Area Forecast Discussion
Issued by NWS
FXPQ60 PGUM 282142
Area Forecast Discussion
National Weather Service Tiyan GU
742 AM ChST Wed Mar 29 2017
.Marianas Synopsis...Fresh to strong trades are expected today
with seas 6 to 8 feet across the Marianas waters. A shear line
will move slowly south from north of Saipan with an abundance of
mainly high clouds over the region.
Once again, a relatively quiet and dry period is in store for the
Marianas. A shear line will slowly move southward and increase
clouds. A brief shower can not be ruled out, but guidance has been
consistent with substantial dry air aloft. Wind will gust up to
25 mph before decreasing into the 15 to 20 mph range tonight into
A small craft advisory has been issued for wind which will gust
around 25 kts today through Thursday and possibly into Thursday
night before decreasing. Additionally, seas which are already over
6 feet will continue to increase and will reach up to 9 feet by
tonight into Thursday and could locally hit 10 feet.
By Friday, both wind and seas will be decreasing and this trend
will continue into the weekend.
Confluence (streamlines flowing together, coming closer) of trade
winds is causing low-level convergence along a line in Eastern
Micronesia. This line includes Pohnpei and Kosrae but passes well
south of Majuro. A tropical disturbance spins up out of this over
the next few days, then moves westward. Showers will not be far
from Pohnpei and Kosrae the rest of the week although activity
levels should diminish after tonight, however Majuro looks
significantly drier. After this week, the band of convergence
lifts north and at that time it could affect Majuro and other
islands in the Marshalls.
Little change in sea heights is expected the next few days, then
over the weekend they will start to gradually diminish. The high
surf advisory at Kosrae should be able to come down Thursday
though. The swells are combining with king tides of up to 6 feet
to promote a risk of minor coastal inundation at Majuro through
this afternoon and at Kosrae through Thursday morning.
Chuuk is under the influence of the same convergence and emerging
tropical disturbance as Pohnpei. Around Thursday they should break
out of the showers, at least until the weekend. At Yap, the
disturbance should pass south while the shear line remains north.
The tropical disturbance should hit Palau, but will still be weak
when it does. The rain should diminish after Friday.
Combined seas will increase slightly through Friday, then start to
diminish over the weekend. They should peak below small craft
advisory criteria. Therefore no hazards are foreseen at this time.
Marianas Waters...Small Craft Advisory until 10 PM CHST Thursday