Name: Tropical Depression in Guam, December 11 to 12, 2008
Start: 2008-12-11T00:00
End: 2008-12-12T10:00
Location: Guam

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 2

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.

Tropical Depression (TD) 27W developed late Wednesday evening December 10th about 450 miles east-southeast of Guam. Moving steadily west-northwestward at 20 to 25 mph, TD 27W passed about 30 miles south of Guam at 1700GST on the afternoon of Thursday December 11th with maximum sustained winds near 35 mph. As it passed, TD 27W brought some wind gusts over 50 mph to Guam,and over 40 mph to Rota, but only modest rainfall. Further north, maximum wind gusts at Tinian and Saipan were all less than 39 mph.

On Guam, the airport reported a maximum sustained wind of 33 mph from the northeast at 1337 GST, and a peak gust of 41 mph from the northeast at 1336 GST. The highest sustained wind anywhere on the island was from the southeast at 39 mph at the automated station at Apra Harbor at 1851 GST. Apra Harbor also had the island's peak gust of 55 mph from the east-southeast in the hour ending at 1751 GST. Rainfall around the island was generally less than an inch, but the automated station at Merizo in southern Guam reported 2 inches in the 24 hours ending at 0900 GST Friday morning the 12th. The lowest sea-level pressure at the airport was 1000.2 mb at 1554 GST on the 11th.

On Rota, the automated station at the airport reported a maximum wind gust of 43 mph from the northeast at 1351 GST, while sustained winds never exceeded 25 mph. Rainfall was insignificant.

No significant damage was reported on Guam or Rota.

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 Dec 10, 9:45 AM UTC, 4 hours 15 minutes earlier.

Area forecast discussion, Dec 10, 9:45 AM UTC, 4 hours 15 minutes before

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TIYAN GU
745 PM CHST WED DEC 10 2008

UPDATED TO ADD MICRONESIAN SECTIONS

.SYNOPSIS...
VISIBLE SATELLITE SHOWS THE CIRCULATION ESE OF GUAM CLEARLY WITH
THE CENTER NEAR 11N152E...RIGHT WHERE THE GFS SAYS IT SHOULD BE.
WHILE THE DEEP CONVECTION IS LIMITED...THERE ARE PLENTY OF LOW-
LEVEL CLOUD/SHOWER LINES SPIRALING INTO THE CENTER. SOME OF THESE
ARE ALREADY EVIDENT ON RADAR OUT TO THE EAST.

&&

.DISCUSSION...
LATEST MODELS SHOW LITTLE CHANGE FROM PREVIOUS RUNS...BRINGING
THIS ODDBALL CIRCULATION FEATURE THROUGH THE MARIANAS THURSDAY
NIGHT...WITH THE CENTER PASSING SOUTH OF GUAM. ALONG WITH SCATTERED
SHOWERS...THE PASSAGE OF THE LOW WILL LIKELY BRING BREEZY CONDITIONS
AT TIMES THURSDAY NIGHT AND FRIDAY AS THE ENHANCED PRESSURE GRADIENT
NORTH OF THE CENTER CRANKS WINDS UP TO 15 TO 25 MPH.

&&

.MARINE/SURF...
UPDATED THE WIND WAVES AND LOADED IN LATEST WW3 WAVE HEIGHTS...
BUT NO REAL CHANGES MADE TO SWELL GRIDS AS THEY WERE ALREADY IN
GOOD SHAPE. HIGH SURF AND HAZARDOUS SEAS SHOULD LAST THROUGH
FRIDAY...THEN FALL SLOWLY OVER THE WEEKEND. ENHANCED WINDS
MENTIONED ABOVE FOR THURSDAY NIGHT AND FRIDAY MAY EXCEED SMALL
CRAFT WIND CRITERIA DURING THAT TIME...ESPECIALLY IN SAIPAN AND
TINIAN WATERS.

&&

.EASTERN MICRONESIA...
THE HIGH SURF WARNINGS FOR KOSRAE AND POHNPEI CONTINUE WITH SURF
HEIGHTS AROUND THE THRESHOLD FOR A WARNING. CLOUD COVER OVER POHNPEI
HAS THINNED BUT THERE IS STILL A LITTLE UPPER-LEVEL DIVERGENCE AND A
LOW BROKEN CEILING AND INTERMITTENT RAIN AT FORECAST TIME SO
SCATTERED SHOWERS WERE FORECASTED FOR TONIGHT. KOSRAE AND MAJURO ARE
IN THE CLEAR WITH A LITTLE CONVECTION  AND THE FLAT REMNANTS OF A
DISSIPATED CIRCULATION NEAR KOSRAE.  THE FORECAST FOR KOSRAE TONIGHT
IS MOSTLY CLOUDY WITH ISOLATED SHOWERS AND THE FORECAST FOR MAJURO
IS PARTLY CLOUDY WITH ISOLATED SHOWERS. CONTINUED WITH PREVIOUS
FORECAST TREND OF ISOLATED SHOWERS FOR THE REST OF THE FORECAST
PERIOD.

