Hilo

Rest Of Today: Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs 77 to 82 near the shore to 64 to 69 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 59 to 66 near the shore to around 53 at 4000 feet. Light winds.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs 76 to 81 near the shore to 64 to 69 at 4000 feet. Southeast winds up to 15 mph. Chance of rain 40 percent.

Kona

Rest Of Today: Mostly sunny in the morning then becoming partly sunny. Highs 79 to 85 near the shore to around 67 near 5000 feet. Southwest winds up to 10 mph.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Lows around 68 near the shore to 43 to 50 near 5000 feet. Light winds.

Wednesday: Mostly sunny. Isolated showers in the afternoon. Highs 79 to 84 near the shore to around 66 near 5000 feet. Southwest winds up to 10 mph. Chance of rain 20 percent.

Waimea

Rest Of Today: Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 78 near the shore to 67 to 72 near 3000 feet. North winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 59 to 67 near the shore to 50 to 57 near 3000 feet. Light winds.

Wednesday: Mostly sunny. Isolated showers in the afternoon. Highs around 77 near the shore to 66 to 71 near 3000 feet. West winds up to 10 mph. Chance of rain 20 percent.

Kohala

Rest Of Today: Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 78 near the shore to 67 to 72 near 3000 feet. North winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 59 to 67 near the shore to 50 to 57 near 3000 feet. Light winds.

Wednesday: Mostly sunny. Isolated showers in the afternoon. Highs around 77 near the shore to 66 to 71 near 3000 feet. West winds up to 10 mph. Chance of rain 20 percent.

South Big Island

Rest Of Today: Mostly sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 80 near the shore to around 67 near 5000 feet. South winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Lows around 69 near the shore to around 48 near 5000 feet. Light winds.

Wednesday: Sunny. Highs around 80 near the shore to around 66 near 5000 feet. Southwest winds up to 10 mph.

Puna

Rest Of Today: Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs 77 to 82 near the shore to 64 to 69 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 59 to 66 near the shore to around 53 at 4000 feet. Light winds.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs 76 to 81 near the shore to 64 to 69 at 4000 feet. Southeast winds up to 15 mph. Chance of rain 40 percent.

Waikoloa

Rest Of Today: Sunny in the morning then becoming partly sunny. Highs 79 to 84 near the shore to 64 to 69 above 4000 feet. Northwest winds up to 10 mph.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Lows around 69 near the shore to 46 to 52 above 4000 feet. Light winds.

Wednesday: Mostly sunny. Highs 78 to 83 near the shore to 63 to 69 above 4000 feet. West winds up to 15 mph.

Detailed Forecast

Synopsis

Weak troughing over the western islands will keep light winds in the forecast across with land and sea breezes over each island into Wednesday morning. Wind convergence shower bands will also pass into the western islands with a brief increase in shower trends for Kauai and Oahu. A cold front will sweep down the island chain from Wednesday night through Friday, dragging a band of clouds and showers with it. Cool, moderate to breezy north to northeast winds will fill in behind this front from Thursday into the weekend. Moderate to breezy trade wind weather continues through the first half of next week.

Discussion

Using a combination of satellite and local radar imagery we see brief shower bands moving through the western islands this morning with more stable conditions over Maui and the Big Island. The upper air soundings from 2 AM this morning support this analysis with subsidence inversion heights around 7,000 feet above mean sea level (MSL) at Lihue and around 5,500 feet above MSL at Hilo. These showers are associated with two wind convergence bands from the remnants of a dissipated cold front. Scattered showers are forecast over the western islands of Niihau, Kauai, Oahu and Molokai. More isolated shower coverage is likely over Lanai, Maui and the Big Island today.
Strong winds at the Big Island summit level have fallen below warning and advisory thresholds, therefore the High Wind Warning for the summits of Mauna Kea and Mauna Loa was cancelled this morning.
Weak troughing north of Hawaii will keep the subtropical ridge in a weakened state for one more day today. Light large scale winds will allow local scale land and sea breezes to continue to develop over all islands. Day time sea breezes will build clouds and a few showers over island mountain and interior sections in the afternoon to early evening hours. Bands of showers over the western islands will increase morning cloud and shower trends mainly over Kauai and Oahu.
Farther to the northwest a larger cloud band shown on satellite imagery is associated with the next cold front forecast to sweep into the western islands starting Wednesday night. This system will drag clouds and showers across each island as it passes quickly from west to east down the island chain. Expect a 12 hour period of wet weather for each island, followed by cool moderate to breezy northerly winds after frontal passage.
High pressure will rapidly build in behind the front, producing cooler temperatures along with moderate to breezy north to northeast winds from Thursday into the weekend. Model guidance remains in good agreement with this high confidence solution. Moderate to breezy trade winds with passing windward and mountain showers will continue through early next week as a fairly strong high pressure system passes by just north of the Hawaiian Islands this weekend.

Aviation

A weak flow regime persists again today. Some lower level moisture associated with a weak convergence boundary will bring increased cloud cover and isolated showers to Oahu and Kauai. Elsewhere, expect mainly dry weather and VFR conditions. Sea breeze development along the coastal regions early this afternoon may help generate isolated showers over the islands interiors.
No AIRMETs are in effect and none are expected during the forecast period.

Marine

Light and variable winds will hold today, shift out of the southwest tonight, then increase to moderate to fresh speeds through the day Wednesday as a front approaches. Guidance remains persistent and shows this front moving through Wednesday night through Thursday, with a ridge nosing eastward in its wake Thursday through Friday. The surface winds will quickly shift from southwest to northerly as the front moves through Wednesday night. These northerly winds may reach the moderate to fresh range Thursday through Friday as they gradually veer out of the northeast and increase into the fresh to strong category this weekend.
Surf along north and west facing shores will remain small through midweek, with mainly background, short-period northwest energy moving through. A significant northwest (320 degrees) swell associated with a storm-force low located around 2000 NM northwest of the state will arrive late Wednesday night, then rapidly build down the island chain through the day Thursday. This swell will peak late Thursday, then slowly ease Friday into Saturday. A more compact gale passing the state well to the north Friday through Saturday will send a large, medium-period north swell through the area Saturday night through Sunday. Expect surf heights to exceed warning levels Thursday through Friday as the northwest swell moves through, then remain above the advisory levels for exposed north facing shores over the weekend as the north swell arrives.
Coastal impacts associated with a swell of this magnitude Thursday into Friday could be significant due to a combination of moderate to fresh northerly (onshore) winds and the peak daily high tide potentially coinciding with the peak surf anticipated Thursday evening for some areas.
Surf along east facing shores will begin to trend up over the weekend as strong trades return.

HFO Watches/Warnings/Advisories

None.

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