Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
881 FXHW60 PHFO 140133 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 333 PM HST Thu Jun 13 2024 .SYNOPSIS... High pressure will linger northeast of the Hawaiian Islands into next week, producing moderate to breezy trade winds. Weak upper level troughing will keep brief periods of windward showers in the forecast, favoring windward and mountain areas. Leeward locations will be drier, with the exception of the Kona slopes of the Big Island, which will see a few showers will developing each afternoon and evening. && .DISCUSSION... This afternoon, surface high pressure is centered northeast of the main Hawaiian Islands. Latest satellite and radar imagery shows scattered clouds moving into mainly windward and mauka locations with isolated light showers. In areas sheltered from the background trade wind flow, such as the Kona slopes of the Big Island, sea breezes have increased cloud coverage today. Afternoon soundings at Lihue and Hilo show stable conditions with strong inversions between 5,000 and 6,000 feet. The surface high will linger through this weekend and into next week. This high will maintain a fairly typical moderate to breezy trade wind weather pattern into the foreseeable future with little day-to-day variation. Weak upper level troughing will keep the trade wind temperature inversion heights between 5,000 to 7,000 feet for much of the forecast period. Expect brief showers at times, mainly over windward and mountain areas. Shower activity will trend higher in the overnight to early morning hours each day. Drier conditions are forecast over leeward locations. High level cirrus clouds will move over the state Friday into the weekend. Not much day to day change in the weather forecast is expected over the next seven days. A slight increasing trend in the easterly trade wind speeds may develop by Wednesday of next week. && .AVIATION... Moderate to breezy trade winds will persist over the next couple of days. Low clouds and showers will favor windward and mauka areas, bringing brief periods of MVFR conditions. A few showers may make it over to leeward areas at times, but otherwise, VFR conditions should prevail. No AIRMETs are currently in effect. However, AIRMET Sierra for tempo mountain obscuration may be needed tonight for a few windward areas across the island chain as low clouds and showers increase in coverage, particularly for the eastern end of the state. && .MARINE... Fresh to strong easterly trades will continue through the weekend as the surface ridge remains north of the area. This will support continuing the Small Craft Advisory (SCA) for the windier channels and waters around Maui County and the Big Island each day. Surf along south facing shores will hold steady this evening due to a mix of a fading south-southwest swell and a small, medium- period southeast swell. A fresh, long-period south swell will arrive later tonight into Friday, then peak late Friday into Saturday. This swell could produce near warning-level surf at its peak late Friday into Saturday, with advisory level surf likely mid-day Friday. A gradual downward trend is expected Sunday into early next week. After this swell moves out, very little swell is expected next week beginning around Tuesday. Surf along north- facing shores will remain up above the summertime average (flat) this evening as a short-period north- northwest swell moves through. A downward trend is expected Friday through the weekend. Surf along east-facing shores will remain small and choppy each day due to a limited trade wind fetch upstream of the islands. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Saturday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Vaughan AVIATION...Farris MARINE...Powell