Hilo

Rest Of Tonight: Mostly cloudy with occasional showers. Lows 62 to 71 near the shore to around 56 at 4000 feet. North winds up to 15 mph. Chance of rain 90 percent.

Thursday: Mostly cloudy with showers likely in the morning, then mostly sunny with scattered showers in the afternoon. Highs 77 to 82 near the shore to 62 to 67 at 4000 feet. Northeast winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 70 percent.

Thursday Night: Mostly cloudy. Showers likely in the evening, then scattered showers after midnight. Lows 60 to 70 near the shore to 51 to 56 at 4000 feet. North winds up to 15 mph. Chance of rain 70 percent.

Kona

Rest Of Tonight: Mostly cloudy early in the evening then becoming partly cloudy. Scattered showers early in the evening, then isolated showers after midnight. Lows around 73 near the shore to around 55 near 5000 feet. Light winds. Chance of rain 50 percent.

Thursday: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 83 to 89 near the shore to around 69 near 5000 feet. Light winds. Chance of rain 50 percent.

Thursday Night: Mostly cloudy in the evening then becoming partly cloudy. Isolated showers. Lows 70 to 75 near the shore to 50 to 56 near 5000 feet. Light winds. Chance of rain 20 percent.

Waimea

Rest Of Tonight: Breezy. Mostly cloudy with scattered showers. Lows 63 to 71 near the shore to 57 to 65 near 3000 feet. East winds 10 to 25 mph with gusts to 45 mph. Chance of rain 50 percent.

Thursday: Windy. Mostly sunny with scattered showers. Highs around 79 near the shore to 66 to 77 near 3000 feet. East winds 10 to 30 mph with gusts to 50 mph. Chance of rain 50 percent.

Thursday Night: Breezy. Mostly cloudy with scattered showers. Lows 62 to 70 near the shore to 54 to 63 near 3000 feet. East winds 10 to 25 mph with gusts to 50 mph. Chance of rain 50 percent.

Kohala

Rest Of Tonight: Breezy. Mostly cloudy with scattered showers. Lows 63 to 71 near the shore to 57 to 65 near 3000 feet. East winds 10 to 25 mph with gusts to 45 mph. Chance of rain 50 percent.

Thursday: Windy. Mostly sunny with scattered showers. Highs around 79 near the shore to 66 to 77 near 3000 feet. East winds 10 to 30 mph with gusts to 50 mph. Chance of rain 50 percent.

Thursday Night: Breezy. Mostly cloudy with scattered showers. Lows 62 to 70 near the shore to 54 to 63 near 3000 feet. East winds 10 to 25 mph with gusts to 50 mph. Chance of rain 50 percent.

South Big Island

Rest Of Tonight: Mostly clear. Breezy. Isolated showers early in the evening. Lows around 77 near the shore to around 59 near 5000 feet. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Thursday: Mostly sunny. Windy. Isolated showers in the afternoon. Highs around 86 near the shore to around 68 near 5000 feet. East winds up to 25 mph increasing to 10 to 30 mph in the afternoon. Chance of rain 20 percent.

Thursday Night: Mostly clear. Breezy. Isolated showers in the evening. Lows around 76 near the shore to around 57 near 5000 feet. East winds 10 to 25 mph shifting to the northeast after midnight. Chance of rain 20 percent.

Puna

Rest Of Tonight: Mostly cloudy with occasional showers. Lows 62 to 71 near the shore to around 56 at 4000 feet. North winds up to 15 mph. Chance of rain 90 percent.

Thursday: Mostly cloudy with showers likely in the morning, then mostly sunny with scattered showers in the afternoon. Highs 77 to 82 near the shore to 62 to 67 at 4000 feet. Northeast winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 70 percent.

Thursday Night: Mostly cloudy. Showers likely in the evening, then scattered showers after midnight. Lows 60 to 70 near the shore to 51 to 56 at 4000 feet. North winds up to 15 mph. Chance of rain 70 percent.

Waikoloa

Rest Of Tonight: Mostly clear. Breezy. Isolated showers early in the evening. Lows around 75 near the shore to 53 to 58 above 4000 feet. East winds up to 25 mph with gusts to 45 mph. Chance of rain 20 percent.

