West Side

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs around 79. East winds up to 10 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Lows 65 to 72. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs 77 to 82. Southwest winds up to 10 mph. Chance of rain 30 percent.

South Side

Today: Mostly sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 84. North winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Lows 63 to 74. Light winds.

Wednesday: Mostly sunny. Isolated showers in the afternoon. Highs around 84. Southwest winds around 10 mph. Chance of rain 20 percent.

North Shore

Today: Partly sunny with scattered showers. Highs around 80 near the shore to around 64 near 5000 feet. East winds up to 10 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 68 near the shore to around 50 near 5000 feet. Light winds. Chance of rain 30 percent.

Wednesday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 82 near the shore to around 65 near 5000 feet. Light winds. Chance of rain 30 percent.

Central Maui

Today: Mostly sunny in the morning then becoming partly sunny. Isolated showers. Highs 79 to 85. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Lows 63 to 68. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs 81 to 86. Southwest winds up to 10 mph. Chance of rain 30 percent.

Upcountry

Today: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 59 at the visitor center to around 66 at the summit. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with isolated showers. Lows 41 to 53. Light winds becoming south up to 10 mph after midnight. Chance of rain 20 percent.

Wednesday: Mostly sunny with isolated showers. Highs around 60 at the visitor center to around 66 at the summit. Southwest winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 20 percent.

East Maui

Today: Partly sunny with scattered showers. Highs around 80 near the shore to around 64 near 5000 feet. East winds up to 10 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 68 near the shore to around 50 near 5000 feet. Light winds. Chance of rain 30 percent.

Wednesday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 82 near the shore to around 65 near 5000 feet. Light winds. Chance of rain 30 percent.

Lanai City

Today: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 71 to 78. Light winds. Chance of rain 50 percent.

Tonight: Mostly cloudy with isolated showers. Lows around 64. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny with isolated showers. Highs 70 to 77. Light winds becoming southwest around 10 mph in the afternoon. Chance of rain 20 percent.

Kaunakakai

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 69 to 85. East winds up to 10 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with isolated showers. Lows 56 to 71. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny. Scattered showers in the afternoon. Highs 68 to 85. Southwest winds 10 to 15 mph. Chance of rain 30 percent.

Detailed Forecast

Synopsis

Light winds are expected today as a front draws closer and our surface pressure gradient weakens. This front is still forecast to reach Niihau and Kauai Wed night, then stall near Maui Thursday night. Brief moderate rain may accompany this first front. Another front will approach this weekend, and heavy rain is possible. Details will become clearer later in the week.

Discussion

Little has changed since the previous forecast as the models have shown good run-to-run consistency concerning the timing and placement of the Wed/Thu front. It should move through Niihau and Kauai Wed night, continue on to near Maui Thu night, then retreat northwest as it dissipates Friday. A second front will move over the western end of the state Sunday into Sunday night, with much more uncertainty in how far southeast it will be able to progress. At this time, we have increased the chance of rain Sunday through Monday, but have not added in a chance of thunder. We may end up doing that at some point, but it's too early now to specify exact locations.
In between these fronts, winds will be fairly light, allowing for additional days of sea- and land-breezes. This will favor clouds in leeward and mauka areas. Immediately behind these fronts, surface winds will likely come out of the north at light to moderate speeds.

Aviation

Most sites will see VFR today into tonight, with relatively light winds. Isolated showers will be driven largely by sea-breezes today and land-breezes tonight. Southerly winds are possible at HNL from late morning into the afternoon.
No airmets are in effect, and none are expected today. Turbulence aloft is expected to increase Wed several hundred miles to our NW and N.

Marine

A ridge of high pressure north of Hawaii will erode from the west as a front approaches the state from the northwest. Gentle to moderate easterly winds will weaken to light to gentle speeds and veer south to southeast today then southwest by Wednesday as the front approaches. The front will move west to east across the state late Wednesday into Thursday, with moderate northerly winds briefly filling in behind the front before it dissipates over Maui County Thursday night. Light southerly winds will redevelop Friday into Saturday as another front approaches the state from the northwest.
The first of two long to medium period overlapping northwest (310-320 degree) swells will continue to fill in this morning, building surf heights along north and west facing shores to near average. Forerunners of the second, slightly bigger swell will arrive tonight and peak Wednesday. Surf heights along north and west facing shores could reach marginal High Surf Advisory (HSA) levels Wednesday and hold into Thursday before slowly subsiding into the weekend. A moderate, long period northwest swell (320 degree) may gradually fill in over the weekend keeping surf from going flat.
Small, choppy east shore surf will become minimal over the next few days as trades near and upstream become disrupted by approaching fronts. Expect minimal background surf for south facing shores, with only a minor south- southwest pulse expected Wednesday afternoon into Thursday, keeping south shore surf heights just above flat levels.

Fire weather

Conditions should remain below critical fire thresholds through the week as winds remain light and RH elevated. Temperature inversion heights over Maui and the Big Island will range from 6,500 to 7,500 feet through today.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov