West Kaua’i

Tonight: Partly cloudy with isolated showers. Lows around 71 near the shore to around 61 above 3000 feet. Northeast winds up to 10 mph. Chance of rain 20 percent.

Thursday: Mostly sunny. Isolated showers in the morning. Highs 84 to 90 near the shore to around 76 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Thursday Night: Mostly clear. Lows around 72 near the shore to around 62 above 3000 feet. East winds up to 10 mph.

South Kaua’i

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows around 72. Northeast winds 10 to 15 mph. Chance of rain 30 percent.

Thursday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 88. East winds 10 to 15 mph. Chance of rain 40 percent.

Thursday Night: Mostly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 73. Northeast winds 10 to 15 mph. Chance of rain 40 percent.

Kaua’i Mountains

Tonight: Mostly cloudy with scattered showers. Lows 63 to 69 in the valleys to around 58 above 4000 feet. East winds up to 15 mph increasing to 10 to 15 mph after midnight. Chance of rain 50 percent.

Thursday: Partly sunny with scattered showers. Highs 75 to 84 in the valleys to around 66 above 4000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Thursday Night: Breezy. Mostly cloudy with scattered showers. Lows 65 to 70 in the valleys to around 59 above 4000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

North Kaua’i

Tonight: Partly cloudy with scattered showers. Lows 65 to 73. East winds up to 15 mph. Chance of rain 40 percent.

Thursday: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 77 to 86. East winds up to 15 mph. Chance of rain 40 percent.

Thursday Night: Partly cloudy with scattered showers. Lows 66 to 74. East winds 10 to 15 mph. Chance of rain 40 percent.

East Kaua’i

Tonight: Mostly cloudy with scattered showers. Lows 63 to 76. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Thursday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 73 to 86. East winds 10 to 15 mph. Chance of rain 50 percent.

Thursday Night: Mostly cloudy with scattered showers. Lows 64 to 76. East winds 10 to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Moderate to breezy trade winds will continue through the week, then strengthen to breezy to locally windy by early next week. Conditions remain mostly dry, with clouds and showers focused over mainly windward and mauka areas during the overnight and early morning hours.

Discussion

Moderate to locally breezy trades have developed across the state this afternoon as high pressure builds far northeast of the area. Mostly dry conditions continue with pockets of clouds and showers moving into windward and mauka areas at times. An incoming batch of moisture will impact windward Big Island and Maui this evening, but rainfall amounts should remain light. Otherwise, expect mostly clear to partly cloudy skies and passing showers under stable conditions.
Trades will strengthen further over the weekend, becoming breezy to locally windy by early next week as high pressure continues to build north of the islands and a drier airmass moves into the area. The combination of drier conditions with stronger trades could bring elevated fire weather concerns. While this is still several days out, and confidence remains low at the moment, conditions will be monitored leading up to the weekend and into next week.

Aviation

High pressure to the north will keep moderate to locally breezy trade winds in place through the next several days with strengthening expected tomorrow through the weekend as the high pressure strengthens. Trade wind showers should follow a diurnal trend of wetter at night and drier during the day, and be mostly confined to windward and mountain areas. A few of these showers could occasionally spill over to leeward areas, and any showers especially in the night time or early morning could have MVFR conditions. Overall VFR conditions are expected.
No AIRMETs are currently in place however windward and mountain areas could receive more MVFR conditions tonight or early tomorrow morning, and there is good a chance of AIRMET Tango tomorrow for low level turbulence as the trade winds strengthen.

Marine

A weak trough to the northwest of the state will continue to maintain gentle to locally fresh easterly trade winds across the state through Thursday as it drifts slowly westward. High pressure far north of the state will strengthen Friday into the weekend with fresh to locally strong trade winds expected. Winds are expected to further strengthen early next week with widespread strong trade winds possible. A Small Craft Advisory (SCA) could return as early as Thursday morning or afternoon for the windier waters and channels around Maui County and the Big Island.
The current south swell will slowly decline over the next couple of days. Surf heights should still hold near the summer time average (5 feet) till around Thursday before dropping Friday into the weekend. Tiny, long-period south swell energy will hold into next week, with below average surf expected.
Along east facing shores, surf will continue to remain smaller than average due to the lack of strong trades. An increase of rough and choppy surf is expected this weekend into next week as the trade winds strengthen. No significant swells are expected through next week.

HFO Watches/Warnings/Advisories

None.