Typhoon Ragasa (24W/Nando) – Tropical Cyclone Advisory #7: 1200 UTC 20 September 2025

…Ragasa explosively intensifies into a Category 3 typhoon… …Wind signals hoisted for parts of the Philippines…

Current storm information:

• Position: 17.3°N 128.6°E

• Movement: NW at 6 knots (10 km/h)

• Intensity: 100 knots (185 km/h) [Category 3] 

• Central pressure: 954 hPa

Trend:

• Additional rapid intensification is expected during the next 24 hours and Ragasa is expected to become a Category 4 typhoon later tonight. Ragasa could potentially become a Category 5 super typhoon on Monday.

Discussion:

The much-anticipated rapid intensification phase is well underway, and Ragasa’s structure has dramatically improved in a matter of hours. Although Ragasa is a very large typhoon, which would normally preclude an extremely high rate of strengthening, it has developed a very tight and compact inner core with a very small eye surrounded by a ragged central dense overcast. Microwave satellite imagery suggests that Ragasa may have concentric eyewalls, although this is difficult to determine for certain. The intensity is increased to 100 kts, based on consensus T5.5 Dvorak fixes, and lies between CIMSS ADT and D-PRINT estimates of 97 and 105 kts, making Ragasa a Category 3 typhoon on the Saffir-Simpson Hurricane Wind Scale.

The track forecast is unchanged from the previous one since the models continue to be consistent with a west-northwestward track through the Luzon Strait. Meanwhile, rapid intensification guidance continues to suggest high probabilities of extreme levels of intensification, with RIPA indicating a 53% chance of a 55 kt increase in the next 36 hours. Meanwhile, the HAFS-A model has backed off somewhat, but still shows significant intensification. The current forecast brings Ragasa to super typhoon intensity by Sunday evening, and it could reach Category 5 intensity on Monday before it enters the Luzon Strait. This is all dependent on inner core dynamics and potential eyewall replacement cycles. By Tuesday, Ragasa should turn toward the west as it gets captured by a ridge over China and interacts with an early season gap wind event in the Taiwan Strait. Increasing shear should also cause a more profound weakening trend, although Ragasa is likely to still be an intense typhoon as it passes south of Hong Kong and Macau on Wednesday and makes landfall on the Leizhou Peninsula on Thursday.

The current forecast track will likely result in potentially catastrophic typhoon conditions in the Batanes and Babuyan Islands on Monday. In addition, tropical storm conditions are likely along the northern coast of mainland Luzon and the southern coast of Taiwan. Higher elevations on Taiwan could see typhoon force winds. It is imperative that preparations to protect life and property be rushed to completion.

Forecast positions and maximum winds

• 00 hrs: 17.3°N 128.6°E – 100 kts

• 12 hrs: 18.0°N 127.4°E – 120 kts

• 24 hrs: 18.8°N 125.7°E – 140 kts

• 48 hrs: 20.0°N 121.5°E – 140 kts

• 72 hrs: 21.1°N 116.7°E – 120 kts

• 96 hrs: 21.3°N 112.1°E – 90 kts

• 120 hrs: 20.6°N 107.7°E – 65 kts