SATURDAY 24thMARCH 2018 AM;
TODAY & TONIGHT:
Further West of Samoa lies TD 11F with a high probability of evolving into a Tropical Cyclone for which it will not affect Samoa at all. A ridge of high pressure lies dormant within the vicinity of the Samoans islands thus providing cool Trades. Surface observations show light winds observed throughout the country. A short wave trough of low pressure lies further Southwest from Samoa. TD 11F will act as a steering mechanism that’ll introduce the trough later tonight for Samoa. Moisture availability within the atmosphere deepens. Satellite show deep convections just to the Southwest which correlates with location of the short wave trough. A broad area of low pressure lies in the mid-levels of the atmosphere and ascending over to the 250hPa level an strong divergence exist to the South of the islands thus enhances the surface mentioned system. For today expect generally fine weather with partial cloudiness and thunderstorms, but for tonight marking the arrival of the trough expect skies to become cloudy in the evening with isolated showers and possible thunderstorms.
SUNDAY TILL FRIDAY:
On a larger picture, the short wave trough will remain over the islands until Sunday evening. By Tuesday a convergence zone which links to the TD 11F will provide isolated showers in the remainder of the outlook period.
Altimeter readings together with observations from Aunu’u wave buoy provide observations of wave-heights averaging at 5-7 feet. Model predictions thus reveals the slight increase by Monday on the arrival of Northerly swells. Will monitor these situations and update accordingly.