Hilo

Tonight: Mostly cloudy with scattered showers. Lows 67 to 74 near the shore to around 60 at 4000 feet. Light winds. Chance of rain 50 percent.

Wednesday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 79 to 88 near the shore to 67 to 74 at 4000 feet. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 50 percent.

Wednesday Night: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows 68 to 75 near the shore to around 62 at 4000 feet. North winds up to 10 mph. Chance of rain 50 percent.

Kona

Tonight: Partly cloudy. Isolated showers in the evening. Lows 69 to 76 near the shore to around 57 near 5000 feet. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs around 87 near the shore to around 70 near 5000 feet. Light winds. Chance of rain 30 percent.

Wednesday Night: Partly cloudy. Scattered showers in the evening. Lows 70 to 77 near the shore to around 57 near 5000 feet. Light winds. Chance of rain 40 percent.

Waimea

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 67 to 74 near the shore to 61 to 68 near 3000 feet. Light winds. Chance of rain 40 percent.

Wednesday: Mostly sunny in the morning then becoming partly sunny. Scattered showers. Highs 66 to 85. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 40 percent.

Wednesday Night: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows 68 to 75 near the shore to 63 to 69 near 3000 feet. East winds around 10 mph. Chance of rain 50 percent.

Kohala

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 67 to 74 near the shore to 61 to 68 near 3000 feet. Light winds. Chance of rain 40 percent.

Wednesday: Mostly sunny in the morning then becoming partly sunny. Scattered showers. Highs 66 to 85. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 40 percent.

Wednesday Night: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows 68 to 75 near the shore to 63 to 69 near 3000 feet. East winds around 10 mph. Chance of rain 50 percent.

South Big Island

Tonight: Partly cloudy. Isolated showers in the evening. Lows around 76 near the shore to around 61 near 5000 feet. Northeast winds up to 10 mph in the evening becoming light. Chance of rain 20 percent.

Wednesday: Sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs around 86 near the shore to around 71 near 5000 feet. Light winds. Chance of rain 30 percent.

Wednesday Night: Partly cloudy. Isolated showers in the evening. Lows around 77 near the shore to around 62 near 5000 feet. Light winds. Chance of rain 20 percent.

Puna

Tonight: Mostly cloudy with scattered showers. Lows 67 to 74 near the shore to around 60 at 4000 feet. Light winds. Chance of rain 50 percent.

Wednesday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 79 to 88 near the shore to 67 to 74 at 4000 feet. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 50 percent.

Wednesday Night: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows 68 to 75 near the shore to around 62 at 4000 feet. North winds up to 10 mph. Chance of rain 50 percent.

Waikoloa

Tonight: Partly cloudy with isolated showers. Lows 71 to 76 near the shore to 56 to 61 above 4000 feet. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny. Isolated showers in the afternoon. Highs 84 to 90 near the shore to around 72 above 4000 feet. Light winds. Chance of rain 20 percent.

Wednesday Night: Mostly clear. Isolated showers in the evening. Lows 72 to 77 near the shore to around 59 above 4000 feet. Light winds. Chance of rain 20 percent.

Detailed Forecast

Synopsis

A more seasonal trade wind pattern has returned to the state with the exit of Hurricane Lala. Expect typical trade wind showers focused along windward and mauka areas through tonight. Trade winds weaken Wednesday into the latter half of the week as a trough passes northeast of the islands. The trough also brings an increase in moisture that will produce an uptick in shower activity through Friday. This weekend, trade winds restrengthen.

Short term update

Forecast looks on track for tonight and Wednesday, so no updates are anticipated this evening.

Prev discussion

Issued at 344 PM HST Tue Aug 18 2026
The return of the trade winds will bring areas of showers over windward and mauka locations through tonight. Trades weaken Wednesday through Friday as a trough passes northeast of the islands. Lighter trades will increase precipitation chances for leeward areas with the development of a sea/land breeze pattern.
The winds are expected to strengthen and shift easterly late Friday into Saturday, which will pull additional moisture into the area. This will increase precipitation chances for early in the weekend. Highest chances will be on the windward and mauka parts of the islands.
For Sunday and Monday, tropical moisture is expected to be in the vicinity of the state due to the potential development of a tropical system. Most guidance keeps the track of the potential tropical system south of the islands. While there remains uncertainty in the forecast since the system has yet to develop, precipitation chances have been increased for early next week. Please continue to monitor the forecast as it is subject to change as we get closer to the weekend and details surrounding the forecast become clearer.

Aviation

Moderate trades expected through tomorrow. Some windward and mauka SHRA possible with isol MVFR conds. VFR conditions should prevail.
No AIRMETs are currently in effect.

Marine

High pressure far northeast of the waters will remain nearly stationary and slowly weaken for the next couple of days. Trade winds will continue a weakening trend, becoming light and variable for most waters by Thursday as daytime sea breezes and overnight land breezes become established. By late Friday, moderate to locally fresh trades will begin to build back into the region as the high drifts southward closer to the island chain. Heading into the weekend, the potential development of a tropical system southeast of the islands is possible but uncertainty remains as the system has yet to develop.
Surf along south facing shores will continue declining through midweek as south swell fades. Another long period south swell generated from gales just south and east of New Zealand will begin arriving late this week. Surf along east facing shores will also continue to fade as background flow becomes weaker. North facing shores will remain tiny throughout the week.

Fire weather

Issued at 340 PM HST Tue Aug 18 2026
Moderate trade winds will prevail through tonight. Trade winds will weaken Wednesday through Friday, increasing chances of showers for the leeward side of the islands. Trade winds increase over the weekend into early next week with increased chances of precipitation. The inversion is 6000 to 7000 ft.

HFO Watches/Warnings/Advisories

None.

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Data Courtesy of NOAA.gov