West Side

Tonight: Partly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Lows 65 to 71. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Wednesday: Mostly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 74 to 80. Northeast winds 10 to 25 mph. Chance of rain 40 percent.

Wednesday Night: Breezy. Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows 65 to 72. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

South Side

Tonight: Mostly clear. Breezy. Lows 63 to 73. North winds 10 to 20 mph.

Wednesday: Sunny and breezy. Highs around 83. Northeast winds 10 to 20 mph.

Wednesday Night: Breezy. Mostly cloudy with scattered showers in the evening, then partly cloudy after midnight. Lows 63 to 74. Northeast winds 10 to 20 mph. Chance of rain 40 percent.

North Shore

Tonight: Mostly cloudy with numerous showers. Lows around 67 near the shore to around 49 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 70 percent.

Wednesday: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 80 near the shore to around 63 near 5000 feet. East winds up to 20 mph. Chance of rain 70 percent.

Wednesday Night: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows around 68 near the shore to around 49 near 5000 feet. Southeast winds up to 15 mph increasing to 10 to 15 mph after midnight. Chance of rain 70 percent.

Central Maui

Tonight: Partly cloudy with isolated showers. Lows 63 to 68. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Wednesday: Breezy. Mostly sunny with isolated showers. Highs 77 to 83. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Wednesday Night: Breezy. Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows around 66. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Upcountry

Tonight: Partly cloudy with scattered showers. Lows around 43 at the visitor center to around 40 at the summit. Northeast winds up to 10 mph. Chance of rain 50 percent.

Wednesday: Mostly sunny with scattered showers. Highs around 58 at the visitor center to around 61 at the summit. East winds up to 10 mph. Chance of rain 50 percent.

Wednesday Night: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows around 44 at the visitor center to around 40 at the summit. East winds up to 15 mph. Chance of rain 50 percent.

East Maui

Tonight: Mostly cloudy with numerous showers. Lows around 67 near the shore to around 49 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 70 percent.

Wednesday: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 80 near the shore to around 63 near 5000 feet. East winds up to 20 mph. Chance of rain 70 percent.

Wednesday Night: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows around 68 near the shore to around 49 near 5000 feet. Southeast winds up to 15 mph increasing to 10 to 15 mph after midnight. Chance of rain 70 percent.

Lanai City

Tonight: Mostly clear. Breezy. Lows around 63. Northeast winds 15 to 25 mph.

Wednesday: Breezy. Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs 70 to 78. Northeast winds 20 to 25 mph. Chance of rain 20 percent.

Wednesday Night: Breezy. Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Lows around 63. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Kaunakakai

Tonight: Breezy. Partly cloudy with isolated showers. Lows 54 to 70. Northeast winds 15 to 20 mph. Chance of rain 20 percent.

Wednesday: Breezy. Mostly sunny with isolated showers. Highs 67 to 83. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Wednesday Night: Breezy. Mostly cloudy with scattered showers. Lows 54 to 70. Northeast winds 15 to 20 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Breezy trade winds will continue through the weekend, with clouds and showers favoring windward and mauka areas, especially during overnight and early morning hours. Moisture from a remnant front and an evolving upper-level trough will maintain periods of enhanced shower activity for portions of the state through Thursday. Expect a more typical trade wind pattern to return Friday through the weekend.

Discussion

A remnant frontal boundary remains draped across the Big Island this evening, which has led to a wet pattern today, particularly across windward sections of the Big Island. Observations reflect this at the rain gauges, showing 1 to 3 inches of rainfall over the past 12 hours in this area. This lingering moisture boundary combined with an elevated inversion will support the potential for showery conditions persisting into Wednesday over and around the Big Island. Elsewhere across the state, expect the dry and stable conditions to continue.
Wednesday through the end of the week, guidance shows the surface ridge re-strengthening as a 1035 mb high builds to the north and the moisture axis over the Big Island shifting westward over the smaller islands. Added instability associated with a broad upper trough over the region combined with breezy northeast trades will lead to a wet trade wind pattern for these areas Wednesday through Thursday.
Rising upper heights and strengthening inversion should lead to a more stable and drier trade wind pattern Friday into the weekend, with a more typical distribution of windward/mauka showers.

Aviation

A high pressure ridge will build in tomorrow far north of the state producing moderate to breezy northeasterly to easterly trade winds blowing across the region for the next few days. A large unstable cloud band, associated with the remnants of a dissipated front, will drift into the islands from the north. Expect enhanced showers with periods of MVFR conditions as these clouds are lifted up and over windward and mountain areas, shower activity will favor the overnight to early morning hours through Thursday.
AIRMET Sierra for mountain obscuration remains in effect for the northeast, east and southeast slopes of the Big Island this evening. Mountain obscurations will likely expand in coverage to the smaller islands through the overnight to early morning hours as additional clouds and showers drift in on the northeasterly trade winds.

Marine

Surface high pressure far north of the islands will advance east and be located northeast of the islands by this weekend. This will produce a tight enough pressure gradient to strengthen and maintain moderate to locally strong trade winds from Wednesday night into next week.
The current medium size, medium period north swell will continue its decline through Wednesday. A small north swell reinforcement is scheduled to arrive Thursday and Friday and hold surf at near head high. North-facing shore surf heights will fall back to average waist to chest high this weekend.
The ongoing slightly elevated small, medium period south swell will generally maintain slightly above summer average waist to chest high south surf through Wednesday. This swell will gradually fall off through the end of the week.
East-facing shore chop will become more rough as upstream trades slightly pick up through the middle of the week.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov