West Kaua’i

Tonight: Partly cloudy with isolated showers. Lows around 74 near the shore to around 64 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Friday: Mostly sunny. Isolated showers in the morning. Highs 85 to 91 near the shore to around 76 above 3000 feet. Northeast winds up to 15 mph. Chance of rain 20 percent.

Friday Night: Partly cloudy. Isolated showers after midnight. Lows around 74 near the shore to around 64 above 3000 feet. East winds 10 to 15 mph shifting to the northeast after midnight. Chance of rain 20 percent.

South Kaua’i

Tonight: Locally breezy. Mostly cloudy with scattered showers. Lows 72 to 78. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Friday: Partly sunny. Locally breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 79 to 89. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Friday Night: Locally breezy. Mostly cloudy with scattered showers. Lows 71 to 78. Northeast winds 15 to 20 mph. Chance of rain 50 percent.

Kaua’i Mountains

Tonight: Locally breezy. Mostly cloudy with scattered showers. Lows around 69 in the valleys to around 61 above 4000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Friday: Mostly cloudy with scattered showers. Highs 73 to 80 in the valleys to around 66 above 4000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Friday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 66 to 71 in the valleys to around 61 above 4000 feet. East winds around 15 mph. Chance of rain 70 percent.

North Kaua’i

Tonight: Mostly cloudy with scattered showers. Lows 64 to 75. East winds up to 15 mph. Chance of rain 50 percent.

Friday: Partly sunny with scattered showers. Highs 70 to 86. East winds up to 15 mph. Chance of rain 50 percent.

Friday Night: Mostly cloudy with scattered showers. Lows 64 to 75. East winds 10 to 15 mph. Chance of rain 50 percent.

East Kaua’i

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 68 to 78. Northeast winds 10 to 15 mph. Chance of rain 70 percent.

Friday: Mostly cloudy with scattered showers. Highs 76 to 85. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Friday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 68 to 78. Northeast winds 10 to 15 mph. Chance of rain 70 percent.

Detailed Forecast

Synopsis

Strong high pressure far north of the state will continue to produce breezy trades into the weekend. One batch of trade wind showers will spread across mainly Maui and the Big Island tonight with a quick downpour or two possible windward. Another increase in moisture will bring enhanced showers to mostly windward and mauka locations Saturday night into Sunday. Otherwise fairly typical trade wind weather is expected.

Short term update

There have been some decent 3 hr rainfall amounts over an inch over portions of windward Big Island. Overall the forecast is on track tonight so no updates are expected.

Prev discussion

Issued at 331 PM HST Thu Jul 9 2026 Very large surface high 1035 mb or so meanders over the far NE Pac the next 10 days, keeping trades breezy with slight slackening expected by the middle of next week. One batch of enhanced showers is rolling into Maui and the BI, associated with higher PW around 1.75″ moving in…enough for a couple of quick windward and mauka downpours. Oahu should be on N fringes of this moisture convergence later tonight and Fri AM. Still another shower area progged near the islands in the ensemble means Sat night into Sun AM. Ridging persists aloft, so nothing too unusual expected with either of these. Otherwise, typical windward and mauka showers expected with PW trending near normal thru midweek next week.
However…the latest ensemble runs and current MJO phase suggest we keep an close eye on the tropics to our S and SE the over the next couple of weeks. There is more agreement in the long range than I'd like to see, that the ITCZ to the S and SE of the islands will become even more active. The subtropical jet shifts N of the islands in a week or so, anticyclonic flow builds aloft SE of the islands, and deeper tropical moisture and much- below- normal surface pressure gradually get established to our S and shift northward. Just a little tap on the shoulder to remind us that while it is quiet over the islands for the time being, we are getting farther into Hurricane Season with what is expected to be a very strong El Nino continuing to build.

Aviation

Moderate to breezy trades will persist across the Hawaiian Islands, bringing in pockets of enhanced low-level showers across predominately windward and mauka areas, occasionally spilling over into leeward areas. Expect VFR conditions to prevail across most locations, with occasional localized MVFR/IFR conditions in association with shower activity.
AIRMET Sierra is in effect for mountain obscuration above 2500 feet for windward Kauai, Oahu, Maui, and the Big Island. This is expected to persist throughout the period as shower activity continues, even if showers prove to be intermittent at times.
AIRMET Tango remains in effect for moderate low-level turbulence over and downwind of terrain for all islands. This AIRMET will likely continue through the next several days.

Marine

Issued at 331 PM HST Thu Jul 9 2026 Strong high pressure centered north of the state will remain nearly stationary over the forecast period driving fresh to strong trade winds across the entire coastal waters. The Small Craft Advisory (SCA) is in effect through Friday afternoon for all Hawaiian waters. Trades will remain fresh to strong through the weekend so the SCA may need to be extended but a few leeward zones might drop off.
The current small medium-period south-southwest (190-200 degrees) swell will gradually decline through Friday. A small to moderate, long- period southwest swell (220 degrees) is expected to fill in Saturday into early next week, but due to its Tasman source, could be more inconsistent than the current swell.
Surf along east-facing shores will remain rough and choppy through the forecast period as fresh to strong trades hold. A series of small, moderate- to long-period west (270 to 280 degrees) swells are expected to arrive late Friday and hold into early next week, sourced from Typhoon Bavi in the far western Pacific. Surf along north-facing shores is expected to remain flat to tiny with no significant swells forecast from the north or northwest.
Looking ahead, higher than normal high tides will be possible beginning during the latter half of this weekend. Interests immediately along the coasts in low-lying or vulnerable areas should continue to monitor forecasts for possible coastal flooding due to the King Tides from Sunday through the first half of next week.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST Friday for Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters, Big Island Windward Waters, Kaiwi Channel, Kauai Channel, Kauai Leeward Waters, Kauai Northwest Waters, Kauai Windward Waters, Maalaea Bay, Maui County Leeward Waters, Maui County Windward Waters, Oahu Leeward Waters, Oahu Windward Waters, Pailolo Channel.

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Data Courtesy of NOAA.gov