SYNOPTIC DISCUSSION
SATURDAY 21st MARCH 2026 AM SHIFT

TODAY INTO TONIGHT:

In the southwest pacific region, the active SPCZ continues to remain to the west with major accumulated rainfall and thunderstorms. This synoptic settings is mainly because of the persistence of the easterlies across the area of concern, with periods of patches of low-level cumulus congestus. The radiosonde profile depicted abundant low-level moisture content, deepening mean wind flow, and weak-to-moderate instability. On that note, water vapor channels collectively indicated mid-to-upper level moisture. Coincidently, present weak wind shear environment this support vertical cloud formation with negative cyclonic curvature. Henceforth, late morning through noon, the current satellite data showcase developed convective clouds with showers and possible thunderstorms, as the diurnal weather patterns slowly kicks in. Expect this weather condition may persist through the evening and at night time.

SUNDAY THROUGH FRIDAY:

The model consensus, generally showcase that the easterlies with brief showers is forecasted to persisted throughout the area of forecast until the mean wind flow steadily swerve to the northeast with moisture content on Monday through Tuesday in the new week. Then on Wednesday, where an intensified area of high pressure to the east of New Zealand slowly move to the east. Thus, the wind strength may weakening which could become light and variable while steadily becoming west-to-northwest on Thursday through Friday, hinting a weak convergence zone with a low probability of severe weather condition.

MARINE OUTLOOK:

The latest observed marine data continues to revealed wave and swell heights across Samoa’s marine waters are still below the 2.5 metres threshold value, which poses no threat. Wave models suggest this trend is expected to persist throughout the forecast period.

ADVISORIES/WARNINGS:
NONE

Weather Duty Team:
A. Liu, A. Sofeni, C. Baker, & A. Uili.