SYNOPTIC DISCUSSION
FRIDAY 06th MARCH 2026 AM SHIFT

TODAY INTO TONIGHT:

As of now, the trough of low pressure closely located to the east of Samoa, with associated clouds and showers slowly moving over the area of responsibility. The radiosonde profile, indicated abundant low-level moisture content and instability. Interestingly, the relative vorticity field at the (850-700) hPa showcased a low-to-moderate negative cyclonic anomalies, hinting the severe system’s movement and location. What’s more, expect diurnal weather patterns contributes to the synoptic lifting mechanisms. Hence, anticipate heavy downpours in some areas and a few thunderstorms. There’s a moderate-to-high chance this severe weather system persist across the area of responsibility through tonight into tomorrow. For that reason, the heavy rain advisory remains in effect for all land areas of Samoa.

SATURDAY THROUGH WEDNESDAY:

Through model consensus, evince the synoptic rain-maker system may continue to provide accumulated rainfall and thundery activities at least late Saturday. At the same time, a surface-to-mid-level ridge migrated from the northeast on Sunday, causes the previously stated severe weather system descends southward. This reduces daily precipitation for the start of the new week as trade wind showers are forecasted to impact our islands. A strong Easterly wind flow [20-25 knots] anticipated at the steering level during mid-week and will likely increase the chance for periods of heavy falls and gusty winds through the latter days of this outlook period. TPW and streamline model runs indicate the conditions mentioned above particularly for the lower to mid atmospheric level. We’ll continue to monitor observations and provide advices where possible if predictions remain for the next few days.

MARINE OUTLOOK:

The latest marine observations from Aunu’u, King Poloa wave buoys and altimeter data indicate that the wave and swell heights fluctuate at 2 meters, suggesting no imminent threat across Samoa’s marine waters. Global wave models suggest that wave activities will persist below the advisory threshold of 2.5 metres throughout this outlook period.

ADVISORIES/WARNINGS:
VALID: HEAVY RAIN ADVISORY

Weather Duty Team:
A. Liu, L. I. Tuatipi, C. Baker, & F.U. Namulau’ulu.