Special Weather Statement - Moderate | Effective 05/23/2026 23:50

A tropical disturbance, known as JTWC's Invest 99W, is currently centered near 6N142E, just west of Eauripik. Although 99W remains broad and disorganized, convection has rapidly improved over the last day. Invest 99W is also connected to the monsoon trough to the south, bringing a fresh surge of westerly winds, which will allow it to organize. This convective structure is leading to a large area of numerous to widespread showers and isolated thunderstorms, and choppy seas across Chuuk and Yap State. Invest 99W remains rated sub-low by the JTWC, which means development into a significant tropical cyclone is not expected within the next few days. As Invest 99W lifts northward this week, a monsoon tail will intensify on the south side. Westerly to southwesterly winds of 20 to 30 kts will be possible along with seas hazardous to small craft. Guidance continues to show this region as a narrow band displaced from both Yap's and Palau's coastal waters, with seas remaining below 10 feet through Wednesday. As the system shifts further away, the monsoon tail may transition into an inflow tail with southerly flow. This could bring seas near hazardous conditions to Yap's coastal waters late this week. Residents and mariners should monitor the latest forecasts for the region at weather.gov/gum/PublicForecasts and any information shared by WSO Palau, WSO Yap, and WSO Chuuk for the local regions. For more information on Invest 99W, see bulletins issued by JTWC under WMO header ABPW10 PGTW and WTPN21 PGTW.