High Surf in Guam, September 22 to 23, 2015

Name: High Surf in Guam, September 22 to 23, 2015
Start: 2015-09-22T05:00
End: 2015-09-23T04:00
Location: Guam

September 22 to 23, 2015 · NWS GUM · 1 event in 1 county or zone

Swells from a tropical depression built up seas across the Marianas. The higher seas and swells caused the death of a swimmer.

The toll

Deaths: 1
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS GUM wrote it up.

Swells from a tropical depression built up seas across the Marianas. The higher seas and swells caused the death of a swimmer.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Guam wrote its last area forecast discussion before the first event at Sep 21, 5:57 AM UTC, 13 hours 3 minutes earlier.

Area forecast discussion, Sep 21, 5:57 AM UTC, 13 hours 3 minutes before

AREA FORECAST DISCUSSION...CORRECTION
NATIONAL WEATHER SERVICE TIYAN GU
357 PM CHST MON SEP 21 2015

.SYNOPSIS...A CIRCULATION IS LOCATED WEST OF THE MARINAS.
MODERATE TO FRESH WINDS AND A FEW SHOWERS PREVAIL ACROSS THE
REGION THIS AFTERNOON.

&&

.DISCUSSION...
THIS AFTERNOON A CIRCULATION WAS LOCATED TO THE WEST OF SAIPAN
NEAR 15N144E. THIS CIRCULATION WILL DEVELOP OVER THE NEXT FEW
DAYS AND WILL BECOME A LARGE MONSOON DEPRESSION. IT WILL FURTHER DEVELOP
TO BECOME A TROPICAL DEPRESSION AND A TROPICAL STORM AS THE WEEK
PROGRESSES. WHILE THE CIRCULATION WILL CONTINUE TO MOVE AWAY FROM
THE LOCAL AREA AS IT DEVELOPS IT WILL ENHANCE THE MONSOON ACROSS
THE MARIANAS. THIS WILL KEEP WINDS ELEVATED AND GENERATE A CHANCE
OF SHOWERS AND THUNDERSTORMS AS THROUGH MUCH OF THE WEEK.

AT FIRST IT APPEARED THAT SCATTERED SHOWERS WERE LIKELY TONIGHT
AS RADAR SHOWED A BAND OF SHOWERS SOUTH OF GUAM. THIS AREA
DISSIPATED AS THE AFTERNOON PROGRESSED AND SO ONLY ISOLATED
SHOWERS AND THUNDERSTORMS ARE EXPECTED TONIGHT.

HIGH PRESSURE BUILDING OVER THE AREA IN THE WAKE OF THE SYSTEM
WILL PRODUCE LIGHT WINDS THIS COMING WEEKEND.

&&

.MARINE...
RITIDIAN AND SAIPAN BUOY DATA SHOWS SEAS ARE AROUND 6 FEET.
A NORTHEAST SWELL WILL PERSIST THROUGH THE FORECAST. A SOUTHWEST
SWELL...GENERATED BY MONSOON WINDS ACROSS THE WESTERN PACIFIC WILL
CONTINUE THROUGH TUESDAY NIGHT. THE SOUTHWEST SWELL WILL GRADUALLY
BECOME WEST AND NORTHWEST THE SECOND HALF OF THE COMING WEEK AS THE
INFLUENCE OF THE DEVELOPING TROPICAL DISTURBANCE INCREASES.

WINDS OF 20 TO 25 KNOTS WILL PERSIST THROUGH TUESDAY NIGHT.
SEAS WILL INCREASE TO 8 TO 10 FEET WEDNESDAY THROUGH FRIDAY.
THE COMBINATION OF THE TWO WILL NECESSITATE A SMALL CRAFT
ADVISORY THOUGH FRIDAY.

&&

.EASTERN MICRONESIA...
WEAK RIDGING CONTINUES TO DOMINATE THE PATTERN OVER POHNPEI AND
KOSRAE AND WILL PROMOTE DRIER CONDITIONS ACROSS THE REGION THROUGH
THE WEEK. THE MONSOON TROUGH REMAINS TO THE NORTH OF MICRONESIA WITH
A WEAK CIRCULATION ALONG THE TROUGH TO THE NORTH OF KWAJALEIN. AREAS
OF SCATTERED SHOWERS AND A FEW THUNDERSTORMS REMAIN TO THE NORTH OF
KOSRAE AND POHNPEI AND TO THE SOUTH OF MAJURO. MODELS INDICATE THIS
CIRCULATION WILL DRIFT WESTWARD WITH LITTLE OR NO DEVELOPMENT. AS IT
MOVES WESTWARD...THE EASTERN EDGE OF THE MONSOON TROUGH WILL BE
PULLED FURTHER WEST ALLOWING A FAIR AND DRY PATTERN TO MOVE FROM
MAJURO WESTWARD ACROSS KOSRAE AND POHNPEI.

