Photo Credit: Brendan Stephen

West Kaua’i

Today: Mostly sunny. Scattered showers in the afternoon. Highs around 88 near the shore to around 76 above 3000 feet. West winds up to 10 mph. Chance of rain 30 percent.

Tonight: Partly cloudy. Scattered showers early in the evening. Lows 64 to 69 near the shore to around 55 above 3000 feet. Light winds. Chance of rain 30 percent.

Wednesday: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs around 88 near the shore to around 76 above 3000 feet. Southwest winds up to 10 mph. Chance of rain 30 percent.

South Kaua’i

Today: Mostly sunny. Isolated showers in the afternoon. Highs around 85. Northwest winds up to 10 mph shifting to the southwest in the afternoon. Chance of rain 20 percent.

Tonight: Partly cloudy. Isolated showers early in the evening. Lows 62 to 68. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 85. Southeast winds up to 10 mph shifting to the south in the afternoon. Chance of rain 20 percent.

Kaua’i Mountains

Today: Partly sunny. Scattered showers in the afternoon. Highs 75 to 82 in the valleys to around 66 above 4000 feet. Light winds. Chance of rain 30 percent.

Tonight: Mostly cloudy early in the evening then becoming partly cloudy. Scattered showers early in the evening. Lows 55 to 60 in the valleys to around 50 above 4000 feet. Light winds. Chance of rain 30 percent.

Wednesday: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 75 to 82 in the valleys to around 66 above 4000 feet. Light winds. Chance of rain 30 percent.

North Kaua’i

Today: Mostly sunny. Scattered showers in the afternoon. Highs 78 to 87. Southwest winds up to 10 mph shifting to the northwest in the afternoon. Chance of rain 30 percent.

Tonight: Partly cloudy. Scattered showers early in the evening. Lows 58 to 68. Light winds. Chance of rain 30 percent.

Wednesday: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 78 to 87. Northwest winds up to 10 mph. Chance of rain 30 percent.

East Kaua’i

Today: Partly sunny. Isolated showers in the afternoon. Highs 78 to 86. Southwest winds up to 10 mph shifting to the east in the afternoon. Chance of rain 20 percent.

Tonight: Mostly cloudy early in the evening then becoming partly cloudy. Isolated showers early in the evening. Lows 56 to 70. Light winds. Chance of rain 20 percent.

Wednesday: Mostly sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs 78 to 86. South winds up to 10 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

A land and sea breeze pattern is expected today through Thursday, with sea breezes allowing for the development of a few daytime heating driven showers each afternoon, while land breezes keep most showers offshore or very near the coast each night. Moderate trade winds and a more typical windward and mauka focused shower pattern should return by Friday, with this pattern then holding through early next week.

Discussion

Currently at the surface, a 1028 mb high is positioned around 1800 miles northeast of Honolulu, while a cold front is located around 550 miles northwest of Kauai. The gradient has continued to weaken overnight, with land breezes present across much of the state. Infrared satellite imagery shows mostly cloudy conditions over Oahu and the Big Island, with partly cloudy skies elsewhere. Radar imagery shows some showers moving into windward areas from Oahu eastward to the Big Island, with even a few showers hugging the coasts in leeward locales. Main short term focus revolves around trade wind trends and rain chances.
A land and sea breeze pattern is expected statewide today through early Thursday as an approaching front keeps the gradient weak across the island chain. The front is forecast to stall out just northwest of Kauai Wednesday night, then weaken into a trough and shift westward through the remainder of the work week while ridging rebuilds to the northwest of the islands. This should allow the trade winds to slowly return from east to west across the state Thursday and Thursday night, with moderate trades then holding in place Friday through early next week.
As for the remaining weather details, land and sea breezes will be dominant today through early Thursday, with showers developing over interior and mauka areas each afternoon, then holding mainly offshore or very near the coast each night. Although the trades will begin to return Thursday, the combination of daytime heating and localized sea breezes will likely allow for some leeward and interior shower development in the afternoon once again. More typical trade wind weather featuring mainly windward and mauka showers should return by Friday and prevail through early next week.

Aviation

Light winds will allow for localized land and sea breezes to drive the weather pattern through mid week, with clouds and showers developing over inland locations during the day and then gradually dissipating overnight and pushing offshore. VFR conditions will generally prevail, except for in any heavier showers that will bring periodic MVFR ceilings and visibilities.
There are currently no AIRMETs in effect.

Marine

Light winds will hold over the waters during the next few days as a cold front approaches from the northwest and stalls just northwest of Kauai. This front will weaken into a trough and shift westward Thursday allowing the trade winds to gradually restrengthen and reach moderate to locally strong speeds Friday through the weekend.
The current small north-northwest swell will gradually lower today, while a new longer period northwest swell begins to arrive. This new swell is expected to build tonight and peak at moderate levels on Wednesday bringing another round of elevated surf to north and west facing shores. This swell will then shift to a more northerly direction while holding at moderate levels Thursday through Friday, before subsiding over the weekend.
East shore surf will trend downward today and tonight, then hold at very small levels Wednesday through Friday. A slight boost is possible over the weekend as the trades strengthen. A lingering small south-southeast swell will keep south shore surf up slightly through Wednesday, before lowering Thursday and Friday. A new long period south swell will arrive for the weekend, giving south shore surf a nice late season boost.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov