Typhoon Halong (28W) – Tropical Cyclone Advisory #12: 0000 UTC 10 October 2025

Halong forecast to take a journey into the Arctic as a post-tropical cyclone.

Author

Will Weaver
October 09, 2025

…Halong forecast to take a journey into the Arctic as a post-tropical cyclone…

Himawari-9 visible satellite image (Weathernerds)

Current storm information:

  • Position: 34.4°N 154.8°E

  • Movement: E at 30 knots (55 km/h)

  • Intensity: 65 knots (155 km/h) [Category 1]

  • Central pressure: 975 hPa

Trend:

  • Little change in strength is forecast during the next 24 hours, and Halong should become a post-tropical cyclone later today.

Watches and warnings:

  • There are no coastal watches or warnings in effect.

Hazards affecting land:

  • Interests in the Aleutian Islands and mainland Alaska should monitor the progress of Halong. Halong’s post-tropical remnants could produce storm- to hurricane-force winds and heavy rain or snow over portions of western Alaska early next week. For additional information, refer to products from the U.S. National Weather Service.

Discussion:

Himawari-9 infrared satellite image (Weathernerds)

Halong is just about extratropical. The typhoon has continued to take on a non-tropical satellite presentation with well-defined warm and cold fronts very close to its center. Most of the convection is displaced well to the northeast of the center along a frontal boundary, although the center stubbornly continues to generate deep convection. This convection is enough for KNES, RJTD, and PGTW to classify Halong with the Dvorak technique, and so it remains a 65 kt typhoon at this time.

Halong has crossed the threshold of 26°C SSTs and is now moving over colder waters, and this should very shortly put an end to its efforts to generate convection. Halong should become post-tropical later today. The post-tropical cyclone should turn northeastward and accelerate as it interacts with a deep low pressure area in the western Bering Sea. As it does, it should explosively deepen to around 940 hPa as it passes between Russia and Alaska. The post-tropical cyclone is expected to remain a distinct entity even at the end of the forecast period, when it will be wandering in the Arctic Ocean as a component of the polar vortex.

Forecast positions and maximum winds

  • 000 hrs: 34.4°N 154.8°E – 65 kts

  • 012 hrs: 34.6°N 162.4°E – 60 kts Post-tropical/extratropical

  • 024 hrs: 37.4°N 171.1°E – 55 kts Post-tropical/extratropical

  • 048 hrs: 49.4°N 174.0°W – 55 kts Post-tropical/extratropical

  • 072 hrs: 61.7°N 172.0°W – 65 kts Post-tropical/extratropical

  • 096 hrs: 68.1°N 164.5°W – 55 kts Post-tropical/extratropical inland over Alaska

  • 120 hrs: 76.0°N 147.0°W – 30 kts Post-tropical/extratropical over Arctic Ocean

JMA forecast map. Extratropical phase omitted.