RESIDUAL MONSOONAL WEST SWELL CONTINUES TO SUBSIDE. SEA CONDITIONS
WILL SUBSIDE ANOTHER FOOT ACROSS THE REGION BY MIDWEEK.

&&

.WESTERN MICRONESIA...
A FEW RESIDUAL SHOWERS WILL MOVE OVER WENO TONIGHT...BUT WILL REMAIN
ISOLATED WITH DECREASING CLOUDINESS AND SHOWERS TOWARD MORNING. THE
SAME RIDGING PATTERN IN PLACE OVER POHNPEI AND KOSRAE WILL SERVE TO
PROMOTE A FAIR WEATHER PATTERN OVER CHUUK THROUGH THE END OF THE
WEEK. THE SCATTERED SHOWERS THAT WERE WEST OF WENO HAVE DECREASED
SIGNIFICANTLY THROUGH THE MORNING HOURS. FOR YAP AND KOROR...
CONVECTION HAS SIGNIFICANTLY DECREASED OVER YAP AND KOROR THROUGH
THE DAY. A TROPICAL DISTURBANCE THAT HAS MOVED TO THE WEST OF THE
MARIANAS WILL BEGIN TO SLOWLY INTENSIFY THROUGH THE NIGHT AS IT
DRIFTS OFF TO THE NORTHWEST. AS THIS OCCURS...WINDS AND CONVERGENCE
WILL INCREASE ACROSS YAP STATE AND NORTHERN PALAU...RESULTING IN
SCATTERED SHOWERS OVER YAP LATER THIS EVENING. THIS BAND OF SHOWERS
AND THUNDERSTORMS WILL BE ON THE NORTHERN EDGE OF KOROR WATERS...SO
KEPT ISOLATED THUNDERSTORMS IN THE FORECAST FOR KOROR THROUGH
TUESDAY. THIS ACTIVITY WILL CONTINUE TO SLOWLY DRIFT NORTHWARD AS
THE MONSOON TROUGH IS PULLED FURTHER NORTH WITH THE MARIANAS
DISTURBANCE.

AS THE DISTURBANCE WEST OF THE MARIANAS SLOWLY STRENGTHENS OVER THE
NEXT FEW DAYS...WINDS ACROSS PALAU AND YAP STATE WILL ALSO INCREASE.
IN RESPONSE TO THE INCREASING WINDS...SEAS AND SURF WILL ALSO BUILD
AT BOTH LOCATIONS. CONDITIONS HAZARDOUS TO SMALL CRAFT ARE LIKELY
TUESDAY MORNING AT BOTH KOROR AND YAP...ALONG WITH SURF RISING TO
HAZARDOUS LEVELS ON WEST AND POSSIBLY SOUTH FACING REEFS AS WELL.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...NONE.
MARIANAS WATERS...SMALL CRAFT ADVISORY UNTIL 6 PM CHST FRIDAY FOR PMZ151>154.

&&

ZIOBRO/KLEESCHULTE

Event by event

1 high surf. Local standard time, as filed.

High Surf, Guam

When: September 22, 5:00 AM GST to September 23, 4:00 AM GST
Where: Guam forecast zone
Deaths: 1 direct, 0 indirect
Reported by: Newspaper

On September 20th a weak tropical disturbance moved across the Marianas. This brought 2 to 3 inches of rainfall to the island. A wind gust to 28 knots (32 mph) was observed at the NWS office with higher gusts seen at Andersen AFB. The heavy rain necessitated the diversion of five flights from the International Airport to|Andersen AFB.

The disturbance moved west of the Marianas and eventually became Tropical Depression 21W on the morning of the 22nd. The system continued to intensify and became Tropical Storm Dujuan as it moved westward. Monsoon winds associated with the intensifying system generated higher seas across the Marianas of between 8 and 9 feet early in the day on the 22nd as observed by the Ritidian Buoy. They did subside to around 7 feet by about 6 pm.

On the 22nd at around 6:30 pm a male Japanese swimmer 23 years of age was observed in distress by the Guam Nikko Hotel Beach Staff. The staff lost sight of the man and a search was conducted by Guam Fire and Police units, U.S. Navy, and U.S.|Coast Guard personnel. Rescue divers from the Guam Fire Department recovered the body of the young man on the morning of the 23rd. His body was found in front of the hotel in 4 to 6 feet of water.

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

Event	Date	Age	Sex	Where	Kind
High Surf, Guam	2015-09-22	23	Male	In Water	Direct

What these are

High Surf: Large waves breaking on the shore that caused damage, erosion or casualties.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Guam in 2015 Every state in 2015 This day in weather history Warnings in Guam, September 2015

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 608218.