West Side

Today: Breezy. Mostly cloudy with scattered showers. Highs 75 to 81. East winds 15 to 25 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy in the evening, then partly cloudy with isolated showers after midnight. Lows 65 to 71. East winds 10 to 20 mph. Chance of rain 20 percent.

Wednesday: Mostly sunny with isolated showers. Highs around 79. East winds around 10 mph. Chance of rain 20 percent.

South Side

Today: Partly sunny with scattered showers. Highs around 83. Northeast winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Lows 63 to 73. North winds up to 15 mph.

Wednesday: Mostly sunny with isolated showers. Highs around 83. North winds 10 to 15 mph. Chance of rain 20 percent.

North Shore

Today: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 78 near the shore to around 61 near 5000 feet. East winds 15 to 25 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Lows around 68 near the shore to around 50 near 5000 feet. East winds 10 to 25 mph. Chance of rain 50 percent.

Wednesday: Partly sunny with scattered showers. Highs around 78 near the shore to around 62 near 5000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Central Maui

Today: Breezy. Partly sunny with scattered showers. Highs 78 to 84. Northeast winds 10 to 25 mph. Chance of rain 40 percent.

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

Wednesday: Mostly sunny with isolated showers. Highs 79 to 84. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Upcountry

Today: Mostly cloudy. Windy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 58 at the visitor center to around 64 at the summit. Southeast winds 10 to 30 mph decreasing to 10 to 20 mph in the afternoon. Chance of rain 70 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Lows around 45 at the visitor center to around 43 at the summit. Southeast winds 10 to 20 mph. Chance of rain 50 percent.

Wednesday: Partly sunny with isolated showers. Highs around 59 at the visitor center to around 65 at the summit. Southeast winds up to 10 mph. Chance of rain 20 percent.

East Maui

Today: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 78 near the shore to around 61 near 5000 feet. East winds 15 to 25 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Lows around 68 near the shore to around 50 near 5000 feet. East winds 10 to 25 mph. Chance of rain 50 percent.

Wednesday: Partly sunny with scattered showers. Highs around 78 near the shore to around 62 near 5000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Lanai City

Today: Mostly cloudy with scattered showers. Highs 70 to 78. East winds 10 to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Lows around 64. East winds up to 15 mph.

Wednesday: Mostly sunny with isolated showers. Highs 70 to 77. Light winds. Chance of rain 20 percent.

Kaunakakai

Today: Breezy. Partly sunny with scattered showers. Highs 66 to 83. East winds 15 to 25 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Breezy. Lows 56 to 71. East winds 10 to 20 mph.

Wednesday: Mostly sunny with isolated showers. Highs 67 to 83. East winds up to 10 mph in the morning becoming light. Chance of rain 20 percent.

Detailed Forecast

Synopsis

An upper-level low and associated surface trough remain west of the islands and will move southwestward further away from the state in the next day or so. As the low meanders away, it will begin to weaken, greatly decreasing thunderstorms and heavy rain for the Hawaiian Islands. Light winds will develop during the second half of the week allowing for sea breezes to develop, limiting only light shower activity at times.

Discussion

An upper-level low and associated surface trough west of the islands will slowly meander southwestward over the next day or so, weakening as it does, greatly decreasing thunderstorms and heavy rainfall for the Hawaiian Islands. Because of this, have opted to expire the Flood Watch across the state. Shortly thereafter, upper-level ridging will move in its wake by the latter half of the week, returning some sense of stability to the islands, and maintaining slightly cooler and drier conditions through the weekend.
Additionally, have opted to downgrade the Winter Storm Warning for the Big Island Summits to an Winter Weather Advisory, persisting through midnight Wednesday as snow trends have fallen below warning criteria. Have also opted to expiring the Wind Advisory, also for the Summits, as latest observations have fallen below thresholds as well.
Furthermore, the wind regime throughout the weekend will trend lighter across the state, shifting to a more land-sea breeze pattern. In such a pattern, island heating will develop sea breezes each day, and overnight cooling will drive downsloping land breezes each night. During the day, sea breezes will enhance leeward and interior region shower activity, while land breezes overnight will clear the night skies and limit shower activity.
Long range model guidance for early next week supports a weak upper-level trough escorting a surface frontal boundary through much of the state. Given how far out this event is, confidence is low. However, if this were to occur, it would bring periods of enhanced shower activity, with total precipitable water (PW) upwards of two standard deviations above average. Further analysis will be needed closer to date to detail the events more clearly.

Aviation

A trough west of the state will continue to bring numerous showers to windward portions of the Big Island and Kauai and scattered showers elsewhere. Some of the more robust activity may bring brief periods of MVFR ceilings and visibility. Conditions will gradually improve throughout the day as the trough moves to the southwest, away from the islands. Moderate to strong easterly flow will bring tempo moderate turbulence above 8000 feet today, though winds and associated turbulence are expected to slowly decrease as the day progresses.
AIRMET SIERRA remains in effect for Kauai and windward portions of the Big Island above 2000 feet for mountain obscuration due low clouds and showers.
AIRMET TANGO remains in effect for moderate turb due to the moderate to strong easterly winds.
AIRMET ZULU remains in effect for moderate rime icing across the state, but will likely be trimmed down as the mid and upper level clouds and moisture become less widespread.

Marine

A trough west of Hawaii will shift westward allowing a ridge to build north of the region today. The threat of heavy showers and thunderstorms will diminish through this afternoon. Strong to near gale force east to southeast winds will gradually ease today becoming gentle to locally fresh speeds Wednesday. A front approaching the state from the northwest will further ease wind speeds to light to moderate Thursday. The frontal boundary will weaken as it enters to coastal waters Friday and dissipate near the central islands by Saturday. Brief moderate to fresh northerly winds will fill in behind the front but become light to gentle speeds Saturday as another stronger front approaches the state from the northwest Sunday, veering winds more southerly and gradually becoming more moderate before pushing south over the island chain next week.
A Small Craft Advisory (SCA) for both winds and seas remains in effect for the all coastal waters through early Wednesday morning. Wind and sea conditions will drop below advisory thresholds Wednesday through the remainder of the week as the trough moves further west and away from the islands.
A moderate, medium period, north northeast (040-060 degree) swell will veer more easterly and decline today. A small, long period, northwest (310 degree) swell will build late tonight, peak Wednesday and slowly decline through Friday. Forerunners for the next significant large, long period north northwest swell (330 degree) is expected to arrive Friday night and peak Saturday. This swell will likely produce warning surf along exposed north and west facing shores. Seas will build above SCA criteria during this time for most waters. Another, large to extra large, north northwest swell may fill in early next week with surf heights peaking well into warning levels.
A High Surf Advisory remains in effect for exposed east facing shores through tonight due to the combination of the northeast swell mentioned above and rough easterly swell generated by the local and upstream easterly winds. Surf will drop below advisory levels Wednesday.
The Coastal Flood Statement has been canceled. Most tide gauges show peak water levels have dropped near to below minor flooding levels during peak tides Monday and will continue to trend below minor flooding levels with the peak high tide early this morning.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 AM HST Wednesday for Olomana, Kauai East, Kauai South, East Honolulu, Koolau Windward, Molokai Windward, Molokai Southeast, Windward Haleakala, Kipahulu, South Haleakala, Big Island Southeast, Big Island East, Big Island North.
Winter Weather Advisory until midnight HST Wednesday night for Big Island Summits.
Small Craft Advisory until 6 AM HST Wednesday for all Hawaiian waters,

Data Courtesy of NOAA.gov