Moderate Special Weather Statement | Effective 09/23/2026 00:01

Invest 91W remains under a Tropical Cyclone Formation Alert from the Joint Typhoon Warning Center, meaning development into a significant tropical cyclone is expected to occur in the next 24 hours. As Invest 91W lifts to the northwest and away from the region, conditions will slowly improve through late this week. Monsoonal inflow into 91W that has brought heavy rainfall, gusty winds, and locally choppy seas to portions of Yap State the last couple of days will also lift northward as Invest 91W moves away from the region. That being said, locally heavy showers will still be possible through Thursday with occasional gusts to around 25 mph also possible, especially near heavier showers and thunderstorms. This will be the last issuance of this product for this event. Residents should continue to monitor forecasts and be aware of the latest weather conditions and trends before traveling between islands. Stay up-to-date with all the latest forecasts at weather.gov/gum and by following the latest information from your local Weather Service Office.