LATEST WW3 INDICATES STRONG NORTHERLY SWELLS SUBSIDING THROUGH
THURSDAY BUT WITH ANOTHER ROUND OF STRONG NORTHEAST SWELLS ARRIVING
THIS WEEKEND.

&&

.WESTERN MICRONESIA...
HIGH SURF WARNING CONTINUES FOR CHUUK WHERE WW3 INDICATES NNE SWELL
OF 12 TO 13 FEET TONIGHT. SURF TONIGHT IN THE RANGE OF 15 TO 16 FEET
WILL SUBSIDE BELOW 15 FEET THURSDAY...BUT LONG PERIOD NE SWELL OF 9
FEET WILL CONTINUE UNTIL FRIDAY. MODEL GUIDANCE INDICATES THE
CIRCULATION CENTER NEAR 12N152E WILL WEAKEN AND MOVE WESTWARD TO
JUST NORTHEAST OF YAP BY FRIDAY AFTERNOON. SIGNIFICANT AFFECTS ARE
DOUBTFUL AT THIS TIME. FOR NOW ONLY MINOR TWEAKS TO WESTERN
MICRONESIA FORECASTS.

HIGH SURF WARNING REMAINS IN EFFECT FOR CHUUK WITH ADVISORIES FOR
YAP AND PALAU.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...HIGH SURF ADVISORY UNTIL 6 PM CHST FRIDAY FOR GUZ001>004.

MARIANAS WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
     6 PM CHST FRIDAY FOR PMZ151>154.

&&

MIDDLEBROOKE/DEVITA

In the hours before

Special weather statement, Dec 10, 1:00 PM UTC, 1 hour before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TIYAN GU
11 PM CHST WED DEC 10 2008

GUZ001>004-PMZ151>154-110200-
GUAM-ROTA-TINIAN-SAIPAN-MARIANAS COASTAL WATERS-
11 PM CHST WED DEC 10 2008

...TROPICAL DISTURBANCE APPROACHING THE MARIANAS...

A TROPICAL DISTURBANCE WAS LOCATED NEAR 12N151E OR ABOUT 430 MILES
EAST-SOUTHEAST OF GUAM AT 10 PM WEDNESDAY NIGHT CHST. THE
DISTURBANCE IS MOVING WESTWARD ABOUT 15 TO 20 MPH.

SATELLITE IMAGERY SHOWS SCATTERED SHOWERS AND A FEW THUNDERSTORMS
ASSOCIATED WITH THE CIRCULATION. WINDS ARE ESTIMATED TO BE 25 TO 30
MPH NEAR THE CENTER OF THE DISTURBANCE.

THE CENTER OF THE TROPICAL DISTURBANCE IS EXPECTED TO PASS CLOSE TO
OR JUST SOUTH OF THE ISLAND OF GUAM LATE THURSDAY NIGHT OR EARLY
FRIDAY MORNING.

THIS DISTURBANCE IS EXPECTED TO BRING SCATTERED SHOWERS AND BREEZY
CONDITIONS TO THE MARIANAS THURSDAY NIGHT AND FRIDAY. A FEW
THUNDERSTORMS ARE ALSO POSSIBLE. WINDS ARE EXPECTED TO BE BETWEEN 15
TO 25 MPH...BUT COULD GUST AS HIGH AS 35 MPH IN SHOWERS.

THIS DISTURBANCE IS NOT EXPECTED TO INTENSIFY ENOUGH TO WARRANT A
TROPICAL CYCLONE WARNING.

WE WILL CONTINUE TO MONITOR THIS SYSTEM AND WILL UPDATE THIS
STATEMENT IF NEEDED.

ZIOBRO

Event by event

2 tropical depression. Local standard time, as filed.

Tropical Depression, Guam

When: December 11, 12:00 AM GST to December 12, 10:00 AM GST
Where: Guam forecast zone
Reported by: Official NWS Observations

Tropical Depression, Rota

When: December 11, 12:00 AM GST to December 12, 12:00 AM GST
Where: Rota forecast zone
Reported by: Official NWS Observations

What these are

Tropical Depression: A tropical cyclone with sustained winds below 34 knots.

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

The same day elsewhere

More

Every storm in Guam in 2008 Every state in 2008 This day in weather history Warnings in Guam, December 2008 The 2008 hurricane season

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: 141652, 141653.