Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
263 FXHW60 PHFO 161316 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 316 AM HST Sun Jun 16 2024 .SYNOPSIS... Breezy trade wind conditions will persist through the week. Clouds and showers will predominantly favor windward and mauka areas overnight into the morning as areas of moisture move through. An increase in windward shower coverage is possible from late Monday through midweek due to an upper disturbance drifting westward across the state. Some of these showers may briefly extend to the dry leeward areas of the smaller islands. && .DISCUSSION... Guidance remains consistent, showing a strong surface ridge north of the state throughout the week, possibly strengthening later on. This will sustain breezy easterly trade winds with clouds and mostly brief showers favoring windward and mauka locations. The trade wind inversion will be situated between 6,000 and 7,000 feet, and precipitable water (PW) levels will generally range from 1.0 to 1.25 inches. Rainfall amounts will remain limited, even in windward areas, except possibly during the first half of the week when an upper-level low drifts westward across the state, drawing up more moisture. Guidance indicates PW values increasing starting Monday night through Tuesday in the eastern part of the state, and later spreading to the western areas by Tuesday night into midweek. While most showers during this period will favor windward and mauka areas, some could reach leeward areas, especially Tuesday night into Wednesday. This pattern of occasional light showers in our typically dry leeward areas may persist into the latter part of the week as the pressure gradient tightens, resulting in brisk easterly trades across the islands. && .AVIATION... Moderate to locally breezy trades will continue at least through midweek. Low cigs and SHRA will favor windward and mauka zones. Brief periods of MVFR conds are possible. A few SHRA may make it to lee sides heading into Monday. AIRMET Sierra is in effect for mtn obsc for windward Big Island. AIRMET Tango is in effect for low level turb lee of terrain due to gusty trade winds. && .MARINE... A high pressure ridge north of the islands will keep moderate to strong trade winds blowing across the Hawaii region. The ridge north of the state will strengthen from Wednesday onward with increasing wind speed trends in the easterly trades. A Small Craft Advisory (SCA) remains in effect for the windier channels and waters around Maui County and the Big Island through Monday. This SCA for these windier waters will likely continue through the week, expanding in coverage from Wednesday onward. Surf along south facing shores has fallen below High Surf Advisory levels this morning. Surf heights will continue to slowly decline as the south swell fades through Monday. Only background small, medium to long period, south to southeast swell energy will move into the region for the rest of the week. North shore surf will see only small medium period northwest pulses providing a tiny increases through the week. Surf along east shores will remain small and choppy each day due to continued trade winds. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Monday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Gibbs AVIATION...Walsh MARINE...Bohlin