Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
612 FXZS60 NSTU 170058 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 158 PM SST Wed Jul 16 2025 .DISCUSSION... Model data and satellite imageries together with upper air observations (RAOB) from this afternoon (17/00Z) shows stable conditions remaining over the islands. A high pressure system to the south continues to generate gentle to moderate east-southeast winds for the remainder of the day, and will likely remain for the rest of the week into the new week. This high pressure system will also hold an active surface trough to the north (over Swains Island) of Tutuila and the Manu`a islands for this forecast period. Thunderstorms embedded within this trough will likely produce gusty winds and heavy showers near and over the Swains Islands area. No threat of flash flooding is expected for Tutuila and the Manu`a islands for tonight through at least Monday, only brief passing showers embedded within the wind flow. Long term model data shows a trough to the northeast moving into the area as early as Monday. This trough is expected to increase the potential for showers for the beginning of the new week. Expect moderate east winds to turn northeast by Tuesday. No other significant weather pattern is expected for this time frame. && .Marine... Ocean conditions remain rough for the southwest to west facing shores of the islands throughout the day. Long periods around 14 to 15 seconds indicate an enhancement of surfs closer to shore, and the high risk of dangerous rip currents. Model data show these conditions remaining throughout the forecast period, with fluctuations in periods from time to time. Although periods will be more than 10 seconds long for the most part of the forecast period (5 days out), sea heights are expected to subside to more favorable heights (<8 feet) starting Thursday through the end. Moderate east winds are also expected to linger over the area through the weekend. Thunderstorms embedded within an active trough to the north will continue to elevate seas and winds in the Swains Island area. The advisories for high surfs and small crafts remains in effect. && .PPG WATCHES/WARNINGS/ADVISORIES... High Surf Advisory Small Craft Advisory && $$ JTAllen