FXHW60 PHFO 200642 AFDHFO Area Forecast Discussion National Weather Service Honolulu HI 842 PM HST Tue May 19 2026 .SYNOPSIS... Trade winds will steadily increase Wednesday through Thursday night and will bring windy conditions by Thursday. Wind speeds could increase to wind advisory level, especially over Maui County and the Big Island on Thursday. Passing showers will continue to ride in with the breezy to windy trade winds through the weekend. && .UPDATE... Latest satellite imagery shows a band of moisture just east of the state which should be arriving late tonight into Wednesday morning. Scattered showers will ride in with the strengthening trade winds, which should mainly be focused over windward and mauka area. A few showers will also be possible over leeward areas. A drier air mass will move in late Wednesday into Thursday, but with the windy conditions, light passing showers are still expected over windward and mauka areas. && .PREV DISCUSSION... Issued at 316 PM HST Tue May 19 2026 Radar showed scattered showers over the Kona slopes this afternoon, along with isolated windward and mauka showers on all islands. Cloud cover ranged from mostly clear to overcast, with the clearer conditions generally over leeward areas. Showers should weaken around sunset, but a few will continue overnight mainly windward and mauka. Models remain consistent showing trade winds drying out and increasing in speed through Thursday. Higher wind speeds, potentially reaching wind advisory level, will arrive tomorrow and continue into Friday and perhaps Friday night. Showers will decrease both in number and intensity once the drier air arrives, with the main drying occurring Wednesday afternoon into the evening. A consistent moderate to occasionally strong trade wind flow is expected to continue through the weekend and well into next week as a large surface high to our north remains strong enough to dominate our weather. A band or two of enhanced moisture may arrive after the weekend, but it's too soon to time that out reliably. && .AVIATION... Moderate to fresh trade winds will strengthen Wednesday and Thursday as high pressure builds. Showers will mostly affect windward and mountain areas as well as the night time and early morning hours. Drier air could fill in later tomorrow night, limiting showers. AIRMET Sierra for mountain obscuration may be needed tomorrow morning, before drier conditions settle in later on Wednesday. The increasing trade winds and inversion tonight and Wednesday will likely require AIRMET Tango. && .MARINE... Issued at 316 PM HST Tue May 19 2026 Locally fresh trades become strong with localized near-gales during the latter half of the week. The Small Craft Advisory (SCA) remains in effect and will eventually be expanded to all waters as winds and seas build later this week. Small, short to medium period NNW swell filling in today. This will be followed later this week by a small NNW swell emanating from a strong low near the Aleutian Islands. A series of small, long period SSW swells supports near-average surf along S shores. Meanwhile, strengthening trades maintain elevated surf and short period fresh swell along E facing shores into next week. && .HFO WATCHES/WARNINGS/ADVISORIES... Small Craft Advisory until 6 PM HST Wednesday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel. && $$ Update...Kino DISCUSSION...Parker AVIATION...Tsamous MARINE...JVC