Super Typhoon Ragasa (24W/Nando) – Tropical Cyclone Advisory #10: 0000 UTC 22 September 2025

Potentially catastrophic Category 5 Ragasa bearing down on the Babuyan Islands. This is a particularly dangerous situation!

Author

Will Weaver
September 21, 2025

…Potentially catastrophic Category 5 Ragasa bearing down on the Babuyan Islands… …This is a particularly dangerous situation…

Himawari-9 visible satellite image (Weathernerds)

Current storm information:

  • Position: 19.4°N 123.0°E

  • Movement: W at 12 knots (25 km/h)

  • Intensity: 145 knots (270 km/h) [Category 5] 

  • Central pressure: 906 hPa

Trend:

  • Fluctuations in intensity are possible during the next 24 hours. However, Ragasa is expected to remain a super typhoon during that time.

Watches and warnings:

PAGASA wind signal map (click to enlarge)

  • Typhoon warning (Taiwan): Kaohsiung City, Pingtung County, Taitung County

  • TCWS #5 (Philippines): All of the Babuyan Islands EXCEPT for Fuga Island

  • TCWS #4 (Philippines): Batan and Sabtang in the Batanes Islands, Fuga Island in the Babuyan Islands, far northern Ilocos Norte, far northwestern and far northeastern Cagayan

  • TCWS #3 (Philippines): Itbayat in the Batanes Islands, the rest of Ilocos Norte, northern Apayao, northern and central Cagayan

  • TCWS #2 (Philippines): Ilocos Sur, Abra, southern Apayao, Kalinga, Mountain Province, Isabela, northern La Union, northern Benguet, far northeastern Nueva Vizcaya

  • TCWS #1 (Philippines): The remainder of northern Luzon from Manila Bay northward

Hazards affecting land:

  • Typhoon conditions - destructive winds and heavy rainfall that could cause life-threatening flooding - are expected on the Batanes and Babuyan Islands on Monday. In addition, tropical storm conditions are possible along the southern coast of Taiwan and along the northern coast of mainland Luzon. All necessary preparations to protect life and property should have been completed by now.

  • Tropical storm conditions and extremely heavy rainfall are expected in portions of southern Taiwan, mainly near the central mountain range. Rainfall amounts of up to 500 mm are possible through Tuesday evening, and this rain could cause life-threatening flash flooding and landslides.

  • Monsoonal rainfall enhanced by Ragasa’s outflow could produce areas of heavy rainfall over portions of Luzon beginning during the next few hours and continuing through Tuesday. Storm total rainfall of up to 200 mm is possible through Tuesday evening.

  • Interests in southern China, including Hong Kong and Macau, should also closely monitor the progress of this system. It is possible that Ragasa will still be a very intense typhoon by the time it approaches that area on Wednesday.

Discussion:

Himawari-9 visible image of Ragasa’s eye, showing the mesovortices within (Weathernerds)

Ragasa has completed its eyewall replacement cycle, and it is now an extremely picturesque tropical cyclone as it begins to enter the Luzon Strait. Ragasa consists of a symmetrical central dense overcast with very cold convective cloud tops, although cloud tops north of the eye have warmed slightly in the last few hours. The eye is well-defined and very large and warm, with numerous mesovortices evident on visible satellite imagery. The eye is currently wobbling westward and is about to pass directly over the northern Babuyan Islands, with a direct passage over Babuyan and Calayan likely during the next few hours. Microwave satellite imagery indicates that there is still a concentric eyewall structure, which means another eyewall replacement cycle could be imminent. Dvorak fixes range from T7.0 to T7.5 while CIMSS ADT, D-PRINT, and SATCON estimates range from 137 to 154 kts; taking an average of these estimates results in an intensity of 145 kts.

F-17 SSMIS 91GHz microwave satellite image (CIRA)

Ragasa now appears to be moving due west, and the ridge to the north is holding serve, so the forecast track has been nudged to the south of the previous one. On this track, Ragasa is expected to pass over the Babuyan Islands during the next few hours, and the eyewall could get close enough to coastal northern Luzon to produce typhoon conditions there. Meanwhile, it seems unlikely that there will be enough land interaction to negatively impact Ragasa’s structure, so its intensity will be governed more by inner core dynamics and potential eyewall replacement cycles during the next 24 hours. Given the favorable environment, some additional strengthening cannot be ruled out.

Ragasa should enter the South China Sea on Tuesday, and this will correspond with an increase in shear and a decrease in oceanic heat content, which will likely begin a gradual weakening trend. Ragasa is likely to remain an intense typhoon during this time, and it is likely to make a very close approach to Hong Kong and Macau on Wednesday. Landfall near those areas cannot be ruled out as the HAFS-A and some GFS and ECMWF ensemble members show an intense typhoon landfall. Whether it does or not, Ragasa is likely to turn west-southwestward late in the week and weaken more rapidly, passing over the Leizhou Peninsula early Thursday and making a final landfall in northern Vietnam on Friday. Ragasa will likely dissipate over Laos by the end of the forecast period.

Forecast positions and maximum winds

  • 00 hrs: 19.4°N 123.0°E – 145 kts

  • 12 hrs: 19.6°N 120.6°E – 150 kts

  • 24 hrs: 20.1°N 118.3°E – 140 kts

  • 48 hrs: 21.1°N 113.7°E – 120 kts

  • 72 hrs: 21.1°N 108.6°E – 60 kts

  • 96 hrs: 20.7°N 102.0°E – 25 kts inland

  • 120 hrs: Dissipated

JMA forecast map