textproduct: Honolulu

SYNOPSIS

A weak surface trough will gradually move east to west across the islands tonight through Saturday, resulting in relatively light winds and a combination of trade showers and sea-breeze showers (during the afternoons). As this trough dissipates, trades will build in stronger Saturday night through Sunday, and even stronger trades are forecast for next week from Tuesday onward.

SHORT TERM UPDATE

Minor updates were made to PoP otherwise previous forecast remains on track.

PREV DISCUSSION

Issued at 339 PM HST Fri May 8 2026

Radar show showers, mainly windward and mauka, over Kauai and Niihau this afternoon. An increase in showers across the Big Island is expected soon, and is likely also on windward (northeast) Maui and Molokai. Satellite indicates low clouds over or near the higher terrain on each island, along with wispy high clouds streaming in from the southwest. These higher clouds should continue through the night, while the lower clouds will diminish in most areas after sunset.

A weak surface trough was located between Maui County and the Big Island as of 3 PM HST this afternoon. This feature will slowly drift westward, reaching Kauai Sunday. Trade winds will build in behind this trough, moving in from east to west through this weekend. Wind speeds will initially be light to moderate, but will become moderate to occasionally breezy early next week. This trough will keep winds weak enough to allow for sea-breeze showers to occasionally develop over leeward areas, even as trade winds build in and bring their typical windward-focused showers.

While that is occurring at the surface, the flow aloft will change significantly. We will transition from weak troughing to our north this weekend to the rapid development of a closed ridge to our northwest by Monday. This ridge will become elongated along an east-west axis and remain with us all next week. Its presence will keep a surface ridge in place, allowing the trades to blow at least through the end of next week, and likely longer. This means trade wind showers, mainly windward and mauka, will be the rule for quite a while. There will be occasional fluctuations in available moisture throughout this period, and these will result in periods of enhanced shower activity from time to time. The timing is impossible to nail down more than a few days in advance.

AVIATION

Light to moderate trades gradually return tonight, becoming locally breezy tomorrow morning and persisting through the next several days. Expect cloud and shower activity to develop along the typical windward and mauka areas, resulting in periods of MVFR conditions. Otherwise, VFR conditions will prevail.

AIRMET Sierra remains in effect for mountain obscuration over Kauai due to lingering showers. There will be consideration for AIRMET Tango for low-level turbulence as trades gradually return.

MARINE

A high pressure ridge will remain in place north of the islands with gentle to fresh trade winds for most coastal waters with periods of strong trade winds developing over the windier waters and channels near Maui and the Big Island from Sunday onward. A Small Craft Advisory may be needed for these windier waters by Saturday night.

A declining moderate, medium-period, northwest swell will continue to bring elevated surf to north and west facing shores tonight. This swell and associated surf will slowly fade through the weekend. A new small, medium period northwest swell arrives on Saturday, leading to a small bump in north and west shore surf on Sunday. For the first half of next week, surf will be small with the lack of any significant northerly swell energy.

Background long period swell energy will keep small surf along south facing shores.

Surf along east facing shores will remain below normal this weekend, but will gradually increase through next week as trade winds gradually strengthen.

HFO WATCHES/WARNINGS/ADVISORIES

None.