FXHW60 PHFO 250147 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 347 PM HST Wed Apr 24 2024 .SYNOPSIS... Breezy to locally strong trade winds will continue through the week, with clouds and showers favoring windward and mauka areas. Trades look to ease slightly this weekend as high pressure weakens to the north and low pressure develops to the far northwest. && .DISCUSSION... The latest satellite and radar imagery shows a long band of east to west-oriented low clouds and showers embedded in the trade wind flow moving into windward areas of the islands. The most widespread showers are currently affecting Oahu through Maui. Some showers are also making it over to leeward areas as well, due to the breezy trades. Expect this band of enhanced showers to sag southward overnight, bringing additional rainfall to windward areas of all islands into Friday morning. A high pressure system will continue to linger far northeast of the island chain through Friday, producing breezy to locally windy trades across state. Wind speeds may approach Wind Advisory thresholds in some wind-favored locations over Maui and the Big Island into Thursday, but keeping speeds just below advisory levels for now. This high will drift farther east Friday into the weekend, as a cut off low pressure system develops approximately 1000 miles northwest of Kauai. Global models continue to indicate the cut off low will remain too far northwest of the state to have much, if any, impact on the local island weather. However, expect winds to veer from a more east to southeast direction and decrease to more moderate speeds this weekend, with overall drier conditions. && .AVIATION... Breezy to locally windy trade winds will prevail for the next several days as a surface ridge remains to the north of the islands. Clouds and showers will continue to favor windward and mauka areas, with isolated showers reaching leeward areas during the overnight hours. Bands of moisture moving across the islands will continue to bring local MVFR conditions to windward areas this afternoon, with more widespread MVFR likely tonight. AIRMET Sierra for tempo mountain obscuration remains in effect for windward sections of Oahu and Kauai this afternoon. Expect AIRMET Sierra to expand to windward sections of the remaining islands tonight. AIRMET Tango for moderate low level turbulence downwind of the terrain for all islands remains in effect, with little change expected through the forecast period. && .MARINE... A 1030 mb surface high, located roughly 800 nm north northeast of the state, will slowly drift eastward over the next several days. This feature will help drive strong to locally near gale east northeasterly trade winds across the islands. By Friday, the high is forecast to weaken, as low pressure develops well northwest of Hawaii. In response, easterly winds will weaken to light to moderate. A Small Craft Advisory for all Hawaiian coastal waters has been extended through Thursday. Beyond Thursday, this hazard may need to be extended for some of the typical windier waters of Maui County and the Big Island. Surf heights will remain below advisory thresholds for all shores through the forecast period. A small, medium period northwest swell will fill in across the waters tonight and persist through Friday. Another small, medium period northwest pulse will enter the waters Friday night, peak Saturday, and subside Sunday. Expect these swells to produce small surf along north and northwest facing beaches. Persistent trades will bring choppy, rough surf all week along east facing beaches. By this weekend, weakening trades will allow this surf to lower. Small background southerly swell will lead to small surf along south facing beaches through the forecast period. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Thursday for all Hawaiian waters- && $$ DISCUSSION...TS AVIATION...Ahue MARINE...Vaughan/JT