Photo Credit: Tyler Rooke

West Side

Today: Windy. Mostly sunny with isolated showers. Highs 75 to 82. Northeast winds 20 to 30 mph with gusts to 50 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Windy. Scattered showers in the evening, then isolated showers after midnight. Lows 62 to 68. Northeast winds 10 to 30 mph with gusts to 50 mph. Chance of rain 50 percent.

Wednesday: Breezy. Mostly sunny with isolated showers. Highs 75 to 82. East winds 10 to 20 mph. Chance of rain 20 percent.

South Side

Today: Sunny and windy. Highs around 83. Northeast winds 15 to 30 mph with gusts to 50 mph.

Tonight: Mostly clear. Windy. Lows around 64. Northeast winds 10 to 30 mph with gusts to 50 mph.

Wednesday: Sunny. Highs around 83. North winds 10 to 15 mph.

North Shore

Today: Partly sunny. Windy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 81 near the shore to around 54 near 5000 feet. East winds 10 to 30 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Windy. Scattered showers in the evening, then numerous showers after midnight. Lows 62 to 67 near the shore to around 49 near 5000 feet. East winds 10 to 30 mph. Chance of rain 70 percent.

Wednesday: Partly sunny. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 81 near the shore to around 54 near 5000 feet. East winds 15 to 20 mph. Chance of rain 70 percent.

Central Maui

Today: Windy. Mostly sunny with isolated showers. Highs 79 to 84. Northeast winds 15 to 30 mph. Chance of rain 20 percent.

Tonight: Breezy. Partly cloudy with isolated showers. Lows around 64. Northeast winds 10 to 25 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 sunny. Windy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 51 to 70. East winds up to 30 mph. Chance of rain 50 percent.

Tonight: Windy. Partly cloudy with scattered showers. Lows 41 to 52. East winds up to 30 mph increasing to 10 to 30 mph after midnight. Chance of rain 50 percent.

Wednesday: Mostly sunny. Windy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 51 to 70. East winds 20 to 30 mph. Chance of rain 50 percent.

East Maui

Today: Partly sunny. Windy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 81 near the shore to around 54 near 5000 feet. East winds 10 to 30 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Windy. Scattered showers in the evening, then numerous showers after midnight. Lows 62 to 67 near the shore to around 49 near 5000 feet. East winds 10 to 30 mph. Chance of rain 70 percent.

Wednesday: Partly sunny. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 81 near the shore to around 54 near 5000 feet. East winds 15 to 20 mph. Chance of rain 70 percent.

Lanai City

Today: Mostly sunny. Windy. Isolated showers in the afternoon. Highs 70 to 77. Northeast winds 20 to 30 mph with gusts to 50 mph. Chance of rain 20 percent.

Tonight: Mostly clear. Windy. Lows around 62. Northeast winds 25 to 30 mph decreasing to 15 to 30 mph after midnight. Gusts up to 50 mph.

Wednesday: Sunny and breezy. Isolated showers in the afternoon. Highs 70 to 77. East winds 10 to 20 mph. Chance of rain 20 percent.

Kaunakakai

Today: Windy. Mostly sunny with isolated showers. Highs 74 to 80. Northeast winds 10 to 30 mph. Chance of rain 20 percent.

Tonight: Windy. Partly cloudy with isolated showers. Lows 64 to 72. Northeast winds 15 to 30 mph. Chance of rain 20 percent.

Wednesday: Breezy. Mostly sunny with isolated showers. Highs 74 to 80. East winds 20 to 25 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Drier trends are forecast for much of this week, as a strong high pressure system north of the islands keeps breezy to windy trade winds blowing through Thursday. Trade wind speeds show decreasing trends to more moderate levels from Friday through the weekend with expanding daytime sea breezes over terrain sheltered western slopes of each island. An upper level low moving into the Hawaii Region from the northwest direction may enhance shower activity across the state from Saturday into early next week.

