West Side

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs 76 to 81. West winds up to 10 mph. Chance of rain 30 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Haze through the night. Lows 65 to 71. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs 77 to 82. Light winds becoming north up to 10 mph in the afternoon. Chance of rain 20 percent.

South Side

Today: Mostly sunny in the morning, then mostly cloudy with isolated showers in the afternoon. Haze through the day. Highs around 84. Light winds becoming southwest up to 10 mph in the afternoon. Chance of rain 20 percent.

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Haze through the night. Lows 64 to 74. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs around 85. Light winds becoming north up to 10 mph in the afternoon. Chance of rain 20 percent.

North Shore

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs 77 to 83 near the shore to around 66 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with isolated showers. Haze. Lows around 68 near the shore to around 50 near 5000 feet. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs around 80 near the shore to around 66 near 5000 feet. East winds up to 10 mph. Chance of rain 30 percent.

Central Maui

Today: Mostly sunny in the morning, then mostly cloudy with isolated showers in the afternoon. Haze through the day. Highs 80 to 85. Light winds. Chance of rain 20 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Haze through the night. Lows around 66. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs 80 to 86. North winds up to 10 mph. Chance of rain 20 percent.

Upcountry

Today: Mostly cloudy. Isolated showers and snow showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs around 61 at the visitor center to around 70 at the summit. Light winds. Chance of snow 50 percent.

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Haze through the night. Lows around 45 at the visitor center to around 47 at the summit. Northeast winds up to 10 mph. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs around 61 at the visitor center to around 67 at the summit. Northeast winds up to 10 mph. Chance of rain 20 percent.

East Maui

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs 77 to 83 near the shore to around 66 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with isolated showers. Haze. Lows around 68 near the shore to around 50 near 5000 feet. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs around 80 near the shore to around 66 near 5000 feet. East winds up to 10 mph. Chance of rain 30 percent.

Lanai City

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs 71 to 78. West winds up to 10 mph. Chance of rain 30 percent.

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Haze through the night. Lows around 63. Light winds. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs 72 to 79. Light winds. Chance of rain 20 percent.

Kaunakakai

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Haze through the day. Highs 68 to 83. West winds up to 10 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Haze through the night. Lows 55 to 71. Southeast winds up to 10 mph in the evening becoming light. Chance of rain 20 percent.

Thursday: Partly sunny with isolated showers. Haze. Highs 69 to 84. Light winds. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Rain chances will steadily increase through the week especially over the western half of the state as a frontal boundary moves over Kauai and stalls near Oahu Thursday into Friday. Breezy to locally strong trade winds should return on Friday with a showery trade wind pattern expected through the weekend. Once again, the trade wind showers should be most frequent over the western half of the state.

Discussion

A weak high pressure system northwest of the state is generating light to moderate south to southeasterly winds. Wind speeds are expected to ease today as the high weakens and shifts eastward and a front approaches from the west. Expect seabreezes to develop during the day allowing clouds and showers to build up over leeward and interior areas. Land breezes will develop shortly after sunset clearing low clouds and showers, especially over the eastern half of the state. Vog will be more widespread today. Isolated thunderstorms have been added to the coastal waters northwest of Kauai today as a broad active rainband associated with the front inches closer, although confidence is low. High resolution model guidance shows an area of convergence ahead of the front that could create some scattered showers over the central islands later this afternoon. In addition, could see an uptick in showers along coastlines exposed to southeast flow around Big Island and Maui County as an area of low level clouds with embedded showers moves through. Meanwhile the leading edge of the broad rainband will approach Kauai today becoming disorganized that could generate widely scattered heavier showers. The tail end of the rainband looks to be more organized as it moves over Kauai Thursday. There could be some localized nuisance flooding or ponding concerns later today into Thursday as winds ease, allowing for any moderate to locally heavy showers to persist longer over one area, especially for north Kauai.
The frontal boundary is expected to weaken and stall somewhere around Kauai or Oahu on Friday allowing breezy to locally strong trade winds to return. Lingering moisture and upper level instability will help generate a showery trade wind pattern across the state over the weekend and into early next week. The greatest moisture will once again continue to be across the western half of the state, especially Kauai. Vog should be swept southwest of the state as trades returns.

Aviation

Moderate southerly winds will continue over the western half of the state as a cold front approaches from the northwest. Expect an uptick in shower activity across Kauai and Oahu as moisture streams in from the south ahead of the front, with periods of MVFR likely with the heavier showers.
The eastern half of the state will see moderate to locally breezy southeasterly winds continue, with localized sea breezes in sheltered areas. Conditions should remain mostly VFR.
No AIRMETs are currently in effect.
All areas will continue to see some Vog due to the ongoing eruption of Kilauea. However, Vog is not expected to impact visibilities enough to warrant a mention in any TAF.

Marine

A cold front, slowly approaching the islands from the west, will maintain breezy southeasterly flow across the eastern portion of the state and light to moderate southerly flow elsewhere. Instability aloft, ahead of the front, will lead to isolated thunderstorms west of Kauai by this afternoon. A Small Craft Advisory (SCA) has been extended through this afternoon for waters around the Big Island for local wind acceleration around and along the parallel coastlines to the wind direction. The front should move across Kauai and near Oahu Friday before dissipating. Expect moderate to locally strong northeast trades to develop this weekend and persist into early next week.
A small west- northwest swell will maintain small surf along north and west facing shores today and Thursday. A moderate north- northwest (330-350) swell is expected to arrive on Friday and could produce advisory level surf. A large to extra large, long period, north to north- north west (340-360) swell is forecast to build this weekend and could likely produce warning level surf along north facing shores with advisory level surf across west and east facing shores. This swell, aside from being hazardous to small craft, could generate harbor surges along north facing bays and inlets.
Surf along south facing shores will remain low through this weekend with mainly background energy dominating.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST this evening for Big Island Windward Waters, Big Island Leeward Waters.

Data Courtesy of NOAA.gov