Tropical Storm 06W – Tropical Cyclone Advisory #3: 0000 UTC 12 July 2025

…Depression strengthens into a tropical storm… …Still nearly stationary near Iwo Jima…

Current storm information:

• Position: 25.2°N 140.5°E

• Movement: Nearly stationary

• Intensity: 35 knots (65 km/h)

• Central pressure: 1002 hPa

Trend:

• Some strengthening is forecast during the next 24 hours.

Watches and warnings:

• There are no land-based watches or warnings in effect.

Hazards affecting land:

• Interests along the eastern coast of Honshu and in the Aleutian Islands should monitor the progress of this system.

Discussion:

06W remains a sheared system. The system continues to consist of a partially exposed but well defined low level circulation center displaced well to the north and west of a large area of intense convection. Despite the system clearly not being vertically aligned, its mid-level circulation is quite robust as it continues to produce strong and well organized convection. Dvorak fixes are a consensus T2.5, and CIMSS ADT and AiDT estimates of 34 and 32 kts suggest 06W has strengthened into a tropical storm, and the intensity is increased to 35 kts.

TS 06W is continuing to move very little due to weak steering currents. A very strong subtropical ridge is forecast to build in to the northeast, and this will cause 06W to begin accelerating northward at a very quick rate during the next couple of days. Some strengthening is possible while 06W remains over warm waters, and 06W will likely reach peak intensity in about 36 hours or so. By Monday, 06W will quickly move over cooler waters and interact with a frontal system approaching from the west as it passes just off the east coast of Honshu. These conditions should cause 06W to rapidly lose tropical characteristics and become post-tropical near or over Hokkaido by Tuesday. Global model guidance suggests that 06W will remain a distinct entity through the end of the 5-day forecast period, and the forecast maintains 06W as a gale-force extratropical low through the end of the period.

Forecast positions and maximum winds

• 00 hrs: 25.2°N 140.5°E – 35 kts

• 12 hrs: 25.4°N 140.9°E – 40 kts

• 24 hrs: 26.8°N 141.7°E – 45 kts

• 48 hrs: 33.5°N 140.5°E – 55 kts

• 72 hrs: 44.5°N 143.6°E – 45 kts Post-tropical/extratropical

• 96 hrs: 48.5°N 162.5°E – 35 kts Post-tropical/extratropical

• 120 hrs: 51.5°N 179.5°W – 35 kts Post-tropical/extratropical