West Side

Today: Mostly sunny with isolated showers. Haze. Highs 79 to 84. West winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly clear. Haze. Lows 66 to 72. Light winds.

Saturday: Mostly sunny in the morning then becoming mostly cloudy. Haze. Highs 78 to 83. Light winds becoming northeast up to 10 mph in the afternoon.

South Side

Today: Mostly sunny with isolated showers. Haze. Highs around 85. Light winds becoming west up to 10 mph in the afternoon. Chance of rain 20 percent.

Tonight: Mostly clear. Haze. Lows 65 to 74. Light winds.

Saturday: Sunny in the morning then becoming partly sunny. Haze. Highs around 86. Light winds becoming north up to 10 mph in the afternoon.

North Shore

Today: Mostly sunny with isolated showers. Haze. Highs around 80 near the shore to around 64 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Haze. Lows 67 to 72 near the shore to around 50 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 20 percent.

Saturday: Mostly sunny in the morning then becoming partly sunny. Isolated showers. Haze. Highs around 80 near the shore to around 64 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Central Maui

Today: Mostly sunny with isolated showers. Haze. Highs 81 to 86. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly clear. Haze. Lows 65 to 70. Light winds.

Saturday: Sunny in the morning then becoming partly sunny. Haze. Highs 80 to 86. Northeast winds up to 10 mph.

Upcountry

Today: Partly sunny with isolated showers. Haze. Highs around 61 at the visitor center to around 68 at the summit. Southeast winds up to 10 mph in the morning becoming light. Chance of rain 20 percent.

Tonight: Partly cloudy. Haze. Lows around 45 at the visitor center to around 47 at the summit. Light winds becoming northwest up to 10 mph after midnight.

Saturday: Mostly sunny in the morning then becoming partly sunny. Haze. Highs around 61 at the visitor center to around 69 at the summit. North winds up to 10 mph.

East Maui

Today: Mostly sunny with isolated showers. Haze. Highs around 80 near the shore to around 64 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Haze. Lows 67 to 72 near the shore to around 50 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 20 percent.

Saturday: Mostly sunny in the morning then becoming partly sunny. Isolated showers. Haze. Highs around 80 near the shore to around 64 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Lanai City

Today: Mostly sunny with isolated showers. Haze. Highs 72 to 80. Light winds. Chance of rain 20 percent.

Tonight: Partly cloudy. Haze. Lows around 65. Light winds.

Saturday: Mostly sunny in the morning then becoming mostly cloudy. Haze. Highs 72 to 79. Light winds.

Kaunakakai

Today: Mostly sunny with isolated showers. Haze. Highs 70 to 87. Light winds. Chance of rain 20 percent.

Tonight: Partly cloudy. Haze. Lows 57 to 72. Light winds.

Saturday: Mostly sunny in the morning then becoming mostly cloudy. Haze. Highs 70 to 86. Light winds.

Detailed Forecast

Synopsis

Winds are expected to remain light out of the southeast through the next few days. Stable air will keep most areas dry. A strong cold front will likely move through Kauai Wednesday, and may reach as far as Oahu, bringing stronger northerly winds and an increase in precipitation. This front is expected to recede back to the west and north Thursday, ushering in a return to trades.

Discussion

A surface high pressure center is located around 1000 miles northeast of the islands this morning. A ridge of high pressure extends southwest of this center, passing over the state and bringing us light southeast winds. A ridge aloft continues to bring us stable conditions, with light precip amounts (generally less than 0.05 inches except in the favored higher terrain) reported yesterday. Little change will occur through the weekend. Sea-breezes during the day and land-breezes at night will continue much like the past couple of days.
As we head into next week, an initial cold front will stall well to the west Monday. However, a strong trough in the upper atmosphere will then drive a second cold front toward the state. Latest models still show a spread in possible solutions, but have become slightly more confident that this front will move through Niihau/Kauai Wednesday, and may reach as far as Oahu. This will bring stronger northerly winds and an significant increase in precipitation. Winds will then become northeast and then east as the front recedes to the west and north Thursday into Friday, ushering in the return of trades winds. Models will continue to narrow down the exact path of this front over the next few days.
Vog from the recent eruption of Kilauea continues to be noted across much of the area, and southeast flow will keep it in the forecast for the next few days. Surface winds will be slightly stronger today than yesterday, but still on the weak side. A gradual warming of daytime highs is forecast through Monday.

Aviation

Light generally southeast winds remain in place over the state today, allowing for daytime sea-breezes and cloud development over interior and leeward areas. However, stable conditions will continue to limit shower development. Interior clouds will begin to dissipate after sunset as land-breezes resume overnight. Light to moderate southeast background flow will continue today and Saturday, with daytime sea-breezes once again developing over the islands. VFR flight conditions are expected to prevail over most locations into the weekend.
There are no AIRMETs in effect, and none are anticipated at this time.

Marine

Weak surface high pressure located northeast of the state will hold light to moderate east to southeast breezes through today. A cold front associated with a large very strong low moving across the Central Pacific will approach the far western islands early next week. Gentle to moderate easterly winds will veer more southerly ahead of this slow moving front that will eventually stall just west of Kauai Tuesday. The front may pass across Niihau and Kauai during the middle of next week. If this does occur, expect moderate to locally fresh northerly winds in the wake of the front. A very large northwest swell will pass around the islands from Saturday through Monday. This will increase seas to Small Craft Advisory heights (10 feet or higher) early next week.
A quick hitting reinforcing northwest swell will arrive early this morning that will help maintain HSA level surf through 8AM. North and west-facing shore surf should drop Friday afternoon and evening.
The aforementioned low is located about 1,400 nm northwest of Kauai is generating a large fetch of seas. This fetch is being aimed straight down the northwest great circle route toward the islands. This very large northwest swell will produce XL size surf along north and west-facing small island shores Saturday night through Monday morning. Long period forerunners will begin arriving Saturday afternoon, then surf will quickly ramp up Saturday evening. The peak of this event is forecast to be from late Saturday night through Sunday morning. There is a high potential for giant size surf (40 to 50 feet) along the north- facing shores of the smaller islands Saturday night into Sunday. A High Surf Warning for these shores will likely be in effect from Saturday night into Monday.
East-facing chop will remain small through the weekend due to weak winds. Select south-facing shores will likely experience westerly wrap from this weekend's large northwest swell passage.

Fire weather

Even though we will see relative humidity levels fall heading into the weekend, weak winds will preclude reaching critical fire weather conditions for the next few days. Temperature inversion heights near Big Island and Maui will range between 5000 and 7000 feet.

HFO Watches/Warnings/Advisories

High Surf Advisory until 8 AM HST this morning for Niihau, Kauai Leeward, Waianae Coast, Oahu North Shore, Maui Windward West, Kauai North, Molokai Windward, Molokai North, Molokai West, Maui Central Valley North, Windward Haleakala.

Data Courtesy of NOAA.gov