textproduct: Honolulu

SYNOPSIS

Trade winds will steadily strengthen through Thursday and could produce advisory level winds by Thursday afternoon, especially over Maui County and the Big Island. Passing showers will continue to ride in with the breezy to windy trade winds through early next week, primarily during the nights and early morning hours across windward and mauka areas.

SHORT TERM UPDATE

Trade wind showers were seen in the usual locations this morning, meaning mainly windward and mauka, with precipitation amounts ranging from a few hundredths up to around 3/4 of an inch in some higher elevations. Skies were partly to mostly cloudy. Today should play out like a typical trade wind day, with a slight increase of winds as the day progresses. This is well-handled by the current forecast and no changes are planned at this time.

PREV DISCUSSION

Issued at 343 AM HST Wed May 20 2026 This morning's radar and satellite imagery shows scattered showers riding in with the breezy trade winds mainly over windward and mauka areas. As we go through the day today and into tonight, trade winds will steadily strengthen and a drier air mass will move over the state. With the drier air mass in place by Thursday, showers will remain on the lighter side, but we should continue to see scattered showers over windward and mauka areas.

As the drier air mass moves in on Thursday, the inversion will lower and strengthen, which will result in some gusty winds over and lee side of terrain. Winds are expected to reach advisory thresholds on Thursday for the windier areas around Maui County and the Big Island, where gusts of up to 50 mph will be possible. For Oahu, wind gusts should be slightly weaker but gusts of at least 40 mph should be expected for areas downwind of terrain by late Thursday.

For the weekend, windy conditions will likely continue through Saturday. Trade winds could drop a notch on Sunday, but nonetheless breezy to strong trades will likely continue through early next week. Passing showers will continue to ride in with the strong trades from time to time and will mainly be focused over windward and mauka areas.

AVIATION

Fresh to strong trades will increase over the next 24 hours, becoming locally windy by Thursday as the atmosphere stabilizes. AIRMET Sierra is in effect for mountain obscuration across most windward areas due to MVFR conditions produced by a narrow band of showers moving across the state this morning. Expect improvement this afternoon. AIRMET Tango is in place for low level turbulence over and downwind of terrain. With winds building and stability increasing, this AIRMET will remain in place for at least the next couple of days.

MARINE

The high pressure ridge north of the Hawaiian Islands will strengthen over the next few days, resulting in trade winds increasing into the strong to gale range from Thursday into early Friday morning. A Gale Watch remains in effect for the Alenuihaha and Pailolo Channels. A Small Craft Advisory (SCA) remains in effect and will expand to all island waters by Thursday. Expect SCA to continue into the first half of next week.

Small, short- to medium-period north-northwest (330 degree) swell energy will decline through Thursday. The next small north- northwest (330 degree) swell will move into the Hawaii region on Saturday increasing surf heights along north- and west-facing shores through the weekend.

A series of small, long-period south swell energy supports near- average surf along south-facing shores over the next seven days. Meanwhile, strengthening trades maintain elevated surf along east-facing shores into next week.

HFO WATCHES/WARNINGS/ADVISORIES

Small Craft Advisory from 6 PM this evening to 6 AM HST Friday for Kauai Channel-Kauai Leeward Waters-Kauai Northwest Waters- Kauai Windward Waters-Oahu Windward Waters.

Small Craft Advisory until 6 AM HST Friday for Big Island Leeward Waters-Big Island Southeast Waters-Big Island Windward Waters-Kaiwi Channel-Maalaea Bay-Maui County Leeward Waters-Maui County Windward Waters-Oahu Leeward Waters.

Small Craft Advisory until 6 AM HST Thursday for Alenuihaha Channel-Pailolo Channel.

Gale Watch from Thursday morning through late Thursday night for Alenuihaha Channel-Pailolo Channel.