Tuesday 26th  SEPTEMBER 2017 PM.

Tonight  and tomorrow:

A weak band of clouds between Samoa and Fiji marked a surface trough as analysed on the surface streamline chart this afternoon. A surface to mid level ridge to the east directs a fresh east to northeast windflow  across the Samoa island chain. Patches of low level clouds caught up along the aforementioned flow are moving westward over the forecast zone and will the trigger for some tradewind showers. Observations from the wind profiler and sounding this afternoon support the low level moisture which is also evident on the satellite loop this afternoon.  Global models suggest drier conditions to persist through tomorrow with fresh east to northeast winds.  

THURSDAY THROUGH SATURday:

The aforementioned surface trough between Samoa and Fiji is predicted to move southeast slowly. A convergence zone is predicted to develop to the east of the aforementioned trough tomorrow evening. This CZ is expected to move over the forecast zone tomorrow night and will be the rainmaker for the long term forecast as it slowly make its way eastward. Anticipate isolated showers at the early part of the long term forecast, becoming scattered with possible heavy falls by Thursday night into early Friday. With fresh east to northeast winds.  Another high pressure ridge is predicted to enter the forecast zone by Saturday, and will re-introduced the tradewind regime across the island chain at the latter part of the long term forecast.   

MARINE

Aunuu wave buoy and altimeter observations recorded swell heights of 6-7feet, while wave-watch model suggest these swells to slowly developing and will  peak to near 9 feet by Thursday.

Warning/Advisories

SMALL CRAFT ADVISORY

wILSON

*******************************************************************************