Hazardous seas, surf, and strong current advisories in effect through Thursday

The National Weather Service Weather Forecast Office Guam issued a hydrologic outlook for Guam, Rota, Tinian, and Saipan. A shear line is pushing southward near Guam and Rota, bringing showers, gusty winds and the potential for thunderstorms and locally heavy rainfall. 

Numerous to widespread showers could produce 2 to 4 inches of rainfall across the Marianas, with locally higher amounts accompanying any embedded thunderstorms, particularly for Guam and Rota tonight through Wednesday morning. Flash flooding remains a possibility.

Additionally, multiple marine-related advisories are in effect due to strong winds over the coastal waters, large swell and high surf. Seas and surf are expected to build through Wednesday. Hazardous surf of 9 feet or more could potentially build to as high as 15 feet by Wednesday. Rip currents will be life-threatening.

Residents and visitors are advised to take the following precautionary actions:

• Those living in flood-prone areas should take action; clear drainage areas and unblock storm drains to minimize flooding;
• Stay up to date with the latest weather information;
• When driving in heavy rain, be alert for low visibilities and slippery roads;
• Slow down where water is ponding on the road;
• Remain out of the water while advisories are in effect.

Advisories in Effect:

High Surf Advisory for Guam, Rota, Tinian, and Saipan (9–13 ft surf) until 5 p.m. Wednesday.

High Risk of Rip Currents for Guam, Rota, Tinian, and Saipan through Wednesday afternoon.

Hazardous Seas Watch for Guam, Rota, Tinian and Saipan coastal waters, through Thursday afternoon (seas 11-16 ft possible). 

Small Craft Advisory for Guam, Rota, Tinian, and Saipan coastal waters (winds 20–30 kt; seas 9–14 ft) until 5 a.m. Wednesday.