Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
786 FXZS60 NSTU 110109 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 209 PM SST Thu Jul 10 2025 .DISCUSSION... Much cooler temperatures have been observed at the station within the last 24 to 36 hours with the daily high temperatures in the lower 80 degrees. This is due to cooler air transported from the south by a high pressure system to the south. Also, held by the high pressure system just north of the territory, is a trough weakening as shown by the latest satellite imageries. Dry air pockets within the weaker portion of the trough have kept the deeper convections away from the islands throughout the day. Hence, the little to no showers observed and the significant drop in flash flooding threat compared to the last couple of days. Model data shows the aforementioned trough further weakening as a high pressure system to the south holds moderate to fresh east- southeast winds over the islands, peaking at strong winds over the weekend. No threat of wind advisory conditions is expected for this time frame. However, the threat of embedded showers within the wind flow may pose a minor risk of ponding and runoffs from time to time in low-lying and vulnerable locations. Also, showers may be heavy at times, but very brief. The long term model data shows another high pressure system following the current high pressure to the south, continuing to produce fresh easterlies for the new week. These winds will likely keep the brief passing showers over the territory, with much cooler temperatures. Expect breezy with scattered to numerous showers for the rest of the forecast period. && .Marine... Manual observation of seas from the WSO Pago Office show heights well below advisory thresholds. This is further supported by data from the PacIOOS buoy near Aunu`u (east of Tutuila Island) with heights around 6 to 7 feet and peak periods around 10 to 12 seconds long. These parameters translates to surfs around 7 to 9 feet. Meanwhile, data from the PacIOOS buoy near Poloa (west-King Poloa) show heights around 5 to 7 feet. Although seas and surfs are below advisory criteria, model data shows an upward trend as trade winds are expected to also increase to a fresh breeze by Friday. Combined seas of 8 to 10 feet is projected to peak at least 12 feet by the weekend. Thus, the advisory for small crafts will continue to remain for the rest of the forecast period. Higher than normal surfs may also be observed at some shorelines, along with strong rip currents, especially during tide transition times. Will continue to monitor and update forecasts as more data becomes available. && .PPG WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory && $$ JTAllen