434
FXPQ50 PGUM 160849
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
649 PM ChST Thu Jan 16 2025

.Marianas Synopsis...
Current satellite shows lines of isolated showers crossing the
Marianas, mainly Rota northward, oriented along a shallow trade-wind
trough crossing the area. Satellite trends show mostly quiet
conditions upstream. Winds have decreased this afternoon after
somewhat gusty conditions this morning; surface observations show
moderate speeds with occasional gusts to around 20 mph.

&&

.Discussion...
A dry trade-wind pattern prevails across the region, with only
isolated showers expected throughout the forecast period. Occasional
passing surface troughs or areas of trade-wind convergence will
increase shower coverage from time to time over the next few days.
Model and satellite trends indicate a shallow surface trough crossing
the Marianas tomorrow, but precipitable water values will remain
quite low. The marine and surf forecasts remain the main concern, but
sea conditions look to ease over the next few days as the westward
extent of the trade-wind surge that has dominated the region
diminishes near the Marianas.

&&

.Marine...
Buoys show combined seas of 7 to 10 feet within Marianas waters,
which are forecast to gradually diminish overnight, falling below
hazardous levels for small craft by Friday morning. A high risk of
rip currents continues for north and east facing reefs due to
elevated trade swell and northerly swell, which is also contributing
to hazardous surf for north facing reefs. The risk of rip currents
for north and east reefs will diminish over the next few days as
trade swells and northerly swells ease downward, decreasing to
moderate by early next week. Winds are expected to be moderate to
fresh with occasional strong gusts through tonight due to a weakening
shear line stalled north of the area. Winds should relax thereafter,
becoming gentle to moderate this weekend through early next week.

&&

.Eastern Micronesia...
High Surf Advisory and Small Craft Advisory for Pohnpei, Kosrae and
Pohnpei have been extended thru Monday. Pohnpei Buoy shows combined
seas of 9 to 11 feet and Kosrae/Utwe Buoy, which is shaded from the
north and northeast, shows seas of 7 to 9 feet, both with occasional
larger waves. Models indicate elevated winds and sea conditions will
persist. Also, another pulse of northerly swell will move through the
region, mainly Friday through Sunday, and that will cause seas to be
very choppy at some locations. The surf remains elevated along north
facing reefs, but currently below hazardous criteria levels. The
arriving northerly swell could possibly make surf hazardous along
north facing reefs over the weekend.

Weatherwise, satellite visible images show a dry weather regime over
the region, except where patchy showers are triggered by surging
trade winds. Models indicate patchy showers at times could move
across the region thru this weekend, otherwise little change in this
dry, strong trade-wind flow is expected through the longer term.

&&

.Western Micronesia...
Diffusive trade-wind regime will continue to keep drier conditions
at all Palau, Yap, and Chuuk the next few days. Showers will once
again become more patchy in nature at Palau and Yap during the
weekend, as another trade-wind surge moves in next week. Chuuk is
expected to see further drying through the weekend, as wetting rains
appear less likely over the next several days, but a passing trough
may bring low-end scattered showers early next week.

Combined seas of 6 to 9 feet at Palau and Yap are expected to persist
through the weekend, followed by a drop in 1 to 2 feet, as trade
swell and various north swells weaken. Seas of 7 to 10 feet are
expected at Chuuk through Friday afternoon, so a Small Craft Advisory
still remains valid at this time. These swells are also expected to
continue producing hazardous surf along north facing reefs of Palau,
Yap and Chuuk through at least Friday afternoon. It is likely for the
High Surf Advisory to persist at Chuuk through the weekend, so the
Advisory may be extended if conditions warrant.

&&

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

     High Surf Advisory until 6 AM ChST Friday for GUZ001.

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

     High Surf Advisory until 6 AM ChST Friday for MPZ001>003.

Marianas Waters...Small Craft Advisory until 6 AM ChST Friday for PMZ151>154.

&&

$$

Marianas: DeCou
East Micronesia: Simpson
West Micronesia: Montvila