West Side

Tonight: Mostly cloudy. Lows 65 to 72. East winds 10 to 15 mph.

Saturday: Mostly sunny. Breezy. Highs 73 to 85. Northeast winds 10 to 20 mph.

Saturday Night: Mostly clear. Breezy. Isolated showers in the evening. Lows 64 to 72. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

South Side

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

Saturday: Sunny and breezy. Highs 76 to 87. Northeast winds up to 20 mph.

Saturday Night: Clear and breezy. Lows 65 to 70. Northeast winds up to 20 mph.

North Shore

Tonight: Mostly cloudy. Isolated showers after midnight. Lows around 69 near the shore to around 53 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Saturday: Mostly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 78 to 83 near the shore to around 67 near 5000 feet. East winds up to 20 mph. Chance of rain 30 percent.

Saturday Night: Breezy. Mostly cloudy with scattered showers. Lows around 69 near the shore to around 53 near 5000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Central Maui

Tonight: Mostly cloudy. Lows around 67. East winds 10 to 15 mph.

Saturday: Sunny and breezy. Highs 80 to 87. Northeast winds 10 to 20 mph.

Saturday Night: Mostly clear. Breezy. Lows 64 to 69. East winds 10 to 20 mph.

Upcountry

Tonight: Mostly cloudy. Breezy. Lows 41 to 52. East winds up to 20 mph.

Saturday: Sunny and breezy. Highs 52 to 70. East winds up to 20 mph.

Saturday Night: Breezy. Mostly clear with scattered showers. Lows around 44 at the visitor center to around 42 at the summit. East winds up to 20 mph increasing to 10 to 25 mph after midnight. Chance of rain 50 percent.

East Maui

Tonight: Mostly cloudy. Isolated showers after midnight. Lows around 69 near the shore to around 53 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Saturday: Mostly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 78 to 83 near the shore to around 67 near 5000 feet. East winds up to 20 mph. Chance of rain 30 percent.

Saturday Night: Breezy. Mostly cloudy with scattered showers. Lows around 69 near the shore to around 53 near 5000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Lanai City

Tonight: Mostly cloudy. Breezy. Lows 58 to 66. Northeast winds 10 to 20 mph.

Saturday: Mostly sunny. Breezy. Highs 70 to 80. Northeast winds 10 to 25 mph.

Saturday Night: Mostly clear. Breezy. Lows 59 to 66. Northeast winds 10 to 25 mph.

Kaunakakai

Tonight: Mostly cloudy. Lows 55 to 72. East winds 10 to 15 mph.

Saturday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 68 to 86. East winds 10 to 20 mph. Chance of rain 20 percent.

Saturday Night: Partly cloudy. Breezy. Lows 55 to 72. East winds 10 to 25 mph.

Detailed Forecast

Synopsis

A series of high pressure systems building to the northwest and north of the state will keep moderate to breezy trades in place through late next week. A front in the vicinity of Kauai will keep windward areas showery tonight and Saturday, with drier conditions across the remainder of the state. The front will weaken into a trough and shift west Saturday night and Sunday, bringing a drier and more uniform trade wind shower pattern to the entire state. The old frontal remnants will shift back southward into the area early next week, then meander across the islands through late next week. This will bring a more typical or slightly wetter than normal trade wind pattern to the state Monday through next Friday.

Discussion

Currently at the surface, a front is nearly stationary in the vicinity of Kauai, while a 1032 mb high is centered around 1200 miles northwest of Honolulu. The resulting gradient is producing moderate to locally breezy trades across the state this evening. Infrared satellite imagery shows a combination of high and low clouds resulting in mostly cloudy conditions. Radar imagery shows scattered showers moving into windward sections of Kauai, with isolated showers affecting windward sections Oahu, Maui County, and the Big Island. Main short term focus revolves around rain chances and trade wind trends.
A series of strong high pressure systems will remain to the northwest and north of the islands during the next 7 days, keeping moderate to breezy trade winds in place with only minor fluctuations in strength from day to day.
The front will gradually weaken in the vicinity of Kauai tonight and Saturday, keeping windward sections of the Garden Isle rather showery. Elsewhere, drier conditions will prevail, with mostly isolated to scattered showers for windward sections of the other islands. The front will weaken into a trough and shift northwest of Kauai Saturday night and Sunday, bringing a more uniform trade wind shower pattern back to the islands. The old front remnants will push southward into the area again early next week, then hold over the state through late next week. This will bring a more typical or slightly wetter than normal trade wind pattern to the islands. Showers will favor windward slopes and coasts, with some of the showers reaching leeward areas at times due to the strength of the trades.
The high clouds will steadily exit from northwest to southeast down the island chain tonight through Saturday. The particularly thick Vog that was in place today, will fade out over the smaller islands through the weekend as the returning trades help to disperse and shift it off to the southwest.

Aviation

A dissipating front near Kauai will remain nearly stationary tonight keeping MVFR conditions with brief IFR possible due to low clouds and showers over the island lasting into Saturday. Over Oahu brief periods of MVFR conditions in passing showers are possible, mainly over windward and mountain areas. Elsewhere, trade winds building back into the state will bring more typical trade wind weather with low clouds and showers favoring windward and mountain areas in the overnight to early morning hours.
An area of Volcanic smOG (VOG), moving through the islands as a dense haze, may also reduce local visibilities at times. Vog concentrations will decrease across the region this weekend as trade winds return.
AIRMET Sierra remains in effect for mountain obscuration for all of Kauai and north through east sections of Oahu likely lasting into the morning hours.
AIRMET Tango remains in effect for tempo moderate upper level turbulence likely lasting into the morning hours.

Marine

Rough marine conditions are expected over the weekend due to a combination of fresh to strong trade winds and building seas. Small Craft Advisory conditions will likely develop across most Hawaiian waters and may persist into Monday before gradually improving. Trade winds are forecast to ease slightly on Monday and Tuesday as the surface high weakens, then rebuild by Wednesday. Seas should also dip below advisory levels early next week as both the winds relax and the large weekend swell subsides.
Surf along north-facing shores will remain rough overnight, driven by a combination of short- to medium-period north-northwest (330-340 degrees) swell and northeast trade wind seas. A significant upward trend is expected Saturday as a large, long- period north-northwest swell (340-360 degrees) arrives. This swell will push surf to warning levels along north and exposed east-facing shores, with advisory-level surf likely for exposed west-facing shores Saturday through Sunday. Moderate to strong harbor surges are anticipated in north-facing harbors through the weekend. A gradual decrease in surf is expected through the first half of next week as the swell eases.
Small surf will persist along south-facing shores through early Sunday. A series of small south swells may bring slight increases in surf late Sunday into Monday and again around midweek.

HFO Watches/Warnings/Advisories

High Surf Warning until 6 PM HST Sunday for Niihau, Oahu North Shore, Olomana, Maui Windward West, Kauai North, Kauai East, Koolau Windward, Molokai Windward, Molokai North, Maui Central Valley North, Windward Haleakala, Big Island East, Big Island North.
High Surf Advisory from 6 AM Saturday to 6 PM HST Sunday for Kauai Leeward, Waianae Coast, Maui Leeward West, Molokai West.
Small Craft Advisory until 6 PM HST Sunday for Kauai Northwest Waters, Kauai Windward Waters, Kauai Leeward Waters, Kauai Channel, Oahu Windward Waters, Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.
Small Craft Advisory from 6 AM Saturday to 6 PM HST Sunday for Oahu Leeward Waters, Kaiwi Channel, Maui County Windward Waters, Big Island Windward Waters.

Data Courtesy of NOAA.gov