590
FXPQ50 PGUM 202058
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
658 AM ChST Fri Jun 21 2024

.Marianas Synopsis...
Satellite shows partly cloudy skies with isolated showers moving
through the Marianas Waters. The Ritidian buoy reveals combined seas
of 2 to 4 feet, composed mainly of a 2 to 3 foot east swell and wind
waves.

&&

.Discussion...
Trade winds will remain in charge of weather for the Marianas through
the next several days. A disturbance is passing south of Guam today,
we could get some mid to high level blowoff from that, it will have
little in the way of showers with it though. Models are showing some
increased moisture around Monday, will review further to see if we
should nudge up to scattered showers around that time. We currently
have skies becoming mostly cloudy at night.

In the longer term, the GFS is now looking less inclined to blow up a
big monsoon trough, what a surprise. It gave up even sooner than I
though it would. It is still trying to hang onto something west of
the Philippines, in the South China Sea. ECMWF-HiRes has also backed
off on its activity, it does agree at least somewhat on that activity
west of the Philippines though, with the caveat that whatever is
going to happen had better hurry, it only has a few days. The
Canadian Ensemble is showing something interesting though, around
Sunday a monsoon trough emerges into Micronesia. The trough then
persists through the first week of July, so it could be the real
deal. That`s what helps create our wet season, so it could be just
around the corner.

&&

.Marine...
Combined seas will remain quite low at 2 to 4 feet through Saturday
night. This will allow the risk of rip currents to become low
tonight. Winds will remain gentle to moderate through next Tuesday.
With seas capping at 7 feet and winds staying at or below 17 knots,
that means benign marine conditions will continue into next week.

&&

.Eastern Micronesia...
An Area of convergent trade winds is seen southeast of Kosrae and the
ITCZ is moving into the AOR southeast of Majuro. Scattered showers
are expected for all three forecast areas. Majuro is expected to
have the highest shower potential tonight as the ITCZ moves across,
though models indicate that the ITCZ will peak before it gets to
Majuro. Pohnpei and Kosrae will get scattered showers on and off
through the weekend into early next week as weak troughs pass through
a broad convergent trade-wind pattern.

Echoing the previous AFD: Gentle to moderate trades and combined
seas of 3 to 5 feet are expected at Kosrae and Pohnpei, with combined
seas of 3 to 5 feet rising a foot this weekend at Majuro and
persisting through early next week. Altimetry passes this afternoon
show combined seas of 3 to 5 feet over the region, with combined seas
of 4 to 6 feet seen near the International Date Line.

&&

.Western Micronesia...
Currently showers and isolated thunderstorms are seen over Chuuk`s
waters, this is expected to pass this morning with the trough still
remaining active. Isolated showers are expected for Chuuk tonight and
for another day or two. A weak monsoon trough is seen near Koror. It
is expected to weaken with a trade wind pattern beginning around the
weekend. Scattered showers are expected for Yap and Koror with a
higher shower potential for Koror this morning due to surface
convergence and southerly flow. The weekend looks to be on and off
scattered showers, but becoming a bit more showery mid week as a
broad area of trade convergence develops and moves across all three
forecast points.

Echoing the previous AFD: Gentle trades and benign sea conditions
are expected to persist through early next week at Chuuk, Yap, and
Palau. Altimetry passes this afternoon show combined seas are around
3 feet across the region.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...None.
MP...None.
Marianas Waters...None.
&&

$$

Marianas: Stanko
Micronesia: Hong