Area Forecast Discussion
Issued by NWS Pago Pago
Issued by NWS Pago Pago
788 FXZS60 NSTU 290059 AFDPPG Area Forecast Discussion National Weather Service Pago Pago AS 159 PM SST Sun Apr 28 2024 .DISCUSSION... The latest satellite imageries continues to show stable conditions across the area, with open cell cumuli clouds moving over the islands. However, an active surface trough just north (oriented northwest to southeast) of Swains Island, clustered with heavy thunderstorm activity, and deeper convections continues to move further west-southwest. Model data shows this trough migrating southward throughout the week, increasing the potential for flash flooding conditions and potentially gusty winds. Upper air data from this afternoon shows stable conditions with an elevated potential for adverse conditions over the area. Therefore, expect scattered showers with gentle to moderate easterlies for tonight through Monday, numerous showers with possible thunderstorms, and moderate to fresh easterlies Tuesday through at least Wednesday. Long term model solutions show a mid-level low pressure system embedded within the aforementioned trough line, moving over the area by Thursday through the end of the forecast period. This feature will increase the potential for flash flooding conditions. Also, as the trough migrates southward, winds will turn northeast to north by Friday through the end of the forecast period. Thus, expect numerous to widespread showers with embedded thunderstorms and gentle to moderate north-northeast breeze for the majority of the week. && .Marine... Seas of 5 to 7 feet remains across the islands through at least Monday. This is further supported by the latest satellite swaths in the area, and manuable observations of current coastal water conditions. As winds are expected to increase to fresh breeze by Tuesday, seas will potentially build to advisory thresholds by this time frame. Models are showing seas gradually subsiding to below advisory levels by midweek when winds also decrease. These wind-driven waves will bring choppy conditions in the area. Additionally, potential thunderstorm activity associated with the expected trough to the north to move over the islands, may elevate seas and winds nearby. Otherwise, no other significant swell is expected for this forecast period && .PPG WATCHES/WARNINGS/ADVISORIES... NONE && $$ JTA