Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
542 FXHW60 PHFO 020643 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 843 PM HST Wed May 1 2024 .SYNOPSIS... Trade winds will strengthen on Thursday and become breezy Friday through the weekend. Rainfall will favor typical windward slopes, with an increase in showers expected this weekend through the first half of next week as a disturbance aloft passes overhead. && .DISCUSSION... High pressure centered far northeast of the state and a trough just northwest of Kauai will maintain light to moderate east to east-southeast winds over the western half and moderate easterly trades over the eastern half of the state through tonight. For tonight, we should see fairly dry conditions with a few scattered over windward areas and isolated showers possible over leeward areas. As the trough weakens and shifts westward on Thursday, high pressure will build over the region and trade winds will strengthen. By Friday, breezy trades are expected across the state with locally strong trades over windier areas of Maui County and the Big Island. As the trades strengthen, showers will also increase primarily over windward and mauka areas. An upper level low approaching the state from the west this weekend, should help enhance the showers and will allow for brief downpours this weekend into early next week. Although details are still uncertain, windward and mauka areas could be come quite showery through early next week, especially the western end of the state where the best instability exists. && .AVIATION... Moderate E to ESE winds will gradually strengthen through Thursday. SHRA and isol MVFR conds expected windward and mauka locations. VFR conditions will prevail leeward, except for isolated areas of MVFR conds over leeward Big Island in the afternoon and evening. No AIRMETs are posted, but increased low-level turb to the lee of the terrain is expected by Thursday, likely prompting the issuance of AIRMET Tango. && .MARINE... High pressure far northeast of the state will shift south through the rest of the week and dissipate as another high pressure builds to the north. A weak trough northwest of the state will begin to move far west of state over the next few days. In response, moderate to locally strong east-southeast winds will become more easterly overnight into Thursday. These easterly trade winds will then strengthen to fresh to locally strong Friday and hold into early next week. A Small Craft Advisory (SCA) remains in effect for typical windy waters around the Big Island and Maui through Thursday. This advisory will likely be expanded to include additional waters in the next package. Tiny surf will persist along north and west facing shores through Friday. A small, long period northwest swell is expected to fill in Friday night and peak Saturday, bringing small surf along north and west facing shores. Another small, long period northwest swell will fill in late Sunday, maintaining small surf along north and west facing shores into early next week. Small background south swells will continue through Saturday, providing tiny surf for south facing shores. A small, long period south swell may fill in over the weekend providing a boost in surf along south facing shores into early next week. Small, choppy surf along east facing shores will gradually become rough and choppy Thursday into early next week as trades return. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Thursday for Pailolo Channel- Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Ahue/Kino AVIATION...Walsh MARINE...Almanza