West Kaua’i

Tonight: Mostly clear. Lows around 73 near the shore to around 63 above 3000 feet. Northeast winds 10 to 15 mph.

Sunday: Mostly sunny. Highs 85 to 92 near the shore to around 77 above 3000 feet. East winds 10 to 15 mph.

Sunday Night: Partly cloudy. Lows around 72 near the shore to around 63 above 3000 feet. Northeast winds around 10 mph.

South Kaua’i

Tonight: Partly cloudy. Breezy. Isolated showers in the evening, then scattered showers after midnight. Lows 71 to 76. Northeast winds 10 to 20 mph. Chance of rain 40 percent.

Sunday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 78 to 90. Northeast winds 10 to 15 mph. Chance of rain 40 percent.

Sunday Night: Partly cloudy with isolated showers. Lows 70 to 76. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Kaua’i Mountains

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 68 in the valleys to around 61 above 4000 feet. Northeast winds 10 to 25 mph. Chance of rain 50 percent.

Sunday: Breezy. Partly sunny with scattered showers. Highs 74 to 81 in the valleys to around 68 above 4000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Sunday Night: Partly cloudy in the evening then becoming mostly cloudy. Breezy. Scattered showers. Lows around 68 in the valleys to around 60 above 4000 feet. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

North Kaua’i

Tonight: Breezy. Partly cloudy with scattered showers. Lows 64 to 75. East winds 10 to 20 mph. Chance of rain 40 percent.

Sunday: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 72 to 86. East winds 10 to 15 mph. Chance of rain 40 percent.

Sunday Night: Partly cloudy with isolated showers. Lows 64 to 74. East winds up to 15 mph. Chance of rain 20 percent.

East Kaua’i

Tonight: Mostly cloudy with scattered showers. Lows 67 to 76. East winds 10 to 15 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 77 to 86. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Sunday Night: Partly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows 67 to 75. Northeast winds 10 to 15 mph. Chance of rain 40 percent.

Detailed Forecast

Synopsis

Locally breezy trade winds will continue but ease a bit early next week. A trend toward fewer windward and mauka showers, and more sunshine, is expected Sunday as drier air pushes in on the trades. At this time, we don't see any significant areas of enhanced moisture moving toward the state, so relatively dry trades should continue through late next week.

Short term update

Latest water vapor imagery depicts the Hawaiian Islands engulfed in a drier air mass, evident by the lack of moisture portrayed on the radar this evening. The most recent One-Hour Rainfall Summary for the state supports this, with most locations receiving no rainfall, where the only exception being right along the Kona slopes of the Big Island with a couple tenths of an inch falling. This trend is expected to continue through at least tomorrow, followed by the more typical windward and mauka trade showers thereafter. The current forecast describes this situation well, therefore, no amendments will be made for this evening's update.

Prev discussion

Issued at 308 PM HST Sat Jul 18 2026 Radar shows only isolated light showers this afternoon as an area of higher moisture has now moved west of the state. Winds were moderate to breezy, with sustained winds averaging 10 to 20 mph and gusts blowing 20 to 30 mph (30-35 at the usual windy spots).
A strong surface high well to the north will keep moderate to occasionally breezy trade winds blowing for the next week (at least), with only slight variations in speed. Showers should be relatively light because moisture will be limited, with PW values coming in around a quarter inch below normal. Models are not displaying any significant areas of increased moisture headed toward the state over the next 5-7 days.
We are keeping an eye on the developing tropical disturbance several hundred miles SW of Ixtapa, Mexico. Various ensemble systems have been showing a small potential for this system to bring us some tropical trouble in about a week and a half or so. It's much too early to forecast any details, and please note that may ensemble members don't bring it near the state. However, let it serve as a good reminder to stay, or become, prepared.

Aviation

Issued at 308 PM HST Sat Jul 18 2026 Moderate trades will continue through Sunday, with just a slight decrease in speed tomorrow. Clouds and isolated to scattered showers will remain over windward and mauka locations. Conditions will be VFR apart from isolated MVFR over windward and mauka areas in clouds and showers.
No AIRMETs are in effect.

Marine

Fresh to locally strong trades will continue through Sunday, and a Small Craft Advisory (SCA) remains in effect for the typically windy areas around Maui and the Big Island through 6 pm Sunday. The trades will ease Sunday night and Monday as high pressure north of the islands weakens, with the trades then holding at moderate speeds through Tuesday. The trades will then restrengthen back to fresh to locally strong speeds Wednesday and Thursday as high pressure strengthens north of the island chain.
Surf along south facing shores will remain near the summertime average tonight. A larger, south swell is expected to build late Sunday and Sunday night, then peak close to advisory levels late Monday through early Wednesday. As this swell slowly fades during the middle of next week, a new long period south swell will arrive on Thursday, keeping surf elevated through next weekend.
Surf along north-facing shores will remain at flat to tiny levels through next weekend.
Surf along east facing shores will remain close to seasonal levels through Monday, then lower slightly Tuesday and Wednesday, before building back close to seasonal levels late next week and through the weekend. Additionally, swell from Tropical Storm Elida may give a slight boost to east shore surf during the middle of next week.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST Sunday for Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters, Maalaea Bay.

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Data Courtesy of NOAA.gov