FXZS60 NSTU 220120 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 220 PM SST Sun Feb 21 2021 .Discussion... The active South Pacific Convergence zone (SPCZ) is lingering over the Samoan island chain, as seen on latest GOES-17 mesoscale this afternoon. The winds and rain as forecast for last night through this morning were more concentrated over Savaii as well as Manu`a Islands with minimal seen over the main island of Tutuila. Although Tutuila has yet to see the impacts as previously forecasted, model data are still consistent with bringing hazardous winds developing overnight through early Tuesday. We have a very difficult time with confirming the wind forecast by model data, as there are no observations available of the persistent convection brewing just off-shore the islands. However, the models coupled with satellite are our only tools. Both the GFS and ECMWF models are in agreement with persistent northerly 35 mph winds especially tonight through Monday. Even though these winds are mainly advisory level, the models show wind core at 850mb of about 45 mph moving over late tonight through early Monday morning. Along with the effects of our steep terrain, higher and frequent gusts will be felt across the islands, especially along south facing mountain slopes through Monday. This is the reason why we are issuing a high wind warning for American Samoa through Monday, likely early Tuesday morning if the SPCZ continue to move slowly south. The active SPCZ will bring continuous rainfall through at least midweek. With the slow movement of the SPCZ, the potential for flash flooding remains very high. && .Marine... Latest PacIOOS Aunu`u wave buoy show advisory level heights from the north reaching the territory`s northern shores. The observed values are higher than forecast values. Hence, we will maintain previous values which are higher than model output to account for the difference with observations. Furthermore, we have upgraded the gale watch to a warning, as these gales are occurring over surrounding waters. As aforementioned, these gales will remain over American Samoa waters through at least Tuesday morning, as the SPCZ moves south. Also, surfs will continue to increase to at least 16 feet through Tuesday morning, and will especially be evident across north facing shores, with possible coastal flooding. && .PPG WATCHES/WARNINGS/ADVISORIES... High Wind Warning is in effect Gale Warning is in effect for surrounding waters High Surf Advisory remains in effect Flash Flood Watch remains in effect && $$ ELM/TM