Discussion

The satellite imagery this morning shows a few bands of clouds riding into each island on the trade winds. Higher pressure building in quickly from the north this morning will lower stable temperature inversion heights aloft and decrease cloud cover and rain shower activity across the state. A few thunderstorms are developing along the Big Island leeward wind convergence plume roughly 100 miles west of Kona. These thunderstorms in the offshore waters should diminish later today.
A strong high pressure system building north of the Hawaiian Islands will produce strong and gusty winds across the region for through Wednesday. These strong winds will peak at wind advisory levels today through early Wednesday morning over terrain favored windy areas of Maui County and the Big Island. Lower temperature inversion heights aloft will tend to compress the lower level boundary layer and increase these wind speeds over and downwind of island mountains; mountain passes will also see a sharp increase in these wind speeds. Stronger winds will continue on Wednesday, probably just below Wind Advisory thresholds for all islands. Wind speeds will trend noticeably lower on Thursday with a more significant decrease in trade wind speeds from Friday into the weekend as a low pressure system approaches the state from the northwest direction.
Long range forecast guidance continues to show decreasing wind trends by this weekend to more moderate levels. These lighter large scale east-southeasterly winds will allow local scale sea breezes to expand in coverage over terrain sheltered western mountain slopes of each island. A cold front approaching the islands from the northwest direction will stall out a few hundred miles west of Kauai and form an upper level cut off low by Saturday. This unstable upper level cold core low may get close enough to the islands for unstable convergence bands to set up in the east-southeasterly wind flow. Island convergence plumes forming to the lee of island mountains may also enhance shower activity even further. If these unstable cloud bands develop they may bring periods of moderate to locally heavy rain showers to portions of affected islands. In any case the eastern to southeastern slopes of the Big Island should also see an increase in shower activity by this weekend. These unsettled weather conditions may last into early next week.
Enhanced rainfall amounts from Saturday into early next week will be highly dependent upon how close the unstable upper low sets up relative to each island. Western islands will therefore see higher chances for enhanced shower activity during this time period. Stay tuned.

Aviation

Most areas will see prevailing VFR conditions with brief MVFR conditions possible near the Big Island today. Trade wind speeds will ramp up and hold in the breezy to strong range for the next 24 to 36 hours.
AIRMET Sierra for mountain obscuration is currently in effect for north and east facing slopes of the Big Island. These cloudy conditions will improve later this morning.
AIRMET Tango remains in effect for moderate low level turbulence over and downwind of island terrain. This AIRMET is expected to continue over the next several days due to strong winds.

Marine

A strong high pressure cell building far north of the state will maintain strong to gale force winds through early Wednesday morning, then weaken slightly thereafter. Gale Warnings are in effect through early Wednesday morning for Alenuihaha and Pailolo Channels and Maalaea Bay. A Small Craft Advisory for all of the remaining Hawaiian waters will likely be extended into Thursday. Trade winds should continue to weaken slightly and veer towards the east- southeast late this week into this weekend as a trough develops west of the state.
The current small north-northwest swell (340 degree) is expected to steadily decline today and fade out. A moderate long- period north- northwest (330 degree) swell will arrive this evening and peak on Wednesday, producing elevated surf along select north and west facing shores near advisory thresholds. A similar sized long- period west- northwest to northwest swell (300 to 320 degree) is expected to fill in Thursday night and peak on Friday. This swell could once again briefly approach advisory thresholds for select north and west facing shores on Friday and gradually decline over the weekend.
Rough surf will continue along east facing shores over the next several days in response to the persistent strong trade winds over and upstream of the islands. Surf will near High Surf Advisory criteria today into Wednesday morning as trades peak in strength. Surf along south- facing shores will remain small.

HFO Watches/Warnings/Advisories

Wind Advisory from 6 AM this morning to 6 AM HST Wednesday for Lanai Mauka, Kahoolawe, Maui Windward West, Maui Leeward West, Kohala, Lanai Windward, Lanai Leeward, Maui Central Valley North, Maui Central Valley South, South Haleakala, Big Island South, Big Island Southeast, Big Island North.
Small Craft Advisory until 6 AM HST Wednesday for Kauai Northwest Waters, Kauai Windward Waters, Kauai Leeward Waters, Kauai Channel, Oahu Windward Waters, Oahu Leeward Waters, Kaiwi Channel, Maui County Windward Waters, Maui County Leeward Waters, Big Island Windward Waters, Big Island Leeward Waters, Big Island Southeast Waters.
Small Craft Advisory until 6 AM HST early this morning for Maalaea Bay, Pailolo Channel, Alenuihaha Channel.
Gale Warning from 6 AM this morning to 6 AM HST Wednesday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel.

Maui Now Weather is brought to you by Blue Hawaiian Helicopters.

Check out their Maui Helicopter Tours today!

Data Courtesy of NOAA.gov