SYNOPTIC DISCUSSION
SATURDAY 23rd NOVEMBER 2024 AM Shift

TODAY:
The latest satellite image indicates that clouds and rain are developing north of Samoa, associated with a surface convergence zone. The surface system is currently supported by a weak upper-level divergence. This system is expected to move southward toward the islands, bringing wet and windy conditions for today. As a result, increased cloud cover and rainfall are anticipated, leading to the extension of the Heavy Rain Warning and Flood Advisory for all of Samoa. For today, isolated to scattered showers, brief heavy falls and thunderstorms with gusty winds to impact the group.

SUNDAY THROUGH THURSDAY:
Unstable and wet weather conditions are expected to persist through the weekend, with easing conditions likely at the start of the new week. Weather models indicate a  surface trough passage on Sunday, which will maintain similar conditions. These conditions are expected to shift southwest as a strong high-pressure system to the south extends over the region, bringing trade wind flow and minimal rainfall activity. Rainfall is predicted to return by the end of the outlook period, though confidence in this forecast remains low. In the upper atmosphere, models show no indication of an upper-level trough within the outlook period. Therefore, expect rainfall activity to east by either Sunday or Tuesday depending on the movement of the aforementioned system.

MARINE OUTLOOK:
Wave and swell heights continue to exceed the advisory threshold due to moderate to fresh easterly winds prevailing across all marine waters. This condition is expected to persist today but will likely ease by tonight towards tomorrow. Therefore, the Marine Advisory will remain in effect for all marine waters of Samoa.  

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ADVISORIES/WARNINGS:
HEAVY RAIN WARNING
FLOOD ADVISORY
MARINE ADVISORY

Weather Duty Team:
LMSA & NT