Area Forecast Discussion
Issued by NWS
FXPQ60 PGUM 192200
Area Forecast Discussion
National Weather Service Tiyan GU
719 AM ChST Mon Feb 20 2017
.Marianas Synopsis... Northeast winds, mostly cloudy skies and
isolated showers prevail across the local area this morning.
The shear line that plagued the Marianas for much of the last week
has finally dissipated. Drier weather with partly cloudy skies
and only a few showers are expected through the coming week. The
area of high pressure that help generate breezy conditions the
last few days is moving away. Another high pressure center is
moving out into the Northwest Pacific, but it is not as strong as
the previous high. Expect winds of 15 to 20 mph today with little
change through the week.
Observations from the Ritidian, Tanapag and Ipan buoys indicate
combined sea heights between 5 and 7 feet. The sea height will
change little through the first half of the week increase slightly
the second half.
A north and a east swell prevail over the local area. The north swell
will decrease tonight before being re-enforced on Tuesday. This
morning the east swell is between 4 to 6 feet and the north swell
is around 2 feet. The east swell will change little through the
week. The north swell, as mentioned, will drop to one foot tonight
before increasing to two feet Tuesday. The north swell will
increase to 3 feet Tuesday night. Neither swell will become large
enough to produce hazardous surf.
A trade-wind disturbance is generating scattered showers and
thunderstorms just south and west of Kosrae and Pohnpei...but near
Chuuk this morning. Drier moderate to fresh trades follow behind
the showers with dry air at Majuro building in across Kosrae and
Pohnpei States. Scattered showers today at Chuuk will taper
tonight as the drier weather builds in there tonight. Another weak
trade wind disturbance will bring showers to Majuro late Tuesday
and head westward, bringing showers to Kosrae and Pohnpei on
Wednesday and Thursday, and to Chuuk on Thursday and Friday.
Trade wind swell and wind waves will maintain hazardous surf along
north facing reefs of Chuuk and Pohnpei through this afternoon. Surf
should subside below advisory levels by tonight. Surf at Kosrae will
remain hazardous along north and east facing reefs through tonight,
but could fall below hazardous levels on Tuesday. Stronger winds
will remain hazardous for small craft at Majuro today. ASCAT pass
still shows 15 to 25 knot winds in the region, particularly to the
northeast and east. Winds should subside by tonight.
A benign weather pattern is seen across Yap and Koror this
morning as mostly fair weather prevails in the region. A weak
disturbance will bring showers and isolated thunderstorms to Yap
and Koror on Tuesday and Wednesday. Fresh northeast winds will
build in over the region for the last half of the week. A near-
equatorial trough could develop by the end of the week and bring
more clouds and showers by the weekend.
Northeast swell has subsided enough to allow surf to fall below
advisory levels at Yap and Palau.