Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
941 FXHW60 PHFO 131948 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 948 AM 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 showers will developing each afternoon and evening. && .DISCUSSION... Surface high pressure centered northeast of the main Hawaiian Islands 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 time, mainly over windward and mountain areas as the trade winds lift the moisture 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. AIRMET Sierra for tempo mountain obscuration is in effect for windward portions of the Big Island through Oahu. Conditions should improve by this afternoon. AIRMET Tango for tempo moderate low level turbulence lee of island terrain may be needed sometime today as winds below the inversion approach 25 knots. && .MARINE... Fresh to strong easterly trades will continue through the weekend, as the surface ridge remains north of the area. This supports the Small Craft Advisory (SCA) continuing for the windier channels and waters around Maui County and the Big Island each day. Surf along south facing shores will hold steady today due to a mix of a fading south-southwest swell and a small, medium-period southeast swell through Thursday. A fresh, long-period south swell is expected to arrive tonight into Friday, then peak late Friday into Saturday. This swell could produce near warning-level surf through its peak late Friday into Saturday. 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) today as a short-period north- northwest swells move 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