West Side

Today: Sunny. Isolated showers in the morning. Highs 80 to 86. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 68 to 75. East winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 81 to 86. Northeast winds around 10 mph. Chance of rain 50 percent.

South Side

Today: Sunny and breezy. Highs around 87. North winds up to 15 mph increasing to 15 to 20 mph in the afternoon.

Tonight: Mostly clear. Isolated showers in the evening. Lows 70 to 77. North winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs around 88. North winds 10 to 15 mph. Chance of rain 40 percent.

North Shore

Today: Mostly sunny with scattered showers. Highs 80 to 86 near the shore to around 67 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with scattered showers. Lows around 73 near the shore to around 54 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 50 percent.

Sunday: Mostly cloudy with numerous showers. Highs 80 to 86 near the shore to around 67 near 5000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Central Maui

Today: Sunny and breezy. Highs 81 to 88. Northeast winds up to 20 mph increasing to 15 to 20 mph in the afternoon.

Tonight: Partly cloudy with isolated showers. Lows around 71. Northeast winds up to 15 mph. Chance of rain 20 percent.

Sunday: Partly sunny with scattered showers. Highs 82 to 89. Northeast winds around 10 mph. Chance of rain 50 percent.

Upcountry

Today: Partly sunny with isolated showers. Highs around 65 at the visitor center to around 71 at the summit. Light winds. Chance of rain 20 percent.

Tonight: Partly cloudy with scattered showers. Lows around 51 at the visitor center to around 47 at the summit. Light winds. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs around 65 at the visitor center to around 68 at the summit. Light winds. Chance of rain 50 percent.

East Maui

Today: Mostly sunny with scattered showers. Highs 80 to 86 near the shore to around 67 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with scattered showers. Lows around 73 near the shore to around 54 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 50 percent.

Sunday: Mostly cloudy with numerous showers. Highs 80 to 86 near the shore to around 67 near 5000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Lanai City

Today: Mostly sunny. Breezy. Highs 72 to 81. Northeast winds up to 15 mph increasing to 10 to 20 mph in the afternoon.

Tonight: Partly cloudy. Breezy. Lows around 66. Northeast winds 10 to 20 mph.

Sunday: Mostly sunny. Isolated showers in the afternoon. Highs 74 to 82. Light winds. Chance of rain 20 percent.

Kaunakakai

Today: Sunny. Highs 73 to 89. Northeast winds up to 15 mph.

Tonight: Mostly clear. Lows 61 to 74. Northeast winds 10 to 15 mph shifting to the east after midnight.

Sunday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 74 to 90. Northeast winds around 10 mph. Chance of rain 40 percent.

Detailed Forecast

Synopsis

A surface trough approaching the state from the east will result in gentle to moderate trade winds this weekend. The trough will bring an uptick in clouds and showers to the windward and mauka areas. Expect trades to strengthen to moderate levels Tuesday or Wednesday.

Discussion

A surface trough to the east of the islands continues to advance towards the islands this morning. The trough will likely dissipate before it reaches the islands, however remnant moisture from the trough will continue to be carried into the islands on the trade wind flow. This will more than likely increase the clouds and showers over the windward side of the Big Island this afternoon, and spread to the other islands later tonight and Sunday.
There is good model agreement with high pressure building back in to the northeast of the state early next week, which will allow the trade winds to strengthen back to moderate to locally breezy levels by midweek. However, there remains some uncertainty with regards to the potential for tropical development south of Hawaii, which could factor into how much the trades strengthen. At the same time, a drier airmass is expected to return to the islands.

Aviation

A surface trough to the east of the state will continue to move towards the islands, which will help to weaken trades to gentle to moderate levels for the weekend. While most of the state will continue to experience a relatively dry and stable airmass today, the trough will likely bring an increase in clouds and some showers to the Big Island this afternoon, and other parts of the state tonight and Sunday.
Predominately VFR conditions are expected to prevail, however brief periods of isolated showers remain possible over the windward areas of the islands. As the trough moves over the islands, some MVFR conditions are possible over the windward sides of the islands with the clouds and showers.
There currently are no AIRMETs in effect, and not expecting any to be issued today.

Marine

Weak high pressure to the northeast of the state will allow gentle to locally fresh trade winds through Monday. Trade winds will gradually strengthen Tuesday to moderate to locally strong levels as high pressure restrengthens to the northeast and also a potential for a tropical disturbance tracking south of the waters.
South facing shores will remain small through the weekend with mainly medium period background energy. A storm force low east of New Zealand is producing seas up to 40 feet per JSON satellite observations, likely impacting the islands during the second half of next week. Confidence has increased that this low will generate a moderate to large long period south swell that may approach or exceeds the High Surf Advisory threshold as it peaks.
East facing shores will gradually decline this weekend as trade winds weaken locally and upstream of the state. Flat to tiny surf expected along north facing shores through the forecast period.

Fire weather

Most of the state will remain in a dry and stable airmass today, however an surface trough approaching from the east will bring with it an uptick in clouds and showers. Winds are expected to weaken to gentle to moderate levels today as the trough disrupts the flow. The shallow area of moisture associated with the trough should bring an increase in humidity late Saturday into Monday, further decreasing fire weather concerns. Trade winds are expected to restrengthen Tuesday or Wednesday, with developing dry conditions reestablishing, which may result in elevated fire weather concerns.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov