Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
672 FXZS60 NSTU 280035 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 135 PM SST Mon May 27 2024 .DISCUSSION... Hourly observations throughout the day reported partly cloudy skies with brief passing showers across the territory. Also observed over the area are high temperatures reaching 90 degrees. However, on the latest satellite imageries, a trough to the south and west looks to be migrating closer to the islands with severed parts of the trough moving over the territory. These parts of the trough will likely bring scattered to numerous showers for tonight only. Upper air observations (RAOB) from this afternoon (28/00Z) shows a conditionally stable atmosphere. Given the latest RAOB data and the close proximity of the trough, the potential for convections to build and prevail over the islands remains high. Model data on the other hand shows the aforementioned trough being pushed by a broad and strong high pressure system to the south- southwest as it migrates eastward throughout the week. This same high pressure system will produce fresh trades potentially increasing to gale force winds by Friday. By Tuesday night through the end of the forecast period, the trough will have remained over the territory and produce numerous to widespread showers with embedded thunderstorms. Thus, expect scattered showers with gentle to moderate easterlies for tonight through midweek, increasing to numerous showers and fresh trades by Thursday. Winds are expected to reach wind advisory thresholds with an incrase potential for flash flooding conditions by the end of the week. && .Marine... Combined seas of 4 to 6 feet continues to linger in the area through tonight. However, model data shows the aforementioned high pressure system generating a large swell from the south, building to advisory thresholds by Tuesday night through the rest of the forecast period. Swells with a far fetched area (long periods) will likely produce higher surfs and strong rip currents closer to shore. Additionally, trade winds are expected to gradually increase to near gale strengths by Thursday night into the weekend. These winds will also enhance seas and surfs even further. Therefore, expect rough seas to remain over the area for the majority of the week starting Tuesday night. && .PPG WATCHES/WARNINGS/ADVISORIES... NONE && $$ JTAllen