Tuesday 30th May 2017 PM.
Tonight and tomorrow:
Windy condition continues to persist over Samoa due to a tight pressure gradient from a ridge of high pressure system building from far southeast. Latest satellite loops shows scattered low-level clouds riding along the easterly flow currently affecting the island with a massive cloud band to the north and embedded severe thunderstorms. Surface streamline analysis placed a ridge of high pressure system south ridging North-westward, directing strong easterly wind-flow over Samoa and a convergence zone further North associated with the aforementioned cloud band. Strong easterly flow was observer hourly throughout the today as a result of a tight pressure gradient located over Samoa as drawn by surface streamline analysis and was also recorded from AWS, radar wind profile and from the ASCAT swath this afternoon. Therefore, expect tradewind showers for Southern side, with partly cloudy skies and brief showers for Northern districts with few thunderstorms possible. Expect fresh to strong easterly wind to prevails over the group.
Thursday - Saturday:
An intense high pressure system to the southwest is expected to migrate eastward and will maintain trade-wind flow over Samoa in the early stage of the outlook period. Global models also pick-up a weak low level circulation to develop to the North of Fiji heading to the weekend, an associate convergence zone is predicted to enter our forecast zone by Saturday evening as it slowly sink south-eastward, brining cloudy condition with some showery activities. Therefore, expect an increase with the moisture content near the surface mainly by Saturday afternoon into Sunday.
Observations from Aunuú wave bouy this afternoon shows tradewind swells of 9-11feet over our coastal water. Wave-watch model keep this swell over our areas within the next 24hrs. Therefore advisory for small craft remains for Strong easterly winds and high swells.
WIND ADVISORY REMAINS FOR sAMOA
small craft advisory remains FOR ALL COASTAL WATERS.
M.A & A.N