TUESDAY 07th DECEMBER 2021 (AM SHIFT)
TODAY & TONIGHT:
A ridge of high pressure to the Northeast currently affects the group with a trough of low pressure which links to the low circulation located south of Southern Cooks with an active convective cloudband. Meanwhile, a speed convergence along the Northeasterly windflow is expected to descend over the islands by the evening. The surface to mid-level system is being enhanced along an area of instability and lifting mechanisms provided by fresh Northeast wind flow. Atmospheric conditions showed favourable conditions of free convections within the nowcast period coupled with the movement of the speed convergence to the Northeast and its associated moisture content would increase cloud cover and precipitation for the islands from the evening towards tonight. Therefore, expect increasing cloud cover, with scattered rain. Moderate to heavy falls with a few thunderstorms and gusty winds at times.
WEDNESDAY THROUGH MONDAY (06th – 12th DECEMBER)
The aforementioned speed convergence would continue to remain within the vicinity of the islands with scattered rain and fresh winds, due to a well-established ridge. Winds would increase from moderate to fresh Northerly before it passed southwestward. By Saturday a low-pressure system may develop to the south of the forecast zone near the Tonga group, forcing rainfall activities along with it while tracking south-eastward. Therefore, anticipate isolated to scattered showers with possible moderate to heavy falls in the next couple of days, easing towards the end of the week.
MARINE OUTLOOK (MONDAY 06th – SUNDAY 12th DECEMBER)
The recent observations show waves of 1.5 – 2 metres. However, the above-mentioned ridge is predicted to bring moderate to fresh Northerly winds towards the evening, generating high swells of more than 2.5 metres.
VALID : MARINE ADVISORY FOR NORTHERN MARINE WATERS OF SAMOA
WEATHER PM TEAM:
A. Maua, F. Kalapani & T.F Aumua