470 km) east of Tokyo, Japan.  Neoguri was moving toward the east-northeast at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 963 mb.