Marine Weather and Tide Forecast for Poipu, HI

SHORT TERM UPDATE

Issued at 856 PM HST Sat Apr 18 2026

No changes made, previous forecast is on track.

AVIATION

Light to moderate easterly trades among some land-sea breezes will remain in place through the weekend under high pressure well north of the Hawaiian Islands with a surface trough lingering to the west. Overall, expect VFR conditions to prevail across most terminals through the period.

No AIRMETs in effect.



MARINE

A high pressure system far north of the state will slowly drift eastward this weekend. Easterly trade winds diminish tonight as a trough to the northwest of the islands develops into a weak low pressure system by Sunday. The resulting weakness in the ridge causes winds to veer southeasterly and diminish over the western Hawaii region from Sunday into early next week. Late next week, east to northeasterly trade winds begin to redevelop with weak ridging re-establishing north of the islands.

A small pulse of medium period swell energy from the northwest should produce a slight bump in north facing surf heights tonight into Sunday morning. A small to moderate, medium period northwest swell will move into the region by Monday night and continue through Wednesday. A moderate, medium period northeast swell arrives Tuesday and peaks on Wednesday, bringing moderate surf to north-facing shores, before slowly declining through the end of the week.

A medium-period south swell will continue to fade tonight, allowing surf along south shores to return to background levels by Sunday. A series of overlapping small south swells will move into the region into next week. Surf heights along east-facing shores remain on the smaller side due to weaker trade winds until the arrival of the aforementioned northeast swell on Tuesday. Small background energy from the west will be possible, especially later in the week, from Severe Tropical Storm Sinlaku.

HFO WATCHES/WARNINGS/ADVISORIES
None.