FXPQ50 PGUM 190918

AFDGUM



Area Forecast Discussion

National Weather Service Tiyan GU

718 PM ChST Thu Mar 19 2026



.Marianas Synopsis...

Satellite imagery shows partly skies. Radar imagery shows isolated 

showers over the coastal waters. Altimetry shows combined seas of 9 

to 11 feet to the east of the islands, and Ipan Buoy data shows 6 

feet at 15 seconds. 



There remains a Small Craft Advisory, High Surf Advisory, Coastal 

Flood Watch and High Risk of Rip Currents statements.



&&



.Discussion...

A drier pattern remains over the islands for the next few days. 

Model guidance suggests the next round of showers may arrive around 

the middle of next week as a new injection of moistness may enter the

region from Micronesia. 



&&



.Marine...

Marine conditions are expected to remain elevated for the next

several days. Seas may periodically drop below 10 feet, while surf 

may also occasionally drop below 9 feet during this time. However, 

they are expected to bounce back up shortly thereafter. Models 

suggest Guam and Rota will be the first to experience seas that 

remain below 10 feet, then, seas at Tinian and Saipan should subside

a day or so later.



&&



.Eastern Micronesia...

Troughing continues across central Micronesia this afternoon with a 

broad trough located just west of eastern Micronesia. This feature 

will try to shift eastward through tonight as the trade-wind pattern 

becomes more established across the region and limits its forward 

propagation. The trough will stall near Kosrae and promote scattered 

showers and isolated thunderstorms near the island. Locally heavy 

rainfall will be possible at Kosrae through tonight as a result. 

Gusty and erratic winds will also be possible with any heavy showers 

and strong thunderstorms. Scattered showers and isolated 

thunderstorms are expected at Majuro through at least Friday 

afternoon as weak troughing continues to impact portions of the 

Marshall Islands. Isolated to low-end scattered showers will prevail 

at Pohnpei through Friday, with a stray thunderstorm or two also 

possible. Light to gentle east to southeast winds will continue to 

develop at all forecast sites by early Friday with these conditions 

expected to persist through the weekend. 



A long-period north-northwest and a long-period northeast swell 

persist across the waters and are expected to stick around for the 

next couple of days. Hazardous surf along north facing reefs at both 

Pohnpei and Kosrae will continue through tonight and surf conditions 

are expected to fall below 9 feet along north facing reefs at Kosrae 

thereafter. Higher surf conditions are expected to continue along the

north facing reefs of Pohnpei based on the latest model guidance and

the advisory will likely need to be extended or at least reissued 

for the weekend as another push of a north swell enters the region. 

Combined seas are expected to generally range between 5 to 8 feet 

through Friday at all forecast sites, with seas falling to 4 to 6 

feet by early next week.



&&



.Western Micronesia...

A fairly dry pattern remains across western Micronesia this evening,

with the latest satellite data showing partly cloudy skies and

isolated showers across the region. This pattern looks to continue

through the weekend for Yap and Palau. Chuuk will see an increase in

showers Friday into Friday night as a weak trough moves through the

state, bringing low-end scattered showers and isolated thunderstorms

to Weno. This feature will move slowly westward into Yap Proper

Monday and into Palau Tuesday. 



The marine forecast remains relatively unchanged. The northeast swell

has subsided enough to allow surf to fall below hazardous levels at

both Palau and Chuuk. However, latest altimetry shows seas remain

elevated at Yap, with model guidance indicating the north-northeast

swell will remain high enough to maintain hazardous surf conditions

that continues through Saturday afternoon. Otherwise, gentle to

moderate winds are expected across Chuuk through Friday night, and 

at Yap and Palau through the weekend.



&&



.GUM WATCHES/WARNINGS/ADVISORIES...

GU...High Rip Current Risk through Friday afternoon for GUZ001.



     High Surf Advisory until 4 PM ChST Friday for GUZ001.



MP...High Rip Current Risk through Friday afternoon for MPZ001>003.



     High Surf Advisory until 4 PM ChST Friday for MPZ001>003.



Marianas Waters...Small Craft Advisory until 5 PM ChST this afternoon 

	 for PMZ151>154.



&&



$$



Marianas: Bowsher

East Micronesia: Whisnant

West Micronesia: Kleeschulte