Hilo

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 66 to 73 near the shore to around 60 at 4000 feet. Northeast winds around 10 mph shifting to the northwest after midnight. Chance of rain 70 percent.

Sunday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 86 near the shore to 66 to 71 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Sunday Night: Mostly cloudy with scattered showers. Lows 67 to 73 near the shore to around 60 at 4000 feet. Northeast winds up to 10 mph in the evening becoming light. Chance of rain 50 percent.

Kona

Tonight: Mostly cloudy. Isolated showers in the evening. Lows 68 to 75 near the shore to around 56 near 5000 feet. Light winds. Chance of rain 20 percent.

Sunday: Partly sunny. Isolated showers in the afternoon. Highs 85 to 90 near the shore to 67 to 72 near 5000 feet. Light winds becoming west up to 10 mph in the afternoon. Chance of rain 20 percent.

Sunday Night: Mostly cloudy. Isolated showers in the evening. Lows 67 to 75 near the shore to around 55 near 5000 feet. Light winds. Chance of rain 20 percent.

Waimea

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 66 to 73 near the shore to 60 to 66 near 3000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Sunday: Mostly sunny with isolated showers in the morning, then partly sunny in the afternoon. Highs around 82 near the shore to 70 to 81 near 3000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

Sunday Night: Mostly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows 66 to 74 near the shore to 60 to 67 near 3000 feet. East winds 10 to 15 mph decreasing to up to 15 mph after midnight. Chance of rain 50 percent.

Kohala

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 66 to 73 near the shore to 60 to 66 near 3000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Sunday: Mostly sunny with isolated showers in the morning, then partly sunny in the afternoon. Highs around 82 near the shore to 70 to 81 near 3000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

Sunday Night: Mostly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows 66 to 74 near the shore to 60 to 67 near 3000 feet. East winds 10 to 15 mph decreasing to up to 15 mph after midnight. Chance of rain 50 percent.

South Big Island

Tonight: Partly cloudy. Breezy. Isolated showers in the evening. Lows around 76 near the shore to around 59 near 5000 feet. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Sunday: Mostly sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 88 near the shore to around 68 near 5000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

Sunday Night: Mostly cloudy. Lows around 76 near the shore to around 58 near 5000 feet. East winds 10 to 15 mph shifting to the northeast after midnight.

Puna

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 66 to 73 near the shore to around 60 at 4000 feet. Northeast winds around 10 mph shifting to the northwest after midnight. Chance of rain 70 percent.

Sunday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 86 near the shore to 66 to 71 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Sunday Night: Mostly cloudy with scattered showers. Lows 67 to 73 near the shore to around 60 at 4000 feet. Northeast winds up to 10 mph in the evening becoming light. Chance of rain 50 percent.

Waikoloa

Tonight: Partly cloudy. Lows 69 to 75 near the shore to 55 to 60 above 4000 feet. East winds 10 to 15 mph.

Sunday: Mostly sunny. Highs 85 to 91 near the shore to 67 to 75 above 4000 feet. Northeast winds 10 to 15 mph shifting to the northwest in the afternoon.

Sunday Night: Mostly cloudy. Lows 70 to 76 near the shore to 54 to 59 above 4000 feet. Northeast winds around 10 mph.

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