Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
631 FXZS60 NSTU 290027 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 127 PM SST Sat Jun 28 2025 .Discussion... Fair weather cumulus clouds passing over the territory today indicate stable weather conditions for American Samoa. This is supported by this afternoon`s 00Z RAOB observations which reveal a very dry and stable mid-level airmass. This dry airmass is forecast to stay in place throughout the forecast period keeping rainfall chances at isolated to scattered (20-40%). Any rainfall that does occur will likely be brief and passing in nature, as this pattern does not support deep cloud growth. Winds have been observed out of the east to southeast throughout the day, but remain light at below 10 mph. A high pressure system to the southwest will intensify and move closer to the territory, bringing a return to our seasonal trade wind flow regime pattern by increasing the southeasterly flow across the region. Trade winds are likely to reach 20 mph by midweek, with higher gusts possible. && .Marine... Wave heights have drastically outperformed model forecasts, with seas remaining around 9 to 12 feet throughout the day at Aunu`u buoy. These elevated seas are associated with a nearby southeast swell featuring long peak period times of around 12 seconds. This is maintaining large surfs that were determined to be near warning thresholds. Reports of debris on roadways resulting from these surfs led to issuance of a High Surf Warning. Latest observations show a potential subsiding trend in seas which aligns with model projections. Therefore, surfs are expected to return to advisory levels by tonight. Seas are expected to further subside into the new week to near the threshold for Small Craft Advisory. Seas will increase once again by midweek as a fresh to strong trade wind flow develops across the coastal waters. These wind driven waves will lead to rough seas and hazardous conditions for small craft. && .PPG WATCHES/WARNINGS/ADVISORIES... High Surf Warning Small Craft Advisory && $$ Barton/Meredith