West Kaua’i

Tonight: Partly cloudy with isolated showers. Lows 72 to 77 near the shore to around 63 above 3000 feet. East winds up to 10 mph. Chance of rain 20 percent.

Thursday: Mostly sunny with isolated showers. Highs 87 to 93 near the shore to around 78 above 3000 feet. East winds up to 15 mph shifting to the west in the afternoon. Chance of rain 20 percent.

Thursday Night: Partly cloudy with isolated showers. Lows 71 to 76 near the shore to around 63 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

South Kaua’i

Tonight: Partly cloudy with isolated showers in the evening, then mostly cloudy with scattered showers after midnight. Lows around 75. East winds up to 10 mph. Chance of rain 30 percent.

Thursday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 84 to 92. East winds 10 to 15 mph. Chance of rain 30 percent.

Thursday Night: Mostly cloudy with scattered showers. Lows around 75. East winds 10 to 15 mph. Chance of rain 40 percent.

Kaua’i Mountains

Tonight: Mostly cloudy with scattered showers. Lows 65 to 72 in the valleys to around 61 above 4000 feet. Light winds becoming southeast up to 10 mph after midnight. Chance of rain 40 percent.

Thursday: Partly sunny with scattered showers. Highs 78 to 86 in the valleys to around 69 above 4000 feet. East winds up to 10 mph. Chance of rain 40 percent.

Thursday Night: Mostly cloudy with scattered showers. Lows 65 to 72 in the valleys to around 60 above 4000 feet. East winds up to 15 mph. Chance of rain 50 percent.

North Kaua’i

Tonight: Mostly cloudy with scattered showers. Lows 67 to 75. Southeast winds up to 10 mph. Chance of rain 40 percent.

Thursday: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 81 to 89. East winds up to 15 mph. Chance of rain 30 percent.

Thursday Night: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 66 to 75. Southeast winds up to 10 mph. Chance of rain 40 percent.

East Kaua’i

Tonight: Mostly cloudy with scattered showers. Lows 67 to 79. Southwest winds up to 10 mph shifting to the east after midnight. Chance of rain 40 percent.

Thursday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 77 to 89. East winds around 10 mph. Chance of rain 40 percent.

Thursday Night: Mostly cloudy with scattered showers. Lows 66 to 79. East winds around 10 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Locally breezy trades deliver clouds and showers windward and mauka into next week.

Discussion

Diurnally-driven interior showers over Kauai and Oahu will dissipate with the loss of heating this evening. Strong 597dm ridging anchored just west of the International Dateline builds east through the latter half of the week allowing the trade wind belt to rebound northward and strengthen slightly as typical mid- level stability returns. This in turn favors a return to locally breezy trades which will deliver periodic batches of clouds and showers windward and mauka through the forecast period. Prospects for meaningful rainfall remain limited during this time largely owing to a lack of upstream moisture.

Aviation

An area of enhanced moisture over the western half of the state has resulted in lower clouds, showers, and periods of MVFR over mainly Kauai and windward Oahu this afternoon. This prompted the expansion of AIRMET Sierra for mountian obscuration to these areas, with conditions continuing into this evening. Otherwise, expect mainly VFR conditions across the rest of the state tonight and Thursday with moderate to breezy trades keeping clouds and showers over mainly windward and mauka areas.

Marine

The remnants of Post-Tropical Cyclone Kiko continue to track northwest this afternoon as it weakens just north of the coastal waters. As this occurs, moderate to locally fresh east to southeast trade winds have begun filling in from east to west across the island chain today. By Thursday, high pressure will build north of the coastal waters, marking a return of moderate to locally fresh trade winds. By Friday, a Small Craft Advisory may be needed once again for the typically windy waters and channels around Maui County and the Big Island as locally breezy trades return.
Any lingering easterly swell generated from Kiko will fade tonight, with surf along east-facing shores returning to the more typical trade wind-generated energy on Thursday as moderate to fresh trades fill back into the region.
Surf along south facing shores will remain near or just below the September average for the next few days. A reinforcing south- southwest swell peaked today and will slowly decline through Thursday. Another small bump from the south is possible on Friday. Additionally, multiple small pules of northwest to north- northwest swell energy will generate small surf along north facing beaches throughout the rest of this week and into the weekend.

Fire weather

The return of locally breezy trades will lower humidity to typical values during the remainder of the forecast period. Showers remain rather limited and focused windward and mauka.

HFO Watches/Warnings/Advisories

None.