Winds and Rain Expected for the Marianas; Small Craft Advisory in Effect this Evening

Winds and Rain Expected for the Marianas; Small Craft Advisory in Effect this Evening

The National Weather Service (NWS) Weather Forecast Office Guam continue to monitor a developing tropical depression well northeast of the Marianas that will cause monsoon winds and westerly swell to increase across the region for the next couple of days.
small craft advisory is in effect for Guam, Rota, Tinian, and Saipan coastal waters, from 6 p.m. this evening to 6 a.m. Monday. West winds of 19 to 24 mph today will become hazardous at 24 to 29 mph overnight. Southwest winds will increase further Saturday, peaking at 29 to 24 mph before gradually subsiding Sunday andSunday night. Seas of 5 to 6 feet today will increase overnight and become hazardous at 9 to 11 feet early Saturday morning. Larger seas are expected farther north where seas could reach up to around 13 feet Saturday afternoon and night.
Inexperienced mariners, especially those operating smaller vessels, should avoid sailing in these conditions.
A special weather statement remains in effect for Guam, Rota, Tinian, and Saipan. A monsoon surge associated with a tropical depression east-northeast of Alamagan, Commonwealth of the Northern Mariana Islands (CNMI), is producing widespread cloudiness and scattered showers across the Marianas. At 7 a.m., the tropical depression was located 525 miles northeast of Guam.
A tropical storm watch is now in effect for Pagan, Agrihan and Alamagan in the northern CNMI. There are no watches and warnings for Guam.
The monsoon surge is expected to strengthen Friday night and Saturday. For the Marianas, winds are expected to increase to 25 to 35 mph, with gusts to 45 mph in heavy showers Saturday and Saturday night.
In addition to the winds and seas, scattered showers and isolated thunderstorms are expected through Friday, with widespread locally heavy showers on Saturday. Rainfall of 3 to 6 inches is possible through Sunday.
Due to the expected winds and rain, it is advised to take basic precautionary actions now. To prepare for any scenario, residents and visitors are advised to:
  • Locate or prepare your emergency preparedness kits for your household
  • Clear loose debris around your yard and store any items, such as canopies, that may become airborne in heavy wind
  • Gas your vehicles and get fuel for your generators
  • Stay up to date in the event there additional advisories
Those living in areas prone to flooding should be prepared to take action should flooding develop. The following are basic flood safety tips to keep in mind:
  • Now is a good time to clear drainage areas and un-block clogged storm drains in your area to minimize the chance of flooding.
  • Avoid walking or driving through flood waters.
  • Just 6 inches of moving water can knock you down, and 2 feet of water can sweep your vehicle away.
  • If there is a chance of flash flooding, move immediately to higher ground.
  • If floodwaters rise around your car but the water is not moving, abandon the car and move to higher ground. Do not leave the car and enter moving water.
  • Avoid camping or parking along streams, rivers, and creeks during heavy rainfall. These areas can flood quickly and with little warning.
Visit to learn more.
The Offices of Guam Homeland Security and Civil Defense (GHS/OCD) remind all residents and visitors to practice extreme caution if traveling in these conditions in the coming days. Monitor the latest advisory information through the following sites, especially if outdoor or marine activities were planned:
For more information, contact GHS/OCD Public Information Officer, Jenna G. Blas at (671) 489-2540 or via email at


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June 2018 is Typhoon Preparedness Month