FNMY50 PGUM 121908

FWFGUM



Fire Weather Planning Forecast for Guam

National Weather Service Tiyan GU

508 AM ChST Sat Dec 13 2025



.Discussion...

0.02 inches of rain fell at Guam International Airport yesterday,

which maintained the 0.2 subtraction. The KBDI has now risen to 417,

still in the moderate fire danger category, but over halfway to the

high category. An approaching shear line will stay mainly north of

Saipan, although it could bring increased clouds and a few showers.

The current forecast is leaning towards lighter showers so not

expecting much rainfall. Shear lines, and their associated increase

in winds, are typically more common in January and February as strong

cold fronts move southward from Japan and then decay north of the

Marianas, becoming shear lines. As long periods of dry weather

continue, the KBDI will climb and the fire danger rating will

eventually increase, especially on days when winds become breezy;

probably not until January though.



GUZ001-131915-

Guam-

508 AM ChST Sat Dec 13 2025



                      Today        Tonight      Sun          



Cloud Cover           Pcldy        Mcldy        Mcldy        

Precip Type           Showers      Showers      Showers      

Chance Rain (%)       20           20           20           

Temp                  86           76           87           

RH %                  71           100          71           

20FtWnd-Val/AM(mph)   E 10                      E 12         

20FtWnd-Rdg/PM(mph)   E 11         E 11         E 13         

Mixing Hgt(ft-msl)    6087         1            5984         

Transport Wnd (mph)   E 23         E  8         E 29         



$$





.Forecast for Days 3 Through 7...



.SUNDAY NIGHT...Partly cloudy with isolated showers. Lows in the

upper 70s. East winds 10 to 15 mph. 

.MONDAY...Mostly sunny with isolated showers. Highs in the upper

80s. East winds 10 to 15 mph. 

.MONDAY NIGHT...Mostly cloudy with a slight chance of showers.

Lows in the upper 70s. Northeast winds 10 to 15 mph. 

.TUESDAY...Mostly sunny with a slight chance of showers. Highs in

the upper 80s. East winds 10 to 15 mph. 

.TUESDAY NIGHT...Partly cloudy with a slight chance of showers.

Lows in the upper 70s. East winds 10 to 15 mph. 

.WEDNESDAY...Mostly sunny with a slight chance of showers. Highs

in the upper 80s. East winds 10 to 15 mph. 

.WEDNESDAY NIGHT...Partly cloudy with a slight chance of showers.

Lows in the upper 70s. East winds 10 to 15 mph. 

.THURSDAY...Mostly sunny with a slight chance of showers. Highs

in the upper 80s. East winds 10 to 15 mph. 

.THURSDAY NIGHT...Partly cloudy with a slight chance of showers.

Lows in the upper 70s. East winds 10 to 15 mph. 

.FRIDAY...Mostly sunny with a slight chance of showers. Highs in

the upper 80s. East winds 10 to 20 mph. 





$$