Guam, Northern Mariana Islands Coastal Flood Warning | Effective 04/14/2026 17:14

* WHAT...For the Coastal Flood Warning, significant coastal flooding, up to 10 feet for Tinian and Saipan; 6 feet for Rota, and up to 4 feet for Guam. For the High Surf Warning, dangerously large breaking waves of 11 to 16 feet for Guam, 15 to 20 feet for Rota, and 20 to 30 feet for Tinian and Saipan. * WHERE...North, east, south, and west facing reefs of Tinian and Saipan. South, west, and north facing reefs of Guam and Rota. * WHEN...For the Coastal Flood Warning, until 5 AM ChST Thursday. For the High Surf Warning, until 6 PM ChST Thursday. * IMPACTS...Numerous roads may be closed. Low lying property including homes, businesses, and some critical infrastructure will be inundated. Some shoreline erosion will occur. Breaking waves can sweep people off jetties and docks, and into dangerous seas. Life- threatening swimming conditions and significant beach erosion can be expected. * ADDITIONAL DETAILS...As TY Sinlaku moves away and wind driven waves decrease, the primary swell and highest surf will shift toward the northwest. The Coastal Flood Warning may need to be extended for Tinian and Saipan if Sinlaku slows down a bit.