textproduct: Honolulu

SYNOPSIS

Moderate trades hold through today. A sea breeze pattern then develops for the midweek period followed by returning light trades. Limited rainfall during this time.

SHORT TERM UPDATE

Stable moderate trades in place with a rather flat inversion at 7000. Mid and upper levels are particularly dry and stable today per this morning's soundings out of Lihue and Hilo. No meaningful weather anticipated as some trapped boundary layer moisture delivers light showers windward and mauka today into tonight.

PREV DISCUSSION

Issued at 320 AM HST Mon May 4 2026 Moderate easterly trades will remain in place today, with low clouds and a few light showers focused over windward and mauka areas. Leeward areas will remain mostly dry, with only isolated passing showers possible.

Beginning Tuesday, the ridge north of the islands will weaken in response to a series of cold fronts passing well north of the state. This will lead to a gradual easing of the trade winds, with local land and sea breeze circulations becoming more dominant through midweek. From Tuesday through Thursday, a more humid air mass will settle over the islands, with dewpoints potentially climbing into the mid- to upper-60s. These dewpoints combined with the afternoon sea breezes will support localized afternoon cloud buildups and a few brief showers over interior and leeward areas, followed by clearing at night as land breezes develop.

By the latter part of the week into the weekend, moisture and rainfall chances may trend up. Global guidance indicates upper heights lowering as an upper-level disturbance approaches the region. In addition, a weak attendant frontal boundary may move into the area. However, there remains considerable spread among the model solutions regarding the timing and strength of these features, so confidence in the details remains limited at this time.

AVIATION

Moderate trades continue through today, with clouds and brief showers expected over windward sites. Periods of MVFR ceilings and visibility are possible in showers, otherwise widespread VFR is expected. Trades are expected to begin weakening tomorrow, allowing land and sea breezes to occur.

No AIRMET's are currently in effect, but mountain obscurations over windward areas are possible later today due to upstream showers.

MARINE

Issued at 320 AM HST Mon May 4 2026 Moderate to locally fresh trade winds will be in place today and then weaken to land/sea breezes Tuesday and Wednesday as a front to the northwest passes by to the north and weakens the ridge. Gentle to moderate trade winds are expected to redevelop Thursday and Friday before another front passes by to the north this weekend and make winds light and variable.

A moderate northwest swell coming in a little below guidance will build today and produce surf above seasonal average during the peak tonight and early Tuesday. This swell will slowly decline late Tuesday and Wednesday. A larger northwest swell could produce surf near the High Surf Advisory level Thursday, then lower Friday into next weekend.

A south-southwest swell will gradually decrease today and Tuesday, with small pulses keeping surf from going flat for the later half of the week.

Trade wind swell will lower below seasonal average today and will

HFO WATCHES/WARNINGS/ADVISORIES

None.