Area Forecast Discussion
Issued by NWS Pago Pago

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
FXZS60 NSTU 240132

Area Forecast Discussion
National Weather Service Pago Pago  AS
232 PM SST Sat Sep 23 2017

.Short term...
TONIGHT THROUGH MONDAY NIGHT...Surface trough over the islands is
slowly moving south southwest. Midlevel ridge to the east of Manua
will continue to steer and push moisture south of the territory.
RAOB from this afternoon depicts a stable profile. A strong high
pressure approaching from the far southwest is migrating east and
will generate breezy east winds tonight. As the high moves south
of the islands, it will strengthen and escalate winds to strong
and gusty flow on Monday night. Models are also depicting
scattered showers to pass over the islands on Monday. Will amend
the previous forecast to reflect the new outputs. Expect isolated
showers tonight before becoming scattered on Monday only. Breezy
east winds will begin tonight before intensifying to strong and
gusty winds on Monday night.

.Long term...
TUESDAY THROUGH SATURDAY...The strong high pressure will will
continue to pursue east and therefore a gradual decrease of winds
to breezy flow on Wednesday afternoon. A col will move across the
islands on Thursday and thus further diminish winds to light and
variable conditions. Another high pressure propagating east will
again generate gentle trades on Friday. Most of the moisture will
be found to the south southeast on Thursday as the trough axis
pass over the islands.


Seas remain below advisory levels in the last several hours.
Currently winds are light and variable. Therefore will keep seas 5
to 7 ft tonight before rising 6 to 8 ft on Sunday morning. With
strong and gusty winds to start the new week, seas will rise 7 to
9 ft on Monday night. Seas are expected to drop below advisory
levels on Thursday morning.





Malala is the U.S. government's official web portal to all federal, state and local government web resources and services.