Photo Credit: Tyler Rooke

West Side

Today: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 84 to 91. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Partly cloudy with scattered showers. Lows 68 to 75. Northeast winds 10 to 15 mph shifting to the east after midnight. Chance of rain 50 percent.

Sunday: Mostly sunny. Breezy. Scattered showers in the morning. Highs 85 to 92. East winds 10 to 20 mph. Chance of rain 40 percent.

South Side

Today: Mostly sunny. Scattered showers in the afternoon. Highs 88 to 93. North winds up to 15 mph. Chance of rain 30 percent.

Tonight: Mostly clear. Isolated showers after midnight. Lows around 69. North winds up to 15 mph. Chance of rain 20 percent.

Sunday: Sunny and breezy. Highs 89 to 94. Northeast winds up to 20 mph.

North Shore

Today: Mostly cloudy. Breezy. Occasional showers in the morning, then scattered showers in the afternoon. Highs 83 to 89 near the shore to 63 to 68 near 5000 feet. East winds up to 20 mph. Chance of rain 80 percent.

Tonight: Mostly cloudy. Breezy. Showers likely in the evening, then occasional showers after midnight. Lows 65 to 72 near the shore to around 53 near 5000 feet. East winds up to 20 mph. Chance of rain 90 percent.

Sunday: Breezy. Partly sunny with showers likely in the morning, then mostly sunny with isolated showers in the afternoon. Highs 84 to 90 near the shore to 64 to 70 near 5000 feet. East winds 10 to 20 mph decreasing to up to 20 mph in the afternoon. Chance of rain 70 percent.

Central Maui

Today: Partly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 91. Northeast winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 67 to 73. Northeast winds 10 to 15 mph decreasing to up to 15 mph after midnight. Chance of rain 20 percent.

Sunday: Mostly sunny. Breezy. Isolated showers in the morning. Highs around 92. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Upcountry

Today: Partly sunny with showers likely in the morning, then mostly sunny with scattered showers in the afternoon. Highs around 60 at the visitor center to around 56 at the summit. East winds up to 15 mph. Chance of rain 70 percent.

Tonight: Partly cloudy with scattered showers. Lows around 48 at the visitor center to around 44 at the summit. East winds up to 15 mph. Chance of rain 50 percent.

Sunday: Sunny. Scattered showers in the morning. Highs around 62 at the visitor center to around 58 at the summit. East winds up to 15 mph. Chance of rain 50 percent.

East Maui

Today: Mostly cloudy. Breezy. Occasional showers in the morning, then scattered showers in the afternoon. Highs 83 to 89 near the shore to 63 to 68 near 5000 feet. East winds up to 20 mph. Chance of rain 80 percent.

Tonight: Mostly cloudy. Breezy. Showers likely in the evening, then occasional showers after midnight. Lows 65 to 72 near the shore to around 53 near 5000 feet. East winds up to 20 mph. Chance of rain 90 percent.

Sunday: Breezy. Partly sunny with showers likely in the morning, then mostly sunny with isolated showers in the afternoon. Highs 84 to 90 near the shore to 64 to 70 near 5000 feet. East winds 10 to 20 mph decreasing to up to 20 mph in the afternoon. Chance of rain 70 percent.

Lanai City

Today: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 74 to 83. Northeast winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy. Breezy. Isolated showers in the evening. Lows around 69. Northeast winds 10 to 20 mph decreasing to up to 15 mph after midnight. Chance of rain 20 percent.

Sunday: Mostly sunny. Breezy. Isolated showers in the afternoon. Highs 75 to 84. Northeast winds up to 15 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 20 percent.

Kaunakakai

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 79 to 89. East winds up to 15 mph shifting to the northeast in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 64 to 75. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 79 to 89. East winds 10 to 20 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Light to moderate trades will prevail today, allowing localized sea breezes to develop in the more sheltered leeward areas. An area of enhanced moisture will move from east to west through the islands today through early Sunday, bringing showery conditions to many windward areas at times, and sending some showers into leeward communities as well. Drier conditions and moderate trades will return on Sunday and hold through Sunday night. Another round of increased showers appears to move from east to west through the islands Labor Day through early Tuesday, with drier more typical trade wind weather then returning Tuesday afternoon through late next week.

Discussion

Currently at the surface, a weak west to east oriented surface ridge is positioned around 700 miles north of Kauai, while closer to home, a weak west-southwest to east-northeast oriented trough of low pressure is located around 250 miles north of Honolulu. The ridging continues to be the more dominant weather feature, maintaining moderate trade winds in the unsheltered areas early this morning. Infrared satellite imagery shows mostly cloudy conditions in windward areas, with partly cloudy conditions in many leeward locales. Radar imagery shows numerous showers moving into windward areas, with quite a few of these showers spreading into leeward communities as well. Main short term focus revolves around trade wind trends and rain chances during the next few days.
The trough north of the islands will remain nearly stationary today, before shifting westward tonight and Sunday. Meanwhile, surface ridging will remain the dominant weather feature to the north of the islands during the next 7 days. Light to moderate trades will prevail today, with localized sea breezes in the more sheltered leeward areas. The trades should strengthen back to moderate levels tonight and Sunday, then hold steady at this level through the middle of next week. The trades could trend downward again late next week.
As for the remaining weather details, an area of deeper moisture over and just upstream of the eastern and central islands, will continue to slide westward today, bringing showery conditions to windward areas and quite a bit of leeward spillover as well as it moves through. Trade showers should trend downward tonight over the western islands, but some lingering deep moisture could keep windward areas of Maui County and the Big Island a bit showery through early Sunday morning. A drier trade wind pattern should then return statewide from mid morning Sunday through Sunday night. The next area of deeper moisture then appears to slide from east to west through the islands Labor Day through early Tuesday, with a return to a drier more typical trade wind pattern Tuesday afternoon through late next week.

Aviation

Early this morning, an area of enhanced moisture stretching from the Kauai Channel to Maui has increased showers and low clouds along windward slopes and coasts. MVFR conditions have prevailed across north through east sections of Oahu, Molokai, and Maui throughout the night and early morning, with isolated IFR cigs observed as well. AIRMET Sierra remains in effect for tempo mountain obscuration for Oahu and Maui County islands, though this may need to be expanded to include Kauai as well later this morning as moisture spreads westward.
Light to moderate trade winds will persist across the state today. In addition to scattered shower activity across windward locations, leeward sea breezes will focus afternoon and evening cumulus over island interiors as well before diminishing this evening and tonight.

Marine

Moderate to fresh easterly trades will persist through tonight, then briefly strengthen into the fresh to strong category Sunday into early next week as high pressure builds to the north.
Surf along south facing shores will remain small through next week with mainly reinforcing shots of south and south-southwest background level swells moving through. The next small source will arrive tonight into Sunday out of the south, that will lead to an upward trend that should hold through Monday before easing. For the extended, a decent south-southwest swell could arrive locally next weekend (around the 10th), depending on how the source evolves as it passes south of the Tasman Sea and New Zealand this weekend.
Surf along north facing shores will remain small through next week, with mainly the small northerly (low- to medium-period) swells continuing due to the deep troughing and systems in/near the Gulf of Alaska. Guidance does show a compact low moving eastward over the western Aleutians this weekend with a batch of fresh breezes setting up within the 330-340 directional band relative to the islands. If this materializes, a small north- northwest swell could arrive by next Thursday.
Surf along east facing shores will remain well below the seasonal average into next week.

HFO Watches/Warnings/Advisories

None.

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

Check out their Maui Helicopter Tours today!

Data Courtesy of NOAA.gov