Post-Tropical Cyclone Sinlaku (04W) – Tropical Cyclone Advisory #23 (FINAL): 1500 UTC 19 April 2026

Sinlaku becomes a post-tropical cyclone over the cold waters of the west central Pacific. This is the last advisory.

Author

Will Weaver
April 19, 2026

…Sinlaku becomes a post-tropical cyclone over the cold waters of the west central Pacific…
…This is the last advisory…

Himawari-9 infrared satellite image (Weathernerds)

Current storm information:

  • Position: 28.6°N 154.9°E

  • Movement: ENE at 21 knots (35 km/h)

  • Intensity: 55 knots (100 km/h)

  • Central pressure: 984 hPa

Trend:

  • Little change in strength is forecast during the next 24 hours.

Watches and warnings:

  • There are no coastal watches or warnings in effect.

Areas that should monitor this system:

  • None.

Hazards affecting land:

  • None.

Discussion:

Sinlaku is rapidly completing extratropical transition. The system has not had central deep convection for almost 36 hours, and the convection that remains is beginning to take on an extratropical comma-like structure. Water vapor satellite imagery indicates that warm and cold fronts are developing, and Sentinel-1 SAR and ASCAT data indicate that the wind field has broadened to the north and northeast along the developing warm front. These wind data also suggest the cyclone is producing winds of 50 to 55 kts, so the intensity is increased to 55 kts, and Sinlaku is now a post-tropical cyclone.

The post-tropical cyclone is forecast to maintain storm-force winds for another day or so before it shears apart as it approaches the Date Line and interacts with a frontal system to the north.

This is the last advisory on Sinlaku.

Forecast positions and maximum winds (1-min)

  • 000 hrs: 28.6°N 154.9°E – 55 kts 100 km/h POST-TROPICAL/EXTRATROPICAL

  • 012 hrs: 29.4°N 158.6°E – 50 kts 95 km/h POST-TROPICAL/EXTRATROPICAL

  • 024 hrs: 30.0°N 164.0°E – 50 kts 95 km/h POST-TROPICAL/EXTRATROPICAL

  • 048 hrs: DISSIPATED

JTWC forecast map