Severe · Special Marine WarningThis alert has expired. It is kept for reference.

Special Marine Warning issued October 18 at 7:03PM ChST until October 18

Affecting Guam Coastal Waters

In effect until: Oct 18, 2026, 9:30 AM

Guam Coastal Waters

Likely impact; effects through 9:30 AM.

WATERSPOUTS CAN EASILY OVERTURN BOATS AND CREATE LOCALLY HAZARDOUS SEAS. SEEK SAFE HARBOR IMMEDIATELY.

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SMWGUM

THE NATIONAL WEATHER SERVICE IN TIYAN GUAM HAS ISSUED A

* SPECIAL MARINE WARNING FOR...
GUAM COASTAL WATERS...

* UNTIL 730 PM CHST.

* AT 703 PM CHST...A SHOWER CAPABLE OF PRODUCING WATERSPOUTS WAS
LOCATED OVER EASTERN GUAM WATERS MOVING NORTH AT 30 KNOTS.

HAZARD...WATERSPOUTS AND WIND GUSTS 34 KNOTS OR GREATER.

SOURCE...RADAR.

IMPACT...WATERSPOUTS CAN CREATE LOCALLY HAZARDOUS SEAS. SMALL

CRAFT COULD BE DAMAGED IN BRIEFLY HIGHER WINDS AND

SUDDENLY HIGHER WAVES.

* THE SHOWER WILL REMAIN OVER MAINLY OPEN WATERS.

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Alert data: U.S. National Weather Service / NOAA · Translation: WeatherTranslate™

Special Marine Warning issued October 18 at 7:03PM ChST until October 18

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