Area Forecast Discussion
Issued by NWS Honolulu, HI
Issued by NWS Honolulu, HI
148 FXHW60 PHFO 180159 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 359 PM HST Mon Jun 17 2024 .SYNOPSIS... A high pressure ridge north of the state will maintain breezy trade winds through Tuesday with trades strengthening Wednesday onward. Breezy to strong trade winds are expected Wednesday through the weekend. A weak upper low over the state will help produce periods of showers mainly over the windward and mountain areas through Tuesday. Drier conditions are briefly expected Wednesday with scattered showers returning Thursday. Remnants of an old frontal boundary will likely increase shower activity late Friday into Saturday. && .DISCUSSION... A weak upper level low over the state is producing high clouds across portions of the state this afternoon. For tonight through Tuesday, we should be in a fairly similar weather pattern with breezy trade winds and passing showers. Showery activity will be slightly higher than our typical summer day due to the upper level low, with some moderate showers possible over windward areas. As the upper level low gradually moves westward over the next few days, we should see drier conditions with lower inversions on Wednesday. Starting Wednesday into Thursday, the high centered far north of the state will strengthen and will increase the trade wind speeds. Breezy to strong trades are expected during the second half of the week and it may even strengthen a little more this weekend. Overall a windy weekend is expected and it could reach wind advisory threshold for select areas, especially the windier zones around Maui County and the Big Island. On Friday, models are showing moisture associated with an old frontal boundary riding in with the trade winds, which could produce showery weather especially across select windward areas late Friday into Saturday. && .AVIATION... Breezy easterly trades will continue, with clouds and showers favoring windward and mauka locations. Periods of MVFR conditions will impact these windward sections mainly during the overnight to early morning hours. Otherwise, VFR conditions will prevail. AIRMET Tango is in effect for tempo moderate turbulence between 140 and FL300 from the Big Island up through Maui. These conditions will continue into the evening. AIRMET Sierra will likely be needed for windward areas later this evening as shower coverage increases. && .MARINE... A high pressure ridge will remain north of the area and will gradually strengthen during the second half of the week. Moderate to locally strong trade winds are expected through Tuesday as a Small Craft Advisory (SCA) is currently in effect for the typical windier waters around Maui County and the Big Island. Trade winds look to strengthen across all waters as the SCA is likely to be expanded to add the waters around Kauai and Oahu potentially starting Wednesday through the end of the week. The current south swell will continue to slowly fade. For the rest of the week, expect only background small, medium to long period, south to southeast swell energy moving through the local waters. Surf along north facings shores had a slight bump up today and will hold through tonight before slowly declining Tuesday. Weak lows continue to sweep across the northwest Pacific as north facing shores will remain tiny to small with background energy through the week. Surf along east shores will become increasingly rough and choppy from Wednesday onward as the trade winds strengthen across the state. An SCA for seas up to 10 feet is possible for the windier zones around the Big Island during this time too. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Tuesday for Maalaea Bay- Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. && $$ DISCUSSION...Kino AVIATION...Farris MARINE...Shigesato