Tropical Storm Wutip (01W) - Tropical Cyclone Advisory #6, 1200 UTC 6/12/25

…Wutip strengthens some more as it crawls toward Hainan Island… …Heavy rainfall occurring over portions of central Vietnam…

Current storm information:

• Position: 17.5°N 109.5°E

• Movement: WNW at 5 knots (10 km/h)

• Intensity [1-min]: 50 knots (95 km/h)

• Intensity [10-min]: 45 knots (85 km/h)

• Central pressure: 986 hPa

Trend:

• Some slight strengthening is possible before Wutip’s center moves over Hainan Island, with little change in strength expected thereafter.

Watches and warnings:

• The No. 3 storm signal is active for Macau for the possibility of near-gale winds.

• The No. 1 standby signal is active for Hong Kong.

Hazards affecting land:

• Wutip is currently producing torrential rainfall over portions of central Vietnam and southern Laos. This rainfall will spread over Hainan Island and southern China during the 12 to 24 hours, before shifting to southeastern China, Macau, and Hong Kong beginning on Saturday. Since Wutip will be relatively slow-moving, this rainfall is likely to cause widespread severe flooding. For further information, including possible warnings, refer to products from your local weather office.

Discussion:

Wutip continues to gradually get better organized as it crawls west-northwestward to the south of Hainan Island. The tropical storm remains vertically tilted from east to west due to the effects of moderate east-northeasterly shear associated with an upper-level trough positioned over the system. However, the convection continues to be quite intense with discrete bands present on microwave satellite imagery, suggesting that Wutip’s mid-level circulation is quite robust. A partial eye feature has been intermittently visible on that microwave imagery, but is currently not present. The low-level circulation is still partially exposed but is gradually tucking itself under the northeastern edge of the convection. The current intensity of 50 kts is based on ASCAT scatterometer data and a blend of T3.0 to T3.5 Dvorak fixes from PGTW, KNES, and RJTD, which is ahead of most of the automated estimates.

Wutip remains embedded in an area of weak steering currents as a result of being situated underneath the aforementioned upper-level trough. This trough is gradually lifting out of the area, which should encourage Wutip to gradually turn northward, then northeastward during the next couple of days. The shear currently affecting it is forecast to relax, but it does not seem that there will be enough time for Wutip to take advantage of a more favorable environment before making landfall on Hainan Island on Friday morning. Interaction with land will likely disrupt Wutip enough that it will likely change little in strength as it passes over the Gulf of Tonkin on Friday evening and Saturday morning. Wutip is forecast to make landfall on the western Leizhou Peninsula on Saturday evening. Shortly after landfall, Wutip will begin interacting with a frontal boundary over southern China, and this interaction will likely enable it to retain tropical storm-equivalent strength well inland. Wutip should become a post-tropical cyclone on Sunday before dissipating outright soon after.

Forecast positions and maximum winds

• 00 hrs: 17.5°N 109.5°E - 50 kts

• 12 hrs: 18.4°N 108.9°E - 50 kts on the southern coast of Hainan

• 24 hrs: 19.4°N 108.8°E - 50 kts on the northern coast of Hainan

• 48 hrs: 22.1°N 110.3°E - 40 kts inland

• 72 hrs: 25.6°N 114.6°E - 35 kts Post-tropical/extratropical

• 96 hrs: Dissipated