West Side

Tonight: Mostly clear. Isolated showers in the evening. Lows 64 to 73. East winds up to 15 mph. Chance of rain 20 percent.

Tuesday: Sunny and breezy. Highs 74 to 86. Northeast winds up to 15 mph increasing to 10 to 20 mph in the afternoon.

Tuesday Night: Partly cloudy. Lows 64 to 72. Northeast winds up to 15 mph.

South Side

Tonight: Mostly clear. Lows 66 to 71. North winds up to 15 mph.

Tuesday: Mostly sunny. Breezy. Highs 77 to 87. North winds 10 to 20 mph.

Tuesday Night: Partly cloudy. Lows 66 to 71. North winds up to 15 mph.

North Shore

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows around 70 near the shore to around 53 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 50 percent.

Tuesday: Mostly sunny in the morning then becoming partly sunny. Isolated showers. Highs 78 to 83 near the shore to around 67 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Tuesday Night: Mostly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 70 near the shore to around 53 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 40 percent.

Central Maui

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

Tuesday: Mostly sunny. Breezy. Highs 81 to 88. Northeast winds 10 to 20 mph.

Tuesday Night: Partly cloudy. Lows 65 to 70. Northeast winds up to 15 mph.

Upcountry

Tonight: Partly cloudy. Isolated showers in the evening. Lows around 44 at the visitor center to around 41 at the summit. Light winds. Chance of rain 20 percent.

Tuesday: Mostly sunny in the morning then becoming partly sunny. Highs 51 to 68. Light winds becoming east up to 10 mph in the afternoon.

Tuesday Night: Mostly cloudy. Lows around 44 at the visitor center to around 41 at the summit. East winds up to 10 mph in the evening becoming light.

East Maui

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows around 70 near the shore to around 53 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 50 percent.

Tuesday: Mostly sunny in the morning then becoming partly sunny. Isolated showers. Highs 78 to 83 near the shore to around 67 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Tuesday Night: Mostly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 70 near the shore to around 53 near 5000 feet. Southeast winds up to 15 mph. Chance of rain 40 percent.

Lanai City

Tonight: Partly cloudy. Breezy. Isolated showers in the evening. Lows 59 to 66. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Tuesday: Mostly sunny. Breezy. Isolated showers in the afternoon. Highs 70 to 80. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Tuesday Night: Partly cloudy in the evening then becoming mostly cloudy. Breezy. Lows 59 to 66. Northeast winds 10 to 20 mph.

Kaunakakai

Tonight: Mostly clear. Isolated showers in the evening. Lows 56 to 72. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Tuesday: Sunny and breezy. Highs 68 to 87. Northeast winds 10 to 20 mph.

Tuesday Night: Partly cloudy. Lows 56 to 72. Northeast winds 10 to 15 mph.

Detailed Forecast

Synopsis

Gentle to moderate trade winds will prevail through Thursday as a weak surface ridge sits about 300 miles north of Kauai. Modest showers will remain focused over most windward slopes, though an upper-level disturbance may produce more rainfall on Kauai late Tuesday and Wednesday. The disturbance will also generate areas of high clouds over mainly the southern end of the island chain. Trades will strengthen and become more stable Friday and Saturday.

Discussion

Trade winds have eased as a weakened subtropical ridge has been displaced to about 300 miles north of Kauai. A weak upper-level trough is centered just north of Kauai, sending thin high clouds over the Big Island, and a mid-level ridge is maintaining stable conditions with an inversion based between 5000 and 6500 feet. Moisture within the trade wind flow is unimpressive and has resulted in low rainfall totals along windward slopes, mainly confined to portions of Big Island and Kauai where small pockets of showers moved through early in the morning. This afternoon, dry conditions dominate, with the exception of typical afternoon clouds and scattered showers over the South Kona slopes.
The subtropical ridge will remain roughly stationary through Thursday, keeping trades in the gentle to locally moderate range. A shallow low aloft will develop within the upper-level trough just north of Kauai on Tuesday. A narrow band of moisture will move onto the Garden Isle Tuesday night and Wednesday, and the modest instability provided by the low aloft will likely produce slightly active showers on windward slopes, while leeward Kauai could experience scattered afternoon showers. Across the rest of the state, shower activity should remain low and focused mainly over windward areas under continued stable conditions, while sheltered leeward terrain experiences clouds and maybe an isolated shower each afternoon. The low aloft will generate high clouds, mainly over Big Island and Maui.
Trade winds should strengthen a notch Friday and Saturday as surface high pressure rebuilds far northeast of the state. The low aloft will be pushed off to the east, and ridging aloft will move overhead and bring stable and somewhat dry conditions. Trade winds will become more easterly and may ease slightly Sunday due to a surface trough developing several hundred miles west of the islands.

Aviation

Regional satellite imagery this afternoon reveals very little upstream of the islands in the way of clouds and showers. Moderate east northeasterly trade winds will prevail throughout the next few days. VFR conditions are expected across much of the state through Tuesday, with only brief passing showers possible over windward locations throughout this period.
There are currently no AIRMETs in effect and none are anticipated through tonight.

Marine

High pressure to the far north-northwest will drift west and weaken over the next several days, with easterly trade winds gradually easing into the gentle to locally fresh range through the week.
Surf along south facing shores will remain small through Tuesday, with a tiny to small long-period reinforcement will expected late tonight. A long-period south-southwest swell is expected Wednesday into Thursday and will bring another boost to south shore surf.
East shore surf will gradually decline through mid-week as the trades weaken slightly. Surf along north facing shores will remain tiny for the next several days. Gale force winds associated with a surface low moving near the Aleutians this weekend are expected to send a small, medium-period north-northwest swell towards the islands for the latter half of the week.
Through Wednesday, higher than normal tides could lead to some coastal flooding during the peak of high tides in the early afternoon hours. However, since the elevated tides are generally expected between the peaks of the aforementioned south swells, this event should have minimal impacts.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov