West Side

Today: Mostly sunny with isolated showers. Highs 81 to 86. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 68 to 76. East winds up to 15 mph.

Sunday: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 80 to 86. Light winds becoming southwest around 10 mph in the afternoon. Chance of rain 30 percent.

South Side

Today: Mostly sunny. Highs around 89. North winds up to 15 mph increasing to 10 to 15 mph in the afternoon.

Tonight: Mostly clear. Lows 70 to 77. North winds up to 15 mph.

Sunday: Mostly sunny. Isolated showers in the afternoon. Highs around 88. North winds up to 10 mph shifting to the southwest around 10 mph in the afternoon. Chance of rain 20 percent.

North Shore

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 87 near the shore to around 68 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Tonight: Partly cloudy with isolated showers. Lows around 73 near the shore to around 53 near 5000 feet. 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 88 near the shore to around 68 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Central Maui

Today: Mostly sunny. Breezy. Highs 82 to 89. Northeast winds up to 20 mph increasing to 10 to 20 mph in the afternoon.

Tonight: Mostly clear. Lows around 71. Northeast winds up to 15 mph.

Sunday: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 82 to 89. North winds up to 10 mph. Chance of rain 30 percent.

Upcountry

Today: Mostly sunny. Isolated showers in the afternoon. Highs around 66 at the visitor center to around 71 at the summit. Northeast winds up to 10 mph in the morning becoming light. Chance of rain 20 percent.

Tonight: Mostly clear. Lows around 51 at the visitor center to around 48 at the summit. Light winds.

Sunday: Mostly sunny. Isolated showers in the afternoon. Highs around 66 at the visitor center to around 68 at the summit. Light winds. Chance of rain 20 percent.

East Maui

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 87 near the shore to around 68 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Tonight: Partly cloudy with isolated showers. Lows around 73 near the shore to around 53 near 5000 feet. 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 88 near the shore to around 68 near 5000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Lanai City

Today: Mostly sunny. Isolated showers in the afternoon. Highs 75 to 82. Northeast winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 20 percent.

Tonight: Mostly clear. Lows around 67. Northeast winds up to 15 mph.

Sunday: Mostly sunny. Scattered showers in the afternoon. Highs 73 to 82. Light winds. Chance of rain 30 percent.

Kaunakakai

Today: Mostly sunny. Isolated showers in the morning. Highs 74 to 90. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Isolated showers in the evening. Lows 61 to 75. Northeast winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers. Highs 74 to 90. Light winds. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Trades are expected to ease this afternoon, leading to hot and humid conditions as humidity levels gradually increase into early next week. Moderate trades return by the middle of next week, as Henriette moves northward away from the islands.

Discussion

Latest satellite imagery depicts light shower activity developing to the north of the islands, responsible for some light precipitation passing over Kauai and moving southeastward into Oahu this morning, however, resulting in little to no accumulation.
An area of high pressure remains well northeast of the islands, aiding in maintaining trades through much of the morning. Trades are then expected to ease beginning late today as Henriette, currently located east of the islands, is progged to pass north of the islands by early Monday, disrupting the local pressure gradient. In the wake of trades, a land-sea breeze pattern is favored through at least Monday, especially with the veering of low-level winds from an easterly to more southeasterly direction. As a result, leeward and interior islands may experience enhanced shower activity producing hot and humid conditions, as dewpoint values are projected to reach near 70 in many areas.
This will very much be short-lived, however, as once Henriette propagates north of the islands early next week, moderate trades will reestablish presence across the islands by late Tuesday, with a more typical summer weather pattern through the remainder of the forecast period.

Aviation

Trades will be on the gradual decline throughout today as a tropical system passes north of the islands, deteriorating the local pressure gradient. Limited clouds and shower activity is expected to windward and mauka areas, producing possible MVFR conditions. VFR conditions prevail otherwise.

Marine

Moderate to locally fresh trade winds will gradually ease today as Tropical Depression Henriette approaches the eastern boarder of the far offshore waters on a northwest track. Winds will become light and variable tonight into Monday morning due to the weakening ridge from Henriette. Henriette will move far north of the state Monday, allowing a ridge of high pressure to build just north of state. Trades winds will build back briefly to the moderate to fresh range Tuesday into Wednesday. Global models indicate a trough approaching the area from the east, weakening the ridge and allowing winds to ease to the light to gentle range toward the second half of next week.
A moderate, long period south swell that arrived Thursday will peak today allowing surf heights to reach high end High Surf Advisory (HSA) criteria. A HSA remains in effect for all south- facing shores through Sunday night. This swell will gradually fade into next week.
Choppy east facing shores conditions should ease slightly today as trade winds ease. Tropical Depression Henriette is expected to reach Tropical Storm strength tonight as it passes far east of the state, sending a medium period east swell. This swell could briefly increase the east facing shores Sunday before subsiding Monday. Below average east shore surf is expected Tuesday into Wednesday next week.
Tiny surf along north facing shores will trend down today as a small, medium northwest swell fades. Another small northwest swell is expected to arrive Sunday night into Monday.
Peak afternoon high tides, combined with elevated water levels running about a half a foot higher than predicted and a large south swell, will lead to minor flooding along many south-facing shorelines and low lying coastal areas through Sunday afternoon.

Fire weather

Trades will ease late today, allowing for the development of a land-sea breeze pattern for much of the state. Dewpoint values are expected to gradually rise throughout early next week, with many areas nearing dewpoints of 70. Given this, while fire weather concerns are not expected at this time, remain vigilant when recreating outdoors or when operating equipment that could cause a spark.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 AM HST Monday for Niihau, Kauai Leeward, Waianae Coast, Kahoolawe, Maui Leeward West, Kona, Kohala, Kauai South, East Honolulu, Honolulu Metro, Ewa Plain, Molokai Southeast, Molokai Leeward South, Lanai Leeward, Lanai South, Maui Central Valley South, South Maui/Upcountry, South Haleakala, Big Island South, Big Island Southeast.

Data Courtesy of NOAA.gov