Photo Credit: Tyler Rooke

West Side

Today: Breezy. Partly sunny with scattered showers. Highs 75 to 86. Northeast winds 10 to 20 mph. Chance of rain 40 percent.

Tonight: Breezy. Partly cloudy with scattered showers in the evening, then cloudy with isolated showers after midnight. Lows 67 to 74. East winds 10 to 20 mph. Chance of rain 40 percent.

Thursday: Breezy. Cloudy with isolated showers. Highs 75 to 86. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

South Side

Today: Breezy. Mostly sunny with isolated showers. Highs around 87. North winds 15 to 20 mph. Chance of rain 20 percent.

Tonight: Partly cloudy in the evening then becoming cloudy. Breezy. Isolated showers. Lows 67 to 73. North winds 10 to 20 mph. Chance of rain 20 percent.

Thursday: Breezy. Cloudy with isolated showers. Highs around 86. North winds 10 to 20 mph. Chance of rain 20 percent.

North Shore

Today: Breezy. Mostly cloudy with occasional showers. Highs 74 to 82 near the shore to around 63 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Tonight: Breezy. Mostly cloudy with occasional showers. Lows around 69 near the shore to 47 to 53 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Thursday: Cloudy and breezy. Occasional showers in the morning, then showers likely in the afternoon. Highs 74 to 82 near the shore to around 63 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Central Maui

Today: Mostly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 80 to 87. Northeast winds around 20 mph. Chance of rain 50 percent.

Tonight: Partly cloudy in the evening then becoming cloudy. Isolated showers. Lows 66 to 71. Northeast winds around 15 mph. Chance of rain 20 percent.

Thursday: Breezy. Cloudy with isolated showers. Highs 79 to 86. Northeast winds 15 to 20 mph. Chance of rain 20 percent.

Upcountry

Today: Mostly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs around 59 at the visitor center to around 54 at the summit. East winds 10 to 25 mph. Chance of rain 50 percent.

Tonight: Partly cloudy in the evening then becoming cloudy. Breezy. Scattered showers. Lows around 46 at the visitor center to around 43 at the summit. East winds 10 to 25 mph. Chance of rain 50 percent.

Thursday: Breezy. Cloudy with scattered showers. Highs around 59 at the visitor center to around 55 at the summit. East winds 10 to 20 mph. Chance of rain 50 percent.

East Maui

Today: Breezy. Mostly cloudy with occasional showers. Highs 74 to 82 near the shore to around 63 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Tonight: Breezy. Mostly cloudy with occasional showers. Lows around 69 near the shore to 47 to 53 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Thursday: Cloudy and breezy. Occasional showers in the morning, then showers likely in the afternoon. Highs 74 to 82 near the shore to around 63 near 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Lanai City

Today: Windy. Mostly sunny with isolated showers. Highs 72 to 80. Northeast winds 15 to 30 mph. Chance of rain 20 percent.

Tonight: Partly cloudy in the evening then becoming cloudy. Breezy. Isolated showers. Lows around 64. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Thursday: Breezy. Cloudy with isolated showers. Highs 71 to 80. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Kaunakakai

Today: Breezy. Mostly sunny with isolated showers. Highs 66 to 86. East winds 15 to 20 mph. Chance of rain 20 percent.

Tonight: Partly cloudy in the evening then becoming cloudy. Isolated showers. Lows 57 to 73. East winds 10 to 15 mph. Chance of rain 20 percent.

Thursday: Cloudy with isolated showers. Highs 66 to 85. East winds around 15 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

A breezy and wet trade wind weather will continue the next couple of days, with a few brief heavy downpours, and possibly a thunderstorm, today. Showers will be focused over windward areas, but a few will occasionally drift to leeward areas. Thickening high clouds are expected statewide from tonight through Friday. A trend toward lighter trade winds, with fewer clouds and showers, is anticipated over the weekend.

Discussion

A wet trade wind weather pattern will remain in place the next couple of days, as a nearby low aloft continues to destabilize the island atmosphere. Showers will primarily soak windward areas, but breezy to locally strong trade winds will allow a few showers to drift over leeward communities on the smaller islands. Daytime heating of the Big Island's leeward slopes will help to fuel fairly widespread afternoon showers, and possibly a thunderstorm today.
A ridge of high pressure well N of the islands will support breezy to locally strong trade winds into the weekend. A front approaching from the NW over the weekend will force the ridge southward, leading to some weakening of the winds, while also veering them to the ESE on Sunday. Light to moderate easterly trade winds are then expected to continue into early next week, favoring a SE direction over the Kauai end of the chain.
A closed low aloft now centered just WSW of Kauai has been moving toward the SW at 20 mph over the past 12 hours, and has been sparking scattered thunderstorms, mainly over Offshore waters S and W of the islands. Layered high clouds have diminished somewhat over the area, but low-level moisture remains sufficiently deep to bring moisture to the Big Island Summits, where temperatures are below freezing, leading to a wintry mix of precipitation. An ongoing Winter Weather Advisory has been extended through today.
As the low aloft wobbles around to the W of the islands the next couple of days, strong divergence aloft to the E of the center will lead to widespread mid- and high-clouds moving over the islands tonight through Friday. The divergence aloft may be able to trigger some briefly heavy showers, and maybe an isolated thunderstorm or two, but it is not expected to lead to widespread destabilization. However, moderate instability will ensure that the trade winds deliver frequent passing showers to windward areas, while a few showers drift leeward.
As the deep-layer trough aloft weakens and moves NE on Saturday, layered high clouds will diminish, and the island atmosphere will gradually stabilize. A mid-level ridge will build over the area from the SW, and PWAT will trend toward normal, so just a few trade wind showers are expected.

Aviation

Breezy and wet trade wind conditions will continue through the 24-hr period, with the best shower coverage remaining over windward and mauka locations. Some showers will be heavy and a few thunderstorms can't be ruled out as an upper disturbance lingers in the area. IFR conditions are expected in and around the heavier showers.
AIRMET Sierra for mountain obscuration will remain in effect for most windward zones.
AIRMET Tango for lee turbulence below 12000 FT will remain in effect for the entire area.

Marine

High pressure north of the state will continue to produce rather strong trade winds across the area over the next several days. A Small Craft Advisory (SCA) is in effect for all Hawaiian Coastal Waters through this afternoon. The combination of strong trades and large northwest and south swells may keep SCA conditions in place across many areas into Thursday. In addition, an upper low over the area has destabilized the local airmass, producing isolated thunderstorms. This low will slowly move west and then lift away allowing for more stability over the weekend.
The current long period northwest swell will hold today, then slowly subside tonight through the end of the week. A High Surf Advisory (HSA) is currently in effect for exposed north and west shores.
The current long period south swell will linger through Thursday then slowly lower through rest of the week. A High Surf Advisory is currently in effect for all south facing shores. Also, a Marine Weather Statement has been issued for the potential for waves breaking in harbor entrances and well as the potential for some harbor surges.
Trade winds over and upwind of the state will continue to produce above normal, short-period surf along east facing shores through Friday then lower slightly over the weekend as trade winds become a bit lighter.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 PM HST Thursday for south facing shores of all islands.
High Surf Advisory until 6 AM HST Thursday for north and west facing shores of Niihau, Kauai, Oahu, and Molokai and for north facing shores of Maui.
Winter Weather Advisory until 6 PM HST this evening for Big Island Summits.
Small Craft Advisory until 6 PM HST this evening for all Hawaiian waters.