Guam, 2003

Funnel Cloud in Guam, August 5, 2003

August 5, 2003 · NWS GUA · 1 event in 1 county or zone

At least three funnel clouds were spotted over Guam during the afternoon from 1551 to 1646 The observer from the National Weather Service Office at Tiyan, saw a funnel cloud to the northeast of the office from 1551 to 1616, a secound funnel cloud was spotted to the south of the office from 1628 to 1646. A third funnel cloud was spotted from Andersen Air Force Base.

The toll

Deaths
0
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 GUA wrote it up.

At least three funnel clouds were spotted over Guam during the afternoon from 1551 to 1646 The observer from the National Weather Service Office at Tiyan, saw a funnel cloud to the northeast of the office from 1551 to 1616, a secound funnel cloud was spotted to the south of the office from 1628 to 1646. A third funnel cloud was spotted from Andersen Air Force Base. The Air Force observer spotted the funnel cloud at 1559 to the southwest of the station.

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 GUA wrote its last area forecast discussion before the first event at Aug 5, 3:45 PM SST, 6 minutes earlier.

Area forecast discussion, Aug 5, 3:45 PM SST, 6 minutes before
AREA SYNOPTIC DISCUSSION
NATIONAL WEATHER SERVICE TIYAN GU
1 PM GUAM LST WED AUG 6 2003

WESTERN NORTH PACIFIC BETWEEN EQUATOR AND 25N FROM 130E TO 180.

TYPHOON ETAU IS CENTERED NEAR 22N129E MOVING NORTHWEST OUT OF THE
DISCUSSION AREA AT 15 MPH WITH MAXIMUM SUSTAINED WINDS OF 110 MPH.
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ASSOCIATED WITH THE
TYPHOON ARE LOCATED BETWEEN 15N AND 25N FROM 130E TO 133E. REFER TO
JOINT TYPHOON WARNING CENTER BULLETIN WTPN32 PGTW FOR ADDITIONAL
INFORMATION.

A MONSOON TROUGH EXTENDS FROM TYPHOON ETAU SOUTHEASTWARD TO NEAR
6N147E. LOW-LEVEL CONVERGENCE ASSOCIATED WITH THE MONSOON TROUGH IS
PRODUCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN YAP STATE
BETWEEN THE EQUATOR AND 13N FROM 136E TO 148E.

A NEAR-EQUATORIAL TROUGH EXTENDING FROM NEAR 6N147E TO NEAR 5N155E
IS PRODUCING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN POHNPEI
STATE BETWEEN 3N AND 7N FROM 153E TO 158E.

SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE ALSO DEVELOPING
NORTHEAST OF THE MONSOON TROUGH BETWEEN 14N AND 18N FROM 146E TO
155E...EAST OF THE MARIANA ISLANDS.

UPPER-LEVEL DIVERGENCE NORTH OF MARIANAS IS PRODUCING ISOLATED
SHOWERS AND THUNDERSTORMS BETWEEN 20N AND 25N FROM 142E TO 150E.

Event by event

1 funnel cloud. Local standard time, as filed.

Funnel Cloud, Guam

When
August 5, 3:51 PM SST to 4:46 PM SST
Where
Guam County, Countywide
Reported by
OFFICIAL NWS OBS.

What these are

Funnel Cloud
A rotating column of cloud extending from a thunderstorm that did not reach the ground.

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

The same day elsewhere

More

Every storm in Guam in 2003Every state in 2003This day in weather historyWarnings in Guam, August 2003

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: 5338227.