Hilo

Today: Mostly cloudy. Showers likely in the morning, then scattered showers in the afternoon. Highs around 80 near the shore to 64 to 69 at 4000 feet. East winds up to 15 mph. Chance of rain 60 percent.

Tonight: Mostly cloudy. Showers likely in the evening, then occasional showers after midnight. Lows 65 to 70 near the shore to around 52 at 4000 feet. West winds up to 10 mph. Chance of rain 80 percent.

Friday: Mostly cloudy. Occasional showers in the morning, then scattered showers in the afternoon. Highs around 80 near the shore to 64 to 69 at 4000 feet. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 80 percent.

Kona

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 79 to 84 near the shore to around 64 near 5000 feet. Northwest winds up to 10 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with isolated showers. Lows 68 to 73 near the shore to around 53 near 5000 feet. Light winds. Chance of rain 20 percent.

Friday: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 79 to 84 near the shore to around 64 near 5000 feet. West winds up to 10 mph. Chance of rain 40 percent.

Waimea

Today: Breezy. Partly sunny with scattered showers. Highs around 79 near the shore to 64 to 74 near 3000 feet. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 67 near the shore to 53 to 60 near 3000 feet. East winds up to 20 mph. Chance of rain 50 percent.

Friday: Breezy. Mostly cloudy with scattered showers. Highs around 79 near the shore to 64 to 74 near 3000 feet. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 50 percent.

Kohala

Today: Breezy. Partly sunny with scattered showers. Highs around 79 near the shore to 64 to 74 near 3000 feet. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 67 near the shore to 53 to 60 near 3000 feet. East winds up to 20 mph. Chance of rain 50 percent.

Friday: Breezy. Mostly cloudy with scattered showers. Highs around 79 near the shore to 64 to 74 near 3000 feet. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 50 percent.

South Big Island

Today: Partly sunny. Breezy. Isolated showers in the afternoon. Highs around 82 near the shore to around 68 near 5000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Breezy. Isolated showers in the evening. Lows around 68 near the shore to around 52 near 5000 feet. Northeast winds up to 20 mph. Chance of rain 20 percent.

Friday: Mostly cloudy. Breezy. Isolated showers in the afternoon. Highs around 82 near the shore to around 68 near 5000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Puna

Today: Mostly cloudy. Showers likely in the morning, then scattered showers in the afternoon. Highs around 80 near the shore to 64 to 69 at 4000 feet. East winds up to 15 mph. Chance of rain 60 percent.

Tonight: Mostly cloudy. Showers likely in the evening, then occasional showers after midnight. Lows 65 to 70 near the shore to around 52 at 4000 feet. West winds up to 10 mph. Chance of rain 80 percent.

Friday: Mostly cloudy. Occasional showers in the morning, then scattered showers in the afternoon. Highs around 80 near the shore to 64 to 69 at 4000 feet. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 80 percent.

Waikoloa

Today: Partly sunny. Breezy. Highs around 83 near the shore to 65 to 71 above 4000 feet. East winds up to 15 mph shifting to the north in the afternoon.

Tonight: Mostly cloudy. Breezy. Isolated showers in the evening. Lows 68 to 73 near the shore to 49 to 56 above 4000 feet. Southeast winds up to 20 mph decreasing to up to 10 mph after midnight. Chance of rain 20 percent.

Friday: Mostly cloudy. Highs around 83 near the shore to 65 to 71 above 4000 feet. North winds up to 15 mph.

Detailed Forecast

Synopsis

Moderate to breezy easterly trade winds will continue into the weekend, with showers favoring windward and mauka locations overnight through the morning periods. Upper clouds moving through from the west will lead to periods with cloudy conditions over the next several days. A transition to a wet pattern with strong trades is possible later in the weekend through early next week as an upper disturbance settles southward into the area and strong high pressure builds to the north.

Discussion

Guidance remains in good agreement and depicts a weakness in the ridge that has formed lingering into tonight as a front passes far to the north. Easterly trades over the region have responded and slightly eased into the moderate to breezy category (lightest over the western end of the state). Windward showers will remain light, with very little making it over to our dry leeward areas where drought conditions continue. Guidance does show an area of enhanced low-level moisture upstream moving through the islands tonight into Friday. This moisture combined with upper troughing over the area may lead to better windward shower coverage through this time. In addition to the typical trade wind pattern, expect periods with cloudy conditions to continue due to mid- to upper- level moisture being drawn into the area from the upper trough.
A transition period is possible late in the weekend through early next week as a weak upper low settles southward into the area. Added instability associated with this upper feature combined with increasing moisture and strong trades will translate to a potential wet pattern setting up. Although the bulk of the showers will focus over the typical windward and mauka locations, an eroded inversion plus the strong trades will lead to some showers making it to leeward spots if this scenario evolves. Forecast confidence in the details, however, still remains low due to some model differences shown (GFS being the drier/more stable solution).

Aviation

High pressure northeast of the state will generate moderate trades for all islands through the remainder of today. Thus, scattered showers will be mainly limited to windward locations. Expect bring brief periods of MVFR ceilings and visibility to accompany this activity.
No AIRMETS are currently in effect.

Marine

A trough several hundred miles northwest of the state will keep trades generally in the moderate range today. As the trough weakens and retrogrades westward tonight and Friday, high pressure northeast of the islands will become more dominant, allowing the trade winds to strengthen back to moderate to locally strong levels. The trades will continue to strengthen over the weekend, with strong to near Gale force winds expected Sunday through the middle of next week.
A series of small northwest swells will move through the islands today through Sunday, keeping small surf in place along north facing shores. Surf will trend up early next week as a new moderate sized long-period northwest swell arrives, with surf potentially flirting with advisory levels Tuesday and Wednesday.
Mainly background south swells will roll through the islands over the next few days, keeping small surf in place along south facing shores. A new long-period south swell will arrive Sunday and build to well above the summertime average Monday through the middle of next week.
East shore surf will remain small through Friday, trend up to near seasonal levels over the weekend, then increase to above normal levels Monday through the middle of next week as the trade winds strengthen over and upstream of the island chain.

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