The moist trades we have been experiencing will give way to drier trade winds beginning tonight. A consistent pattern of mostly moderate but occasionally strong trades should continue well into next week and perhaps beyond. Wind speeds will increase Wednesday through Thursday night, possibly to wind advisory level, then decrease slightly this weekend.
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.
Moderate to locally fresh trade winds will strengthen on Wednesday as the atmosphere gradually becomes more stable. Periods of MVFR conditions will primarily affect windward mountain areas, and AIRMET Sierra for mountain obscuration may be needed tonight and tomorrow morning, with drier conditions settling over the islands Wednesday afternoon. Conditions are borderline for moderate low level turbulence this afternoon, but the set up will become increasingly conducive tonight and Wednesday, which will require AIRMET Tango.
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.
Small Craft Advisory until 6 PM HST Wednesday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.
