Drought in Guam, November 1 to 30, 2021

Area Forecast Discussion
National Weather Service Tiyan GU
657 PM ChST Sun Oct 31 2021

.Marianas Synopsis...
A few showers and thunderstorms were over the Marianas this late
afternoon. Little will change the next few days.

.Discussion...
A few small changes made to the forecast. The surface trough that
brought scattered showers and isolated thunderstorms Sunday afternoon
has moved west of the Marianas. A few showers and thunderstorms are
possible tonight in the wake of the trough. Deep-layer moisture will
remain high enough through much of the week to produce isolated
showers and thunderstorms through Thursday night. Moisture will
decrease by the end of the week and only isolated showers are
predicted Friday through Sunday.

&&

Marine/Surf...
Ipan buoy showed and east swell and seas between 5 to 6 feet this
afternoon. The east swell height was about 2 feet high. Models also
show a northerly swell passing over the area. Observations from the
afternoon indicated that the north swell had risen high enough to
produce hazardous surf. Wave Watch model data was too low but the
Near Shore Wave Prediction model seemed to depict the situation in
a reasonable way. Near Shore keeps the surf hazardous through Monday
afternoon. Surf heights on north and west facing reefs are predicted
to be 9 to 11 feet tonight decreasing to 7 to 9 feet Monday
afternoon. The rip current risk will be high on north and west
facing reefs through Monday afternoon. The north swell is likely to
have been generated from ex-typhoon Malou that was north of the area
a few days ago. Models show sea heights of 6 to 8 feet tonight
decreasing to 5 to 7 feet Monday.

&&

.Eastern Micronesia...
Gentle to moderate trades prevail in eastern Micronesia. bringing
quieter conditions through Monday morning. After, a series of
disturbances and convergent trade-wind flow will continue to make
their way west, bringing increasing showers and thunderstorm
potential. One major trade-wind surge will arrive at Majuro on
Tuesday night, then making its way across Kosrae on Wednesday night,
and then across Pohnpei sometime by the weekend. After the surge
passes, the islands will return to drier conditions.

The seas will stay slightly elevated, as passing disturbances
generate higher wind waves, in combination with a distant north swell
from a cyclone in the northern Pacific.

Pohnpei and Kosrae will see combined seas of 4 to 6 feet tonight,
before diminishing slowly to between 3 and 5 feet by Wednesday, after
which the trade-wind surge will bring wind waves to increase the
seas back up to between 4 and 6 feet. Majuro will see combined seas
between 5 and 6 feet tonight, before a slight decrease by Tuesday
night and shoot up to between 6 and 8 feet by the weekend, as higher
wind waves and the north swell make it to the Marshall Islands.

&&

.Western Micronesia...
A broad trough with multiple embedded weak circulations are bringing
scattered showers and isolated thunderstorms to Palau and Yap
tonight, with locally heavy showers possible for Yap through
midnight. Meanwhile, Chuuk is under moderate trade-wind flow with
mostly clear skies and drier weather.

The disturbances will continue to bring heavier showers and higher
thunderstorm potential for Palau and Yap as they make their way
northwest. Model guidance indicates that the trough will continue to
keep Yap under unstable convergent flow in its wake until sometime
Monday night, meanwhile Palau should see drier conditions Monday
morning. Based on model guidance and visible satellite imagery, the
potential for these disturbances to consolidate into something more
substantial is becoming less and less probable, and as such, are most
likely going to stay as a trough passing over the Philippines. This
feature will still be monitored for further development.

After, the islands will be situated in a ridge that will help sustain
lesser showers and clearer skies through at least midweek. Chuuk will
encounter a series of passing troughs throughout the week, bringing
periods of wetter and drier conditions along the way.

Combined seas for stay elevated at 5 to 6 feet for Palau and 5 to 7
feet for Yap tonight. As the distant north swell and passing
disturbances continue to weaken, seas will slowly diminish to between
3 and 4 feet by Tuesday, staying in similar conditions through the
weekend. Chuuk will see combined seas of 5 to 6 feet through Monday
afternoon, before slowly decreasing to between 3 and 5 feet sometime
midweek.

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...High Surf Advisory until 6 PM ChST Monday for GUZ001>004.

MP...None.
Marianas Waters...None.
&&

Marianas: Ziobro
Micronesia: Pavliukoit