Super Typhoon Sinlaku (04W) – Tropical Cyclone Advisory #10: 0000 UTC 13 April 2026

Potentially catastrophic Category 5 Sinlaku strengthens a little more while moving northwestward toward the Marianas. This is a particularly dangerous situation!

Author

Will Weaver
April 12, 2026

…Potentially catastrophic Category 5 Sinlaku strengthens a little more while moving northwestward toward the Marianas…
…This is a particularly dangerous situation…

Himawari-9 visible satellite image (all conventional satellite imagery in this post is courtesy of Weathernerds)

Current storm information:

  • Position: 12.2°N 148.8°E

  • Movement: NW at 9 knots (15 km/h)

  • Intensity: 155 knots (285 km/h)

  • Intensity category: 5

  • Central pressure: 897 hPa

Trend:

  • Fluctuations in intensity are likely during the next 24 hours.

Watches and warnings:

  • Typhoon warning (NWS) - Rota, Tinian, and Saipan in the CNMI

  • Tropical storm warning (NWS) - Ulul in Chuuk State; Guam

  • Typhoon watch (NWS) - Ulul in Chuuk State; Guam

  • Tropical storm watch (NWS) - Pagan and Agrihan in the CNMI

  • TCCOR 2 - Guam

Areas that should monitor this system:

  • Chuuk State

  • Guam

  • Rota, Tinian, and Saipan in the CNMI

Hazards affecting land:

  • Conditions in Chuuk State should gradually improve during the next 12 hours.

  • Sinlaku is forecast to make a very close approach to Tinian and Saipan on Tuesday. Although Sinlaku is forecast to be at a slightly lower intensity by then, it is expected to remain at or near Category 5 intensity. Potentially catastrophic damaging winds and heavy rain are expected to begin late Monday night and could persist through Wednesday. This is an extremely dangerous and life-threatening situation! Preparations to protect life and property should be rushed to completion. Refer to products from your local weather office for further information.

  • Information for U.S. military interests can be found at the Stars & Stripes Pacific Storm Tracker, located here: https://www.stripes.com/theaters/asia_pacific/storm_tracker/

Discussion:

Sinlaku remains a textbook intense tropical cyclone. The typhoon continues to sport an impressive satellite presentation consisting of a nearly perfectly symmetric central dense overcast surrounding a large, clear, and warm eye with 22-23°C eye temperatures. Cloud tops within the central dense overcast have warmed slightly during the past few hours, however, and while the inner core remains very tight with a solid eyewall with very intense convection, there are indications on recent microwave satellite imagery that a concentric eyewall structure has developed with a moat of dry air separating the inner and outer eyewalls. This is a harbinger of an impending eyewall replacement cycle. For the time being, however, Sinlaku remains extremely intense, and a blend of T7.5 Dvorak estimates supports an intensity of 155 kts. It should be noted that automated estimates are higher, ranging from 155 to 164 kts, and the CIMSS D-MINT tool peaked at 168 kts, which is the highest it has measured.

GPM GMI 89GHz microwave satellite image

There are no major changes to the forecast. Sinlaku is forecast to continue moving generally northwestward, and while the rate of change of Sinlaku’s intensity will depend on whether an eyewall replacement occurs and how quickly it progresses, it should gradually move over slightly cooler SSTs that cannot support such an intense tropical cyclone. Thus, a slow weakening trend is forecast during the next couple of days. Sinlaku is expected to be at or near Category 5 strength as it makes its closest approach to Tinian and Saipan late Tuesday night into Wednesday. By Thursday, Sinlaku is forecast to turn northward into a weakness in the ridge and gradually recurve off to the northeast through the end of the forecast period. A faster rate of weakening is likely to begin around then as Sinlaku encounters strong southwesterly shear and much cooler SSTs, and Sinlaku may be well into extratropical transition by the end of the week.

Forecast positions and maximum winds (1-min)

  • 000 hrs: 12.2°N 148.8°E – 155 kts 285 km/h 

  • 012 hrs: 13.2°N 147.4°E – 155 kts 285 km/h 

  • 024 hrs: 14.3°N 146.0°E – 150 kts 280 km/h 

  • 048 hrs: 15.8°N 144.6°E – 135 kts 250 km/h 

  • 072 hrs: 18.1°N 143.1°E – 120 kts 220 km/h 

  • 096 hrs: 20.6°N 143.5°E – 95 kts 175 km/h 

  • 120 hrs: 23.3°N 144.5°E – 75 kts 140 km/h 

JMA forecast map