Moderate trades will strengthen to moderate to breezy Wednesday and hold into the weekend. Moisture will increase across the state from east to west today through Friday increasing chances of showers mainly for windward and mauka areas. Chances of heavy rain and flood potential for windward areas looks to develop Thursday through Friday as an upper level disturbance moves overhead. Drier air will move back in this weekend as trades continue. Moisture from the remnants of Tropical Depression 15-E may bring another round of enhanced showers early next week.
No major changes to the forecast as moderate trade winds prevail this morning. The trade winds will gradually strengthen to become locally breezy this afternoon into the evening. Moisture will continue to gradually increase as well throughout the day and increase windward cloud and shower coverage as it passes through. MVFR conditions will be possible in passing showers. Otherwise, VFR conditions will prevail.
AIRMET Sierra is in effect for tempo mountain obscuration for windward areas of the Big Island through Oahu and may be needed through the morning hours as showers linger.
Issued at 323 AM HST Tue Sep 15 2026 Moderate to locally fresh trade winds will persist today as a weak trough lingers to the northeast. By Wednesday, high pressure building north of the islands will increase the trade winds into the fresh to locally strong range through the weekend. Also by Wednesday afternoon, the remnants of Norbert will begin to move into the offshore waters as a trough and increase shower coverage as it traverses east to west across the islands, potentially through the weekend.
A series of long-period south to southwest swells will fill in through the week, leading to a gradual increase in surf for south-facing shores through the week. The first pulse fills in today into Wednesday out of the southwest, followed by larger south-southwest swells Friday into the weekend. Small surf is expected through Wednesday, after which an upward trend is expected, and surf could approach advisory thresholds by this weekend.
Surf along east-facing shores should see a gradual increase this week as trade winds strengthen and a small, medium-period east swell from Tropical Storm Norbert arrives. Flat to tiny surf along north facing shores is expected through the forecast period.
None.
