Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
123 FXZS60 NSTU 120107 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 207 PM SST Thu Sep 11 2025 .Short term... Satellite imagery has shown a trough remains just to the north of Tutuila and Aunu`u, but remained near the Manu`a region throughout the morning and early afternoon hours. However, this trough is expected to continue weakening throughout the overnight hours as a developing low pressure system near the Solomon islands region as it shifts the trough northward. By Friday morning, a strong low pressure system centered well to the south of American Samoa is forecast to shift drier air from the southwest into the region. This drier than average airmass is to remain over the territory through Saturday night to give partly cloudy skies with plenty of sunshine throughout the day. The risk of rainfall diminishes to isolated to scattered (20 to 30% chance) showers throughout this time. Winds are to become south/southeasterly and to decrease to around 10 mph. .Long term... A developing strong high pressure system over the Tasman Sea this weekend is forecast to move eastward early next week. This will position a trough that is to extend northward from the aforementioned low over the region. Increasing southeasterly winds from the high moving closer to the territory could reach up to 25 mph at times from early to mid week. At this time, the numerous showers (70% chance) forecast is not projected to produce flash flooding over the American Samoa islands. && .Marine... Rough seas remained today along the American Samoa coastal waters due to a fresh easterly breeze. Winds are forecast to decrease and to become south/southeasterly by Saturday. Therefore, seas are to ease tonight and Friday. By the weekend, sea heights are forecast at around 5 feet. The High Surf Advisory will likely expire tonight and the Small Craft Advisory as early as Friday morning. Ideal conditions are expected for mariners this weekend. && .PPG WATCHES/WARNINGS/ADVISORIES... A High Surf Advisory remains through tonight. A Small Craft Advisory remains through Friday. && $$ LaPlante