Severe Tropical Storm Bualoi (26W/Opong) – Tropical Cyclone Advisory #5: 1200 UTC 25 September 2025

Bualoi to make landfall in northern Samar within the next few hours.

Author

Will Weaver
September 25, 2025

…Bualoi to make landfall in northern Samar within the next few hours…

Himawari-9 infrared satellite image (Weathernerds)

Current storm information:

  • Position: 11.7°N 126.9°E

  • Movement: WNW at 15 knots (25 km/h)

  • Intensity: 55 knots (100 km/h)

  • Central pressure: 992 hPa

Trend:

  • Some additional weakening is forecast during the next 24 hours.

Watches and warnings:

PAGASA wind signal map (click to enlarge)

  • TCWS #3 (Philippines): Southern and central Albay, Burias Island, Sorsogan, Ticao Island, Masbate, Northern Samar, northern Samar, northern Eastern Samar

  • TCWS #2 (Philippines): Laguna, Lubang Island, Batangas, Quezon, Occidental Mindoro, Oriental Mindoro, Calamian Islands, Marinduque, Camarines Norte, Camarines Sur, northern Albay, Catanduanes, Romblon, northern Aklan, northern Capiz, northern Cebu, Biliran, northern Leyte, southern Samar, southern Eastern Samar

  • TCWS #1 (Philippines): A large swath of the Philippines, including Metro Manila, is under TCWS #1. The area ranges from Ifugao southward to Surigao del Norte. It’s too long to list, refer to the attached graphic for details.

Hazards affecting land:

  • Bualoi is likely to produce strong, damaging winds and heavy rainfall over portions of the Eastern and Central Visayas beginning early Friday morning. These conditions will likely spread across the western Bicol Region, Mindoro, and Metro Manila on Friday evening. Storm total rainfall of up to 200 mm is possible within these areas through Saturday, with rainfall of up to 100 mm possible over portions of central Luzon and northern Mindanao. This rainfall could cause flooding of low-lying areas. For additional information, refer to products from your local weather office.

  • Interests in Hainan Island and northern Vietnam should monitor the progress of Bualoi.

Discussion:

GPM GMI 37GHz microwave satellite image

Bualoi continues to experience the effects of strong northeasterly shear tonight. The tropical storm is currently exhibiting a central cold cover (CCC) pattern, which is common in strongly sheared tropical cyclones and is not an indication of strengthening. This shear is being produced by a small upper-level anticyclone positioned to the north, off the eastern coast of Luzon. The convection remains quite intense, with cloud tops as cold as -85°C, and the surface circulation center is tucked just under the eastern edge of the convective mass. Microwave satellite imagery indicates that the mid-level structure that had been present before has collapsed, and there are no longer indications of an eye feature present, although convection wrapping into the mid-level circulation center remains quite intense. JMA continues to insist that Bualoi is a typhoon, but none of the available estimates support typhoon strength, and in fact, it appears Bualoi has weakened. The intensity is lowered to 55 kts, based on consensus T3.5 Dvorak fixes and CIMSS ADT and D-PRINT estimates of 57 kts. A recent RCM-3 SAR pass only found winds of 49 kts in the southeastern semicircle, so this could be generous. This pass also indicated that the low-level circulation is quite elongated.

Bualoi is about 6 hours away from making landfall on the island of Samar. The shear is forecast to persist for another day or so, so continued weakening appears likely up to and shortly after landfall. As Bualoi gains some latitude, it should begin to encounter less shear, and passage over water as it traverses the Visayas and Mindoro will likely slow its weakening trend. Bualoi should emerge over the South China Sea on Saturday. Conditions there should be much more conducive for strengthening, although Bualoi will only have a brief window of opportunity to do so as it gets swept up in strong easterly flow associated with a strong subtropical ridge to the north. Nonetheless, Bualoi will likely become a typhoon before it passes near or over Hainan Island late Sunday evening. Bualoi will likely make landfall in northern Vietnam on Monday evening, and the system should quickly decay into a trough of low pressure shortly after.

Forecast positions and maximum winds

  • 000 hrs: 11.7°N 126.9°E – 55 kts

  • 012 hrs: 12.5°N 123.9°E – 50 kts near Ticao Island

  • 024 hrs: 13.4°N 121.1°E – 45 kts inland over Mindoro

  • 048 hrs: 15.5°N 114.6°E – 55 kts

  • 072 hrs: 18.3°N 109.2°E – 65 kts

  • 096 hrs: 20.1°N 104.0°E – 50 kts inland

  • 120 hrs: 20.8°N 101.4°E – 25 kts inland

JMA forecast map