Hilo

Rest Of Tonight: Cloudy with scattered showers. Haze. Lows 61 to 71 near the shore to 52 to 58 at 4000 feet. South winds up to 10 mph. Chance of rain 50 percent.

Tuesday: Mostly cloudy. Scattered showers in the morning, then isolated showers in the afternoon. Haze through the day. Highs around 82 near the shore to 65 to 70 at 4000 feet. South winds up to 15 mph. Chance of rain 40 percent.

Tuesday Night: Mostly clear. Isolated showers in the evening. Haze through the night. Lows 61 to 69 near the shore to 50 to 57 at 4000 feet. Southwest winds up to 10 mph. Chance of rain 20 percent.

Kona

Rest Of Tonight: Cloudy. Haze after midnight. Lows 69 to 75 near the shore to 49 to 54 near 5000 feet. Light winds.

Tuesday: Cloudy in the morning, then mostly sunny with isolated showers in the afternoon. Haze through the day. Highs 83 to 88 near the shore to around 67 near 5000 feet. Light winds. Chance of rain 20 percent.

Tuesday Night: Mostly clear. Haze through the night. Lows around 71 near the shore to 47 to 52 near 5000 feet. Light winds becoming east up to 10 mph after midnight.

Waimea

Rest Of Tonight: Cloudy and haze. Lows 62 to 70 near the shore to 55 to 62 near 3000 feet. Light winds.

Tuesday: Cloudy in the morning then becoming mostly sunny. Haze. Highs around 80 near the shore to 70 to 78 near 3000 feet. Light winds.

Tuesday Night: Mostly clear. Haze. Lows 61 to 70 near the shore to 53 to 61 near 3000 feet. Light winds.

Kohala

Rest Of Tonight: Cloudy and haze. Lows 62 to 70 near the shore to 55 to 62 near 3000 feet. Light winds.

Tuesday: Cloudy in the morning then becoming mostly sunny. Haze. Highs around 80 near the shore to 70 to 78 near 3000 feet. Light winds.

Tuesday Night: Mostly clear. Haze. Lows 61 to 70 near the shore to 53 to 61 near 3000 feet. Light winds.

South Big Island

Rest Of Tonight: Cloudy with isolated showers. Haze through the night. Lows around 74 near the shore to around 55 near 5000 feet. East winds up to 15 mph shifting to the northeast after midnight. Chance of rain 20 percent.

Tuesday: Breezy. Cloudy with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Haze through the day. Highs around 84 near the shore to around 66 near 5000 feet. East winds 10 to 20 mph. Chance of rain 30 percent.

Tuesday Night: Mostly clear. Haze in the evening. Lows around 73 near the shore to around 53 near 5000 feet. East winds 10 to 15 mph.

Puna

Rest Of Tonight: Cloudy with scattered showers. Haze. Lows 61 to 71 near the shore to 52 to 58 at 4000 feet. South winds up to 10 mph. Chance of rain 50 percent.

Tuesday: Mostly cloudy. Scattered showers in the morning, then isolated showers in the afternoon. Haze through the day. Highs around 82 near the shore to 65 to 70 at 4000 feet. South winds up to 15 mph. Chance of rain 40 percent.

Tuesday Night: Mostly clear. Isolated showers in the evening. Haze through the night. Lows 61 to 69 near the shore to 50 to 57 at 4000 feet. Southwest winds up to 10 mph. Chance of rain 20 percent.

Waikoloa

Rest Of Tonight: Cloudy. Haze after midnight. Lows 70 to 75 near the shore to 51 to 56 above 4000 feet. Light winds.

Tuesday: Cloudy in the morning then becoming partly sunny. Haze. Highs around 84 near the shore to 65 to 71 above 4000 feet. Light winds becoming northwest up to 10 mph in the afternoon.

Tuesday Night: Mostly clear. Haze. Lows 69 to 74 near the shore to 49 to 54 above 4000 feet. Light winds.

Detailed Forecast

Update

An update to clarify that the Flood Watch has been cancelled for Oahu but the Flood Watch will remain in effect for Niihau and Kauai through 6 AM HST tomorrow (Tuesday) morning.

Synopsis

A surface trough is oriented NE-SW across Kauai County this afternoon, with thunderstorms forming and moving toward Niihau and Kauai as of 2 PM HST. This trough will move west tonight and remain to the west Tuesday. A new cold front will approach from the northwest Tue night into Wed, adding its moisture and convergence to the remains of the initial trough and moving back southeast toward Kauai County. The main area of concern for potential heavy rain for mid to late-week is therefore Kauai and Niihau. There is a chance that this feature could get near Oahu. After trending away from Oahu the past couple of days, the very latest guidance is moving back toward a higher chance of it reaching the island.

Prev discussion

/ISSUED 306 PM HST Mon Dec 15 2025/
Showers and thunderstorms were located in the Kauai Channel and over and near Kauai and Niihau this afternoon. These were moving northeast, and have a good chance to impact the island through the remainder of the afternoon and possibly in the early evening. Satellite images show lots of high clouds streaming northeast across the entire state, and this is expected to continue into tonight.
Models still show the surface trough near Kauai/Niihau this afternoon (the remains of an old cold front) moving north and west away from the state tonight and remaining there Tuesday. A new cold front will move in from the northwest Tuesday night, pushing an enhanced area of moisture and convergence toward Kauai County. Yesterday this time, models were trending weaker with this system, showing it not making it much farther east than Kauai. However, the latest models now indicate that it could make it to Oahu, or at least close enough to increase rain chances there. Moderate to heavy rain in Kauai County is likely Wed-Thu, and is now looking more possible over/near Oahu during the same time frame.
The area of moisture resulting from this next front appears to get hung up along an east-west axis near or just north of the state by Saturday. A surface high pressure system to our northeast is then forecast to send a round northeast to east trades into the state this coming weekend, and this will keep the area of moisture lingering over the state right into early next week. There is lots of uncertainty concerning how much rain there will be this weekend, but there appears to be a relatively high chance of clouds and a moderate chance at continued showery conditions.

HFO Watches/Warnings/Advisories

Flood Watch until 6 AM HST Tuesday for Niihau, Kauai,
High Surf Advisory until 6 AM HST Tuesday for Niihau, Oahu North Shore, Maui Windward West, Kona, Kohala, Kauai North, Molokai Windward, Molokai North, Maui Central Valley North, Windward Haleakala, Big Island East, Big Island North.
Small Craft Advisory until 6 AM HST Tuesday for Kaiwi Channel, Maui County Windward Waters, Alenuihaha Channel, Big Island Windward Waters.

Big Island Now Weather is brought to you by Blue Hawaiian Helicopters.

Check out their Big Island Helicopter Tours today!

Data Courtesy of NOAA.gov