West Side

Today: Mostly sunny. Breezy. Isolated showers in the morning. Highs 81 to 87. East winds 15 to 25 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Breezy. Lows 69 to 76. East winds 20 to 25 mph.

Friday: Mostly sunny. Windy. Highs 81 to 87. East winds 20 to 25 mph shifting to the northeast 10 to 30 mph in the afternoon.

South Side

Today: Mostly sunny. Breezy. Highs around 90. Northeast winds up to 20 mph.

Tonight: Mostly clear. Breezy. Lows 69 to 77. Northeast winds up to 20 mph.

Friday: Sunny and breezy. Highs around 90. Northeast winds up to 20 mph increasing to 10 to 25 mph in the afternoon.

North Shore

Today: Breezy. Mostly cloudy with scattered showers. Highs 80 to 86 near the shore to around 68 near 5000 feet. East winds up to 25 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 73 near the shore to around 53 near 5000 feet. Southeast winds up to 20 mph. Chance of rain 40 percent.

Friday: Partly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 86 near the shore to around 68 near 5000 feet. Southeast winds up to 25 mph shifting to the east 10 to 25 mph in the afternoon. Chance of rain 40 percent.

Central Maui

Today: Partly sunny in the morning then becoming mostly sunny. Windy. Highs 82 to 90. East winds 10 to 30 mph.

Tonight: Partly cloudy. Breezy. Lows around 72. East winds 10 to 25 mph.

Friday: Mostly sunny. Windy. Highs 82 to 90. East winds 10 to 30 mph.

Upcountry

Today: Breezy. Mostly sunny with isolated showers in the morning, then partly sunny in the afternoon. Highs around 67 at the visitor center to around 72 at the summit. East winds up to 25 mph. Chance of rain 20 percent.

Tonight: Breezy. Partly cloudy with isolated showers. Lows around 51 at the visitor center to around 49 at the summit. East winds up to 25 mph. Chance of rain 20 percent.

Friday: Mostly sunny. Breezy. Isolated showers in the morning. Highs around 67 at the visitor center to around 71 at the summit. East winds up to 25 mph. Chance of rain 20 percent.

East Maui

Today: Breezy. Mostly cloudy with scattered showers. Highs 80 to 86 near the shore to around 68 near 5000 feet. East winds up to 25 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 73 near the shore to around 53 near 5000 feet. Southeast winds up to 20 mph. Chance of rain 40 percent.

Friday: Partly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 86 near the shore to around 68 near 5000 feet. Southeast winds up to 25 mph shifting to the east 10 to 25 mph in the afternoon. Chance of rain 40 percent.

Lanai City

Today: Mostly sunny in the morning then becoming partly sunny. Breezy. Highs 74 to 83. Northeast winds 10 to 20 mph.

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

Friday: Mostly sunny. Breezy. Highs 74 to 83. Northeast winds 10 to 20 mph.

Kaunakakai

Today: Mostly sunny. Breezy. Highs 74 to 90. East winds 10 to 25 mph.

Tonight: Partly cloudy. Breezy. Lows 62 to 75. East winds 10 to 20 mph.

Friday: Mostly sunny. Breezy. Highs 74 to 90. East winds 10 to 25 mph.

Detailed Forecast

Synopsis

Breezy to locally windy trade winds will continue through the weekend, then gradually ease early next week. Clouds and light showers will focus along windward and mauka areas, particularly overnight and during the early morning hours as a rather dry and stable airmass settles over the state and persists over the next several days.

Discussion

Surface high pressure far north of the state will continue to interact with a series of tropical cyclones passing well south of the island chain to tighten the local pressure gradient and bring breezy to locally windy trade winds across the state over the next couple of days. A Wind Advisory for portions of the Big Island and Maui County has been issued as winds are expected to strengthen through the morning hours and reach low end advisory levels. The morning upper air soundings from Hilo and Lihue both showed a strong inversion heights around 5000 feet, indicative of the stable airmass overhead that could also help induce breezy. These stable, breezy to locally windy trades will focus clouds and light showers over windward and mauka areas as batches of shallow moisture filter across the region, particularly during the overnight to early morning hours. The strengthening trades may also help to carry over light showers into some leeward areas at times.
As the tropical cyclones to our south weaken and move further away early next week, the local pressure gradient may relax some, allowing the trades to ease slightly. However, other than this slight decrease in wind speeds, a typical trade wind weather pattern should continue through Tuesday.

Aviation

Breezy to locally windy trade winds will make for prevailing VFR conditions. Brief periods of MVFR conditions are possible with low clouds and showers facing windward and mountain areas in the overnight to early morning hours.
The trade winds will be strong enough to keep AIRMET Tango in place for the foreseeable future. AIRMET Sierra has been cancelled as low cloud ceilings have diminished.

Marine

High pressure far northeast of the state will help generate fresh to locally near gale trades for the remainder of the work week. By this weekend, the high will strengthen slightly and bring more widespread strong trades to the local waters. A Small Craft Advisory (SCA) remains in effect for most marine zones surrounding Maui and the Big Island through tonight, but expect to extended into Friday. Additional zones will likely be added to the SCA this weekend due to the increasing winds. Trades then begin to weaken early next week as the aforementioned high drifts further east.
Tropical Storm Iona continues to track to the west, far southwest of the main Hawaiian Islands. Additional tropical cyclone development is possible far southeast of Hawaii over the next day or so, but expecting little to no impact on our local waters.
Long period forerunners from the south swell event have already begun to show up at our local nearshore buoys. This swell will continue to build in across the islands through this afternoon, peak late today through Friday, then slowly lower thereafter. This first south swell event will be followed by another long period south swell early next week. As a result, a High Surf Advisory remains in effect for the south facing shores of all islands through today, but the advisory may need to be extended in time or upgraded to a warning depending on buoy observations towards the peak of the event.
East shore surf will remain elevated and choppy due to locally strong trade winds through this weekend. This will be followed by a decline early next week as trades weaken.
Flat summer conditions along north facing shores may be interrupted late this weekend by a small long period northwest swell from Typhoon Krosa, currently in the western Pacific.

Fire weather

Winds speeds are expected to reach 20 mph along some leeward locations by this afternoon under dry and stable conditions. Borderline critical conditions are still expected today. The limiting factor is how low the relative humidity values will reach today into the weekend as an area of moisture slowly exits west of the state. Currently, critical conditions, if reached, are not expected to persist long enough to warrant a Red Flag Warning, but will continue to monitor.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 PM HST Friday for Niihau, Kauai Leeward, Waianae Coast, Kahoolawe, Maui Leeward West, Kona, Kauai South, East Honolulu, Honolulu Metro, Ewa Plain, Molokai Southeast, Molokai Leeward South, Lanai Leeward, Lanai South, Maui Central Valley South, Kipahulu, South Maui/Upcountry, South Haleakala, Big Island South, Big Island Southeast.
Wind Advisory until 6 PM HST Friday for Lanai Mauka, Kahoolawe, Kohala, Lanai Windward, Lanai Leeward, Maui Central Valley North, Maui Central Valley South, Big Island South, Big Island Southeast, Big Island North.
Small Craft Advisory until 6 AM HST Friday for Kaiwi Channel, Maui County Windward Waters, Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Windward Waters, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov