A high pressure system will linger north to northeast of the Hawaiian Islands through the middle of next week, producing moderate to breezy trades with minor fluctuations in speed. Brief increases in showers, most noticeable tonight and Sunday night, will give way to drier trades for most of next week. There is still significant uncertainty in next weekend's weather.
Breezy trades will persist through the forecast period. Isolated to scattered showers will mainly be confined to windward and mauka locations. Some of the shower may produce brief periods of MVFR ceilings and visibility.
AIRMET Sierra may be needed later tonight to account for mountain obscuration along selected windward areas due to low clouds and showers.
AIRMET Tango remains in effect for for tempo moderate turbulence downwind of terrain below 9000 ft.
Issued at 346 PM HST Sat Oct 17 2026 High pressure north of the islands maintains fresh to strong trades well into next week. The Small Craft Advisory (SCA) has been expanded in coverage to include Oahu and Kauai waters as trades are forecast to strengthen modestly tonight and tomorrow.
A mix of short period NNW swell which peaked at the outer buoys early this morning, and declining mid- long period swell (12 to 16 seconds) will keep small surf in place through tomorrow. Both of these swells drop off by Monday, allowing surf to drop to tiny levels through much of the week before a small northwest arrives towards the end of the week.
A mid to long period south-southwest swell (15 seconds) will keep above average surf in place tonight over south shores, then decline tomorrow and remain small through much of the week with background south swells. A small long period swell is possible next weekend.
Rough trade wind swell will produce above average surf for E shores through Tuesday before declining with weakening trades mid- week. Expect some wrap of NNW swell for exposed shorelines through tonight.
Small Craft Advisory until 6 AM HST Monday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Kaiwi Channel-Kauai Channel-Kauai Leeward Waters-Kauai Northwest Waters-Kauai Windward Waters-Maalaea Bay-Maui County Leeward Waters-Maui County Windward Waters-Oahu Leeward Waters-Oahu Windward Waters-Pailolo Channel.
