Post-Tropical Cyclone Ragasa (24W) – Tropical Cyclone Advisory #16 (FINAL): 0000 UTC 25 September 2025

Ragasa becomes a post-tropical cyclone over southern China. This is the last advisory.

Author

Will Weaver
September 24, 2025

…Ragasa becomes a post-tropical cyclone over southern China… …This is the last advisory…

Himawari-9 visible satellite image (Weathernerds)

Current storm information:

  • Position: 22.0°N 108.5°E

  • Movement: W at 11 knots (20 km/h)

  • Intensity: 45 knots (85 km/h) 

  • Central pressure: 992 hPa

Trend:

  • The post-tropical cyclone is forecast to continue weakening during the next day or so, and it will likely degenerate into a remnant low by tonight.

Watches and warnings:

  • There are no land-based watches or warnings in effect.

Hazards affecting land:

  • Heavy rain is expected to spread across portions of southern China and far northeastern Vietnam during the next couple of days. This heavy rainfall could result in widespread flooding. For additional information, refer to products from your local weather office.

Discussion:

Since the previous advisory, Ragasa’s convection has very quickly evaporated in a way you don’t typically see in this basin. Aside from one skeletal band of convection well to the west of the circulation center, there is no significant convection associated with Ragasa. Ragasa’s circulation has also broadened quite a bit during the past several hours, and it has become poorly defined. Ragasa is not forecast to move back over water, so it is unlikely convection will return. As a result, Ragasa is now a post-tropical cyclone. The intensity is lowered to a possibly generous 45 kts.

The post-tropical cyclone is forecast to continue weakening as it moves westward across far southern China and into northern Vietnam, and the circulation should spin down and become a remnant low by tonight. The system should decay into a trough of low pressure on Friday. As Ragasa passes close to the northern portion of the Gulf of Tonkin, it may be able to regenerate some convection, but it is unlikely to persist long enough for Ragasa to qualify as a tropical cyclone.

This is the last advisory on Ragasa.

Forecast positions and maximum winds

  • 00 hrs: 22.0°N 108.5°E – 45 kts Post-tropical inland

  • 12 hrs: 21.5°N 106.2°E – 30 kts Post-tropical/remnant low inland

  • 24 hrs: 21.3°N 105.4°E – 20 kts Post-tropical/remnant low inland

  • 48 hrs: DissipatedJ

JMA forecast map