Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
044 FXZS60 NSTU 250058 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 158 PM SST Fri May 24 2024 .DISCUSSION... Cloud coverage throughout the day reported mainly mid to upper level clouds with a light to gentle easterly breeze, associated with a ridge over the area. The latest satellite imageries together with the upper air data from this afternoon (25/00Z) confirms these conditions as a dry air mass lingers over the territory. However, the latest model data shows a weak surface trough to the east moving over the area by overnight tonight into Saturday morning. This trough is expected to bring scattered to numerous showers, and not reach flash flooding criteria for this time frame. Model data is showing a dry air mass following the aforementioned surface trough, bringing less moisture for the rest of the short term forecast period. Once the surface trough passes the area, expect scattered showers with a gentle easterly breeze for the rest of the weekend into the new week. As the new week progresses, model data is showing a boundary layer moving closer and over the area by at least midweek. This feature will likely bring adverse weather conditions for this time frame. Winds will also remain gentle turning southeast towards the end of the long term forecast period. Therefore, expect scattered showers for the new week, increasing to numerous showers by midweek into the rest of the week. Winds will also remain at gentle to moderate from the east for the majority of the new week, turning southeast on Thursday. && .Marine... Calm and serene conditions has been observed across the American Samoa shorelines in the last 24 hours. These observations are futher supported by the latest satellite and model data. Combined seas of 5 to 7 feet will remain across the coastal waters tonight through Saturday. Seas are expected to remain below the advisory thresholds through at least early Tuesday. These conditions also conincides with the light and gentle easterlies for the time frame. However, model data is showing a long period (>15 sec) south swell moving into the area by Tuesday. This large swell is expected to enhance seas and surfs starting Tuesday through the end of the forecast period. Also a reminder, long periods can generate strong rip currents underwater and much higher surfs closer to the shorelines. Thus, will continue to monitor conditions for any changes in the forecast. && .PPG WATCHES/WARNINGS/ADVISORIES... NONE && $$ JTAllen