Light trade winds will produce rather dry conditions over most areas into tonight. Chances for heavy showers will increase during the day on Tuesday as developing low pressure and deep tropical moisture approach the islands from the southwest. The trough, or possibly a weak low, will pass over the island chain Tuesday night through Wednesday night, bringing the threat of heavy flooding rainfall and thunderstorms. The trough will weaken Thursday and Friday, though humid conditions with a chance of heavy showers may linger. Trade winds may briefly redevelop Saturday, though unsettled conditions could return Sunday.
Issued at 945 AM HST Mon Oct 26 2026 A gentle trade wind pattern is expected today with localized sea breezes developing across many leeward areas. An area of moisture lingering around the Big Island will bring some showers throughout the day today with periods of MVFR conditions possible mainly over windward Big Island. Otherwise, VFR conditions should prevail.
A band of deep tropical moisture will arrive from the southwest Tuesday and will likely bring periods heavy rain and isolated thunderstorms. MVFR to IFR conditions should be expected at many areas across the state starting as early as Tuesday afternoon and persisting into Wednesday.
No AIRMETs in effect, but we may need AIRMET Sierra for mountain obscuration over parts of windward Big Island later today.
Issued at 311 AM HST Mon Oct 25 2026 A surface low far northeast of the Hawaiian Islands will stall roughly 800 nm northeast of the state today. A low pressure trough is forecast to approach the area by late tonight and bring heavy showers with embedded thunderstorms to the waters over the next several days. Relatively weak wind flow will persist through the forecast period.
A short period north northwest swell will gradually lower today. Meanwhile, an overlapping, moderate, mid- period northwest swell is will build today and bring surf to near advisory levels along north and west facing shores through Wednesday. A small north northeast swell should arrive during the second half of the week.
Overlapping south-southwest swells will keep surf along south-facing shores to around seasonal averages through Tuesday. A larger south swell may push surf up to near advisory levels Thursday and Friday.
Surf along most east-facing shores will be small through early this week, but areas exposed to wrapping northerly swells will experience periods of moderate surf today. East- facing shores should also see a bump in surf if the north- northeast swell materializes during the latter half of this week.
Flood Watch from Tuesday morning through late Wednesday night for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Central Oahu-East Honolulu-Ewa Plain-Haleakala Summit-Honolulu Metro- Kahoolawe-Kauai East-Kauai Mountains-Kauai North-Kauai South- Kauai Southwest-Kipahulu-Kohala-Kona-Koolau Leeward-Koolau Windward-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward- Maui Central Valley North-Maui Central Valley South-Maui Leeward West-Maui Windward West-Molokai Leeward South-Molokai North- Molokai Southeast-Molokai West-Molokai Windward-Niihau-Oahu North Shore-Olomana-South Haleakala-South Maui/Upcountry-Waianae Coast-Waianae Mountains-Windward Haleakala.
Wind Advisory until 6 AM HST Tuesday for Big Island Summits.
