West Side

Today: 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.

Tonight: 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.

Thursday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 76 to 81. East winds 10 to 20 mph. Chance of rain 20 percent.

South Side

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

Tonight: 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.

Thursday: Mostly sunny. Breezy. Highs around 85. Northeast winds 10 to 20 mph.

North Shore

Today: 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.

Tonight: 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.

Thursday: Partly sunny with scattered showers. Highs 76 to 82 near the shore to around 65 near 5000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Central Maui

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

Tonight: 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.

Thursday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 79 to 86. East winds 10 to 25 mph. Chance of rain 20 percent.

Upcountry

Today: 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.

Tonight: 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.

Thursday: Breezy. Partly sunny with scattered showers. Highs around 60 at the visitor center to around 62 at the summit. East winds 10 to 20 mph. Chance of rain 50 percent.

East Maui

Today: 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.

Tonight: 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.

Thursday: Partly sunny with scattered showers. Highs 76 to 82 near the shore to around 65 near 5000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Lanai City

Today: 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.

Tonight: 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.

Thursday: Mostly sunny. Breezy. Highs 72 to 79. Northeast winds 15 to 25 mph.

Kaunakakai

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

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

Thursday: Mostly sunny. Breezy. Scattered showers in the morning. Highs 68 to 84. East winds 15 to 25 mph. Chance of rain 40 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 upper disturbance in the area 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 stalled across the Big Island this morning, which has led to an uptick in shower coverage, particularly across windward sections of the Big Island. Observations reflect this at the rain gauges, showing up to three quarters of an inch of rainfall overnight in this area. This lingering moisture boundary combined with an elevated inversion will support the potential for showery conditions persisting this morning over and around the Big Island. Elsewhere across the state, expect the dry and stable conditions to continue with only spotty windward showers.
Later today through the remainder 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 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 far north of the state today with 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 morning. These conditions will diminish later this morning.

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 downstream pressure gradient in maintaining moderate to locally strong trade winds from tonight through next week.
The ongoing moderate size, medium period north swell will continue its decline through the day. A moderate size, smaller period north turning northeast swell is scheduled to arrive tonight and move through Thursday. This will hold near head high to slightly above head high surf in place. North-facing shore surf heights will fall back to average waist to chest high over the weekend.
The ongoing slightly elevated small, medium period south swell will generally maintain slightly above summer average waist to chest high south surf through the day. 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 the next couple of days.

HFO Watches/Warnings/Advisories

Small Craft Advisory from noon today to 6 PM HST Thursday for Kauai Northwest Waters, Kauai Windward Waters, Kauai Leeward Waters, Kauai Channel, Oahu Windward Waters, Oahu Leeward Waters, Kaiwi Channel, Maui County Windward Waters, Maalaea Bay, Pailolo Channel, Alenuihaha Channel.

Data Courtesy of NOAA.gov