Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
172 FXZS60 NSTU 020005 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 105 PM SST Wed May 1 2024 .Short term... Satellite imagery this morning and early afternoon shows showers and thunderstorms from a trough currently to the east/northeast of American Samoa. To the south, a ridge of high pressure moves southeastward, further away from the region. This will allow the trough to move over American Samoa later today and tonight. The trough will bring plenty of moisture and instability into the region, which will allow thunderstorms to continue developing within the trough. Widespread showers are forecast throughout the region with scattered thunderstorms tonight. Recent ASCAT imagery shows stronger winds, compared to so far today, around 15 to 20 mph in the area of the trough. Winds will increase to that strength tonight may bring gusty winds with potentially heavy rainfall at times. Another ridge from the southwest will move closer to the territory from Thursday and Friday. This will slow down the movement of the aforementioned trough to remain over the region. Therefore, the forecast remains the same with widespread showers with a risk of thunderstorms during this time. Winds are expected to remain around 15 to 20 mph. .Long term... For the weekend, the trough is expected to move south. This will decrease winds to up to 15 mph. The risk of rainfall will reduce, from widespread to numerous (60% chance). Even though showers are likely, it would be in the passing form and gusty winds are possible when showers move through. Winds are forecast to reduce to light and variable with scattered passing showers (40% chance) for early next week as the trough continues to slowly move southward. && .Marine... Recent altimeter data and data from a drifting buoy to the east of the American Samoa islands shows seas between 7 to 9 feet where the trough is currently located. As the trough moves over the region, winds are forecast to increase to a fresh easterly breeze which will build sea heights over the American Samoa coastal waters to around 7 to 9 feet. The trough is expected to remain in the region through Friday, which will cause enhanced sea conditions to remain during that time. The trough is forecast to move south by the weekend. Wind driven seas will ease as winds will decrease to a gentle to moderate breeze to around 6 to 7 feet with the occasional 8 footers. && .PPG WATCHES/WARNINGS/ADVISORIES... A Small Craft Advisory remains in effect. && $$ LaPlante