Strong and gusty trade winds expected through Thursday as a new high builds north of the state. Relatively dry conditions are expected today with windward and mauka showers tonight into Thursday as a band of moisture moves from north to south across the state. Moderate to locally breezy trades will briefly return around Friday or Saturday, but trade winds will strengthen once again Saturday night into Sunday.
A high building far north of the state will strengthen the trade winds and will bring windy conditions across the state. A Wind Advisory is in effect for the typical windy areas around Maui County and the Big Island until 6AM Thursday. Winds will be strongest through gaps, and over and downslope of ridges through Wednesday evening. Wind gusts of 50 mph are expected during this time. For Oahu and Kauai strong and gusty trades are possible but confidence was to low to include them in the wind advisory at this time. The combination of strong trade winds and mostly dry conditions will elevate fire weather concerns today.
A frontal boundary is expected to move north through south of the island chain tonight into Thursday, which should bring a brief increase of scattered showers, especially over windward and mauka areas. The strong trade winds should begin to ease some by Friday afternoon down to breezy to locally strong speeds. From Friday through the weekend, we should see our typical trade wind showers most frequent during the overnight and early morning hours over windward and mauka areas. Trade winds should restrengthen back to strong levels Saturday night into Sunday as another high passes far north of the state.
Locally strong trade winds are expected through tonight. Showers will continue to be carried in on the trade wind flow, and primarily impact the windward and mountain areas. Brief MVFR conditions are expected within showers while VFR prevails elsewhere.
AIRMET Tango will remain in effect for moderate turbulence downwind of terrain due to the breezy to locally strong trade winds. Expect this AIRMET to remain in place for the foreseeable future. Upper level turbulence is also possible over the state, however those conditions are expected to improve today.
AIRMET Sierra is in effect for mountain obscurations for windward areas of Molokai, Maui, and the Big Island. Conditions are improving for Molokai and Maui, and that may be dropped later this morning.
Strong high pressure north of Hawaii is producing fresh to strong winds across the marine areas this morning. Winds may be locally higher through the typical windier channels and waters near Maui County and the Big Island, for which a Gale Warning remains in effect through tonight. A Small Craft Advisory (SCA) remains in effect for all other coastal waters, and this may need to be extended into Thursday for most waters.
Seas are also forecast to exceed 10 feet later today into Thursday with the arrival of a large north-northwest swell. Meanwhile, a front will drop south from the northern offshore waters to reach the central waters as it weakens into a trough by tonight. The trough will bring increased shower activity to the area through Thursday. Winds will gradually ease through Saturday as high pressure weakens slightly, but this weekend another strong area of high pressure passes north of the islands, which may lead to another period of strong winds Sunday into early next week.
A large, long-period north-northwest swell (340 degree) swell arrives today and will bring rapidly increasing surf to north and west-facing shores. Surf will reach advisory level this morning and approach warning level surf tonight and linger into Thursday. A High Surf Advisory remains in effect for north and west-facing shores of Niihau, Kauai, Oahu, Molokai and for north-facing shores of Maui through Thursday afternoon. Surf will decrease Friday followed by a north swell this weekend which could push surf back to advisory levels on Sunday.
Surf along east facing shores will increase today as trade winds strengthen. East shore surf will remain elevated and choppy through Friday, then may diminish slightly this weekend. A small, long-period south swell may bring a small bump to south shore surf today into Thursday. Surf becomes tiny again Friday into the weekend for south- facing shores.
High Surf Advisory until 6 PM HST Thursday for Niihau-Waianae Coast-Oahu North Shore-Maui Windward West-Kauai North-Molokai Windward-Molokai North-Molokai West-Maui Central Valley North- Windward Haleakala.
Wind Advisory until 6 AM HST Thursday for Lanai Mauka-Kahoolawe- Maui Leeward West-Kohala-Molokai-Lanai Windward-Lanai Leeward- Maui Central Valley North-Maui Central Valley South-South Haleakala-Big Island South-Big Island Southeast-Big Island North.
Small Craft Advisory until 6 AM HST Thursday for Kauai Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters-Kauai Channel- Oahu Windward Waters-Oahu Leeward Waters-Kaiwi Channel-Maui County Windward Waters-Maui County Leeward Waters-Big Island Windward Waters.
Gale Warning until 6 AM HST Thursday for Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters.
