West Side

Today: Partly sunny with scattered showers. Highs 72 to 77. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 64 to 70. Northeast winds up to 15 mph. Chance of rain 20 percent.

Friday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 76. East winds up to 10 mph. Chance of rain 30 percent.

South Side

Today: Mostly sunny with isolated showers. Highs around 78. North winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Lows 63 to 72. North winds around 10 mph.

Friday: Mostly sunny. Isolated showers in the afternoon. Highs around 80. Light winds. Chance of rain 20 percent.

North Shore

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 76 near the shore to around 61 near 5000 feet. North winds up to 10 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows around 67 near the shore to around 49 near 5000 feet. Light winds. Chance of rain 40 percent.

Friday: Partly sunny with scattered showers. Highs around 78 near the shore to around 61 near 5000 feet. Light winds becoming east up to 15 mph in the afternoon. Chance of rain 50 percent.

Central Maui

Today: Partly sunny with scattered showers. Highs around 77. Northeast winds up to 10 mph. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 63 to 68. Northeast winds around 10 mph in the evening becoming light. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs around 78. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 20 percent.

Upcountry

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs around 56 at the visitor center to around 58 at the summit. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows around 45 at the visitor center to around 38 at the summit. Southeast winds up to 10 mph. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs around 57 at the visitor center to around 59 at the summit. Southeast winds up to 10 mph. Chance of rain 20 percent.

East Maui

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 76 near the shore to around 61 near 5000 feet. North winds up to 10 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows around 67 near the shore to around 49 near 5000 feet. Light winds. Chance of rain 40 percent.

Friday: Partly sunny with scattered showers. Highs around 78 near the shore to around 61 near 5000 feet. Light winds becoming east up to 15 mph in the afternoon. Chance of rain 50 percent.

Lanai City

Today: Partly sunny with scattered showers. Highs 66 to 74. Northeast winds 10 to 15 mph. Chance of rain 30 percent.

Tonight: Partly cloudy with isolated showers. Lows around 63. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 68 to 76. Northeast winds up to 10 mph. Chance of rain 30 percent.

Kaunakakai

Today: Partly sunny with scattered showers. Highs 64 to 80. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 54 to 69. Northeast winds 10 to 15 mph decreasing to up to 10 mph after midnight. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs 64 to 81. Northeast winds up to 10 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

A stalled out front will persist over Maui County today, continuing to bring periods of shower activity, namely to Maui County and windward portions of the Big Island. Unsettled weather resumes this weekend as another slower-moving front meanders over the islands. Conditions improve, drying out the islands beginning early next week as a surface high builds north of the islands.

Discussion

A stalled out front bisects the Hawaiian Islands along Maui County, persisting through much of the day and will continue to bring periods of shower activity to predominately Maui County and windward portions of the Big Island. Latest model guidance depicts upper-level troughing with a series of complex lows will maintain these lingering showers along the moisture axis associated with the aforementioned stalled out front over the next several days, namely across windward and mauka locations as northeastern flow prevails. Previous shift mentioned the potential for flood- related products given the development of higher rain rates, which may result in minor flooding and ponding of water on roadways. This will need to be monitored through the remainder of the week going forward.
As the weekend approaches, model guidance of the GFS and ECMWF supports a relatively active weather pattern with periods of shower activity for the islands. Northeastern flow will begin to veer southeasterly during this time in response to the next, slower-moving frontal boundary approaching the islands from the northwest associated with a deep low well north of the islands meandering toward the Gulf of Alaska. Model total precipitable water (PWATs) connected with this next frontal boundary are on the range of 2 to 3 standard deviations higher than average. Increasing instability aloft combined with deep moisture pooling northward across the islands associated with the aforementioned system will sustain a wet pattern through the weekend.
By early next week, conditions will begin to improve as the frontal boundary exits to the east and a drier airmass fills the void as a surface high builds just north of the islands with extensive ridging aloft.

Aviation

A weak stalled out front over the eastern end of the state will continue to produce some showers mainly over windward and mauka areas today and tonight. Drier conditions are expected over the western islands of Kauai and Oahu. Some MVFR cigs/vsbys may affect windward portions of Molokai, Maui and the Big Island at times, but predominantly VFR conditions are expected statewide during the next 24 hours.
AIRMET Tango remains in effect for moderate upper level turbulence across Oahu and Maui County. Conditions should improve later this morning.
AIRMET Zulu is in effect for moderate icing in the layer from 120-FL240. This AIRMET could remain in place for much of the day.

Marine

Light to moderate northeast winds will persist into Friday across most waters as a stalled frontal boundary gradually diminishes over the eastern end of the state and high pressure builds to the north. The exception will be over the Big Island waters east of the boundary, where light east to southeast winds will prevail. Guidance indicates a progressive pattern continuing into the weekend, with a front approaching and moving through the area Sunday into Monday, followed by another front approaching by midweek. The weekend front could bring locally heavy showers to portions of the marine area, along with a period of moderate to locally fresh southwest winds.
Surf along exposed north- and west-facing shores will remain near advisory levels into Friday as overlapping west-northwest and north-northwest swells move through. Overnight offshore buoy observations reflect this mixed swell regime, with north-northwest energy in the 1012 second range and west-northwest energy holding in the 1315 second bands. Guidance shows these swells easing late Friday into the weekend, with a small, long-period northwest swell arriving late Saturday.
Surf along east-facing shores will remain small into next week due to the lack of persistent trade winds locally and upstream.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov