432
FXPQ50 PGUM 230729
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
529 PM ChST Sun Nov 23 2025

.Marianas Synopsis...
Satellite and radar this afternoon depicts isolated showers and
partly cloudy skies over Marianas coastal waters, with pockets of
scattered showers just further northeast over the open ocean,
associated with broad, subtle troughing nearby. Buoys and altimetry
data indicate combined seas remain near 7 to 9 feet.

&&

.Discussion...
A dry trade wind pattern continues. CIMSS MIMIC Total Precipitable
Water (TPW) imagery shows a plume of dry air over the Marianas with
TPW values around 1.2 to 1.7 inches, with a slight moistening trend
heading into the evening, which could support a very slight bump in
showers with help from nocturnal instability. Overall however,
isolated showers are expected to continue tonight through much of the
week. A slightly wetter pattern looks to take shape in the latter
half as the subtropical ridge weakens north of the Marianas with a
subsequent easing of the trade winds, allowing for a few weak
troughs to cross the area through the weekend. For now, held off on
the increase to scattered showers until Saturday night, but shower
chances will likely be adjusted in later forecasts as the pattern
becomes clearer.

&&

.Marine/Surf...
Moderate to fresh trade winds will prevail across the region through
the next day or two, gradually diminishing to become gentle to
moderate through the latter half of the week. Combined seas of 7
to 9 feet will also gradually decrease by 1 to 2 feet by the end
of the week, as the elevated trade swell and wind waves become
more relaxed. Although combined seas and winds remain below
criteria hazardous to small craft, sea conditions will remain choppy
for the next few days, especially over eastern coastal waters. As the
elevated trade swell is expected to persist into midweek, the high
risk of rip currents along east facing reefs is now expected through
at least Wednesday night, decreasing to moderate as the trade swell
eases. A moderate risk of rip currents is still expected along north
and south facing reefs for the next few days, as the elevated trade
swell wraps around the islands and increases surf along these
exposures.

&&

.Tropical Systems...
A weak tropical disturbance, Invest 92W, is centered just north of
Koror, Palau near 8N134E, moving north-northwest across the
Philippine Sea. Invest 92W was responsible for numerous to
widespread showers and isolated thunderstorms across Palau and Yap
Proper over the past 24 hours, with locally heavy rainfall and
strong gusty winds. Invest 92W is expected to begin to strengthen as
it moves away from Palau and Yap toward the Philippines. 92W is not
expected to directly impact Palau or Yap as a tropical cyclone,
however, both locations will continue to experience showers,
thunderstorms and gusty winds as it continues to move northwest.
Invest 92W will continue to be monitored as it moves across the
Philippine Sea.

&&

.Eastern Micronesia...
A dry pattern is currently in place across Kosrae and Pohnpei, with a
weak Inter-Tropical Convergence Zone (ITCZ) seen across the southern
Marshall Islands. Buoys and altimetry show seas between 5 and 8 feet
across the region, with higher seas north of Pohnpei and east of
Majuro.

A weak ITCZ stretches west across the Marshall Islands while a weak
trade-wind trough is approaching Majuro. These two features are
interacting to produce scattered showers and isolated thunderstorms
across the atoll this evening. The ITCZ is expected to continue to
slowly develop westward over the next couple of days as additional
trade-wind troughs traverse the ITCZ. Showers are expected to remain
low-end scattered through Monday night before increasing as the ITCZ
becomes a bit more organized. For Kosrae, the dry pattern there is
expected to break down later tonight as the west end of the weak ITCZ
pushes into the state along with an approaching trade-wind trough.
After midnight, scattered showers and isolated thunderstorms are
expected to move into Kosrae, with increased convection along the
ITCZ to continue through at least midweek, with a drier pattern
moving back in Friday. For Pohnpei, the drier pattern looks to
continue there through Tuesday night, with the ITCZ finally
developing over the state around the middle of the week. Increased
convection is then expected to continue across Pohnpei through at
least Friday.

Combined seas of 6 to 8 feet for Pohnpei are expected to subside
over the next few days, reaching 4 to 6 feet Tuesday through the end
of the week. For Kosrae, seas of 4 to 6 feet tonight will subside to
between 4 and 5 feet Tuesday night. Seas are then expected to build
slightly to between 4 and 6 feet Wednesday as a more east swell moves
into the region. Majuro sees seas between 6 and 8 feet through
Wednesday, with seas only dropping about 1 foot, to between 5 and 7
feet for the remainder of the week. Moderate to fresh trade winds at
Pohnpei tonight are expected to become gentle to moderate through
the remainder of the week. Mostly gentle to occasionally moderate
trade winds are expected at Kosrae through the week. For Majuro,
gentle to moderate trade winds through the week will become
occasionally fresh Tuesday and Tuesday night.

&&

.Western Micronesia...
A weak tropical disturbance, Invest 92W, is within a Near-
Equatorial Trough (NET) and is located near Palau at about 8N134E.
The disturbance has an elongated circulation and is still poorly
organized, with the bulk of deep convection along the northern edge
of the disturbance. ASCAT analysis also shows surging trades along
this area of convergence, just northwest of Yap Proper. Still,
unsettled weather, fresh to strong gusts, and choppy seas are
expected for Palau through tonight and for Yap through Monday, until
Invest 92W moves farther west into the Philippine Sea. As of this
afternoon, 24-hour rainfall amounts reveal about 2.53 inches have
fallen at Yap and 0.85 inches at Palau. Models show a similar
distribution of rainfall, with 1 to 2 inches possible for Yap and 0.5
to 1.0 inches for Palau tonight and Monday. As Invest 92W drifts
west-northwest over the next couple days, conditions are expected to
trend down to light to moderate winds and isolated showers by
midweek.

For Chuuk, low-end scattered showers are moving in from the
northeast. These shallow, fast-moving showers are expected to bring
occasional gusts to 25 kt tonight. Otherwise, relatively quiet
weather is expected for much of the work week as minor troughs pass
through. Then, the ITCZ in eastern Micronesia begins to extend into
Chuuk State late week, bringing another increase in showers.

Altimetry data indicates seas are 5 to 7 feet around Palau and 6 to
9 feet near Yap and Chuuk. As Invest 92W gradually moves west-
northwest, continue to expect choppy seas around Palau through
tonight and at Yap through Monday. The Small Craft Advisory for Yap
was extended another 12 hours to account for latest model guidance
suggesting hazardous winds (greater than 22 knots) continue across
coastal waters through early Monday morning. The northeast swell
generated by the trade-wind surge continues to support elevated surf
along north and east facing reefs of Chuuk through tonight, then in
the latter half of the week, seas decrease to 5 to 7 feet as the
trade-wind surge and swell begins to subside.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...High Rip Current Risk through late Monday night for GUZ001.

MP...High Rip Current Risk through late Monday night for MPZ001>003.

Marianas Waters...None.
&&

$$

Marianas: DeCou
East Micronesia/Tropical: Kleeschulte
West Micronesia: Cruz