Thursday: Sunny and windy. Highs 82 to 89 near the shore to 66 to 72 above 4000 feet. Northeast winds up to 30 mph with gusts to 50 mph.

Thursday Night: Mostly clear. Windy. Isolated showers in the evening. Lows around 73 near the shore to 50 to 56 above 4000 feet. East winds up to 30 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Trade winds will steadily strengthen through Thursday and a wind advisory has been issued for areas of Maui County and Big Island through Thursday night. Passing showers will continue to move in on breezy to windy trade winds through at least early next week. As usual, these showers will be most frequent during the nights and early morning hours across windward and mauka areas.

Update

No major changes with the forecast this evening. Winds are still on track to steadily increase through Thursday. Wind gusts of around 50 mph have already been measured at select sites downwind of terrain over Maui County and the Big Island this evening. Satellite imagery continues to show passing showers riding in with the strong trade winds focused over windward and mauka areas. A few leeward showers will also be possible tonight.

Prev discussion

Issued at 337 PM HST Wed May 20 2026 Satellite shows partly to mostly cloudy skies and scattered showers mainly windward and mauka, with isolated showers over South Kona on Big Island. Winds have increased today, averaging 15 to 25 mph with gusts 30 to 40 mph in a few favored locations.
A drier air mass is moving in tonight, and the inversion will lower and strengthen. This will result in gusty winds over and lee side of terrain. Winds are expected to reach advisory thresholds tonight into Thursday for the windier areas around Maui County and the Big Island, where gusts of up to 50 mph will be possible. For Oahu, wind gusts should be slightly weaker but gusts of at least 40 mph should be expected for areas downwind of terrain by late Thursday. Oahu is not currently in the wind advisory as winds are expected to be below advisory thresholds.
For the weekend, windy conditions will likely continue through Saturday. Trade winds should weaken slightly Sunday, but breezy to occasionally strong trades will likely continue into early next week. Trade wind showers will continue to pass through from time to time and will mainly be focused over windward and mauka areas.

Aviation

Issued at 337 PM HST Wed May 20 2026 Fresh to strong trades will increase tonight and will be locally windy through at least Thursday night as the atmosphere stabilizes. AIRMET Sierra is in effect for mountain obscuration across windward portions of the Big Island, and as a diffuse band of moisture moves through tonight, AIRMET Sierra could be needed over windward slopes elsewhere. AIRMET Tango is in place for low level turbulence over and downwind of terrain. With winds building and stability increasing, this AIRMET will remain in place for at least the next couple of days.

Marine

Issued at 337 PM HST Wed May 20 2026
The high pressure ridge north of the Hawaiian Islands will strengthen over the next few days, allowing trade wind speeds to increase into the strong to gale range tonight through early Friday morning. A Gale Warning has been issued for the Alenuihaha and Pailolo Channels, and Maalaea Bay starting this evening and the Small Craft Advisory (SCA) has been expanded to all remaining island waters. Expect SCA to continue into the first half of next week.
Small, short- to medium-period north-northwest (330 degree) swell energy will decline through Thursday. The next small north- northwest (330 degree) swell will move into the Hawaii region on Saturday, increasing surf heights along north- and west-facing shores through the weekend.
A series of small, long-period south swells will support near- average surf along south-facing shores over the next several days. Meanwhile, strengthening trades will maintain elevated surf along east-facing shores into next week.

HFO Watches/Warnings/Advisories

Wind Advisory until 6 AM HST Friday for Big Island North, Big Island South, Big Island Southeast, Kahoolawe, Kohala, Lanai Leeward, Lanai Mauka, Lanai South, Lanai Windward, Maui Central Valley North, Maui Central Valley South, Maui Leeward West, Maui Windward West, Molokai Leeward South, Molokai North, Molokai Southeast, Molokai West, Molokai Windward, South Haleakala.
Small Craft Advisory until 6 AM HST Friday for 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, Maui County Leeward Waters, Maui County Windward Waters, Oahu Leeward Waters, Oahu Windward Waters.
Gale Warning until 6 AM HST Friday for Alenuihaha Channel, Maalaea Bay, Pailolo Channel.

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Data Courtesy of NOAA.gov