Photo Credit: Brendan Stephen

West Kaua’i

Today: Mostly sunny in the morning then becoming partly sunny. Highs around 87 near the shore to around 75 above 3000 feet. Light winds.

Tonight: Partly cloudy. Lows 67 to 72 near the shore to around 58 above 3000 feet. Light winds.

Saturday: Mostly sunny. Highs around 87 near the shore to around 75 above 3000 feet. Light winds.

South Kaua’i

Today: Mostly sunny in the morning then becoming partly sunny. Highs around 84. Northeast winds up to 10 mph.

Tonight: Partly cloudy. Lows 65 to 71. Northeast winds around 10 mph.

Saturday: Mostly sunny. Highs around 84. Light winds becoming east around 10 mph in the afternoon.

Kaua’i Mountains

Today: Mostly sunny in the morning then becoming partly sunny. Highs 74 to 81 in the valleys to around 65 above 4000 feet. Light winds.

Tonight: Partly cloudy. Lows 58 to 63 in the valleys to around 53 above 4000 feet. Light winds.

Saturday: Mostly sunny. Highs 74 to 81 in the valleys to around 65 above 4000 feet. Light winds becoming east around 10 mph in the afternoon.

North Kaua’i

Today: Mostly sunny. Highs 77 to 86. Northeast winds up to 10 mph.

Tonight: Partly cloudy. Lows 61 to 71. Southeast winds up to 10 mph in the evening becoming light.

Saturday: Mostly sunny. Highs 77 to 86. Light winds becoming northeast around 10 mph in the afternoon.

East Kaua’i

Today: Mostly sunny. Highs 77 to 85. Northeast winds up to 10 mph.

Tonight: Partly cloudy. Lows 59 to 72. Northeast winds up to 10 mph in the evening becoming light.

Saturday: Mostly sunny. Highs 77 to 85. Light winds becoming east around 10 mph in the afternoon.

Detailed Forecast

Synopsis

Light winds will continue today with ridge just north of Kauai. Over the weekend the ridge is expected to lift northward, allowing trade winds to gradually return and strengthen. Moderate to locally breezy trade wind conditions are expected by Sunday, and persist into the middle of the new week. Very stable conditions will greatly limit shower activity through the weekend, with a slight increase in windward showers expected Monday and Tuesday. A more typical trade wind pattern should return by the middle of next week.

Discussion

As expected, no significant changes to the forecast or forecast philosophy with the morning package. The PoPs and associated fields were updated to reflect the latest guidance from the NBM from Monday night onwards. A relatively dry trade wind pattern is expected, through mid week, with a more typical trade wind pattern expected Thursday onwards.
An east to west oriented ridge remains north of Kauai, maintaining light winds across the state. As expected, clouds largely dissipated over the islands overnight with land breezes that formed in the light wind regime. Some cloud development is expected over the islands today with afternoon sea breezes. Chances of showers will remain very limited as the inversion heights remains below 5 kft, which will keep cloud development very shallow.
The ridge will begin to lift northward over the weekend, which will allow the trades to gradually return from south to north. Moderate to locally breezy conditions are expected by Sunday and persist into the middle of next week. Clouds and showers will return to the more typical windward and mauka areas, however shower activity will remain limited across the entire state over the weekend due to very stable conditions from low inversion levels. The trade wind inversion will begin to lift early next week, which should bring a slight increase in trade wind showers Monday and Tuesday, but will still remain drier than normal for this time of year. A more typical trade wind pattern should return during the middle to latter half of the week with rising inversion heights.

Aviation

A weak pressure gradient across the region will maintain light winds across the state today. As a result, daytime sea breezes and nighttime land breezes are expected to develop. Then winds will gradually strengthen tomorrow as the ridge of high pressure lifts slightly northward. Shower activity is expected to remain limited through the period due to the presence of a relatively dry air mass. VFR conditions will generally prevail, with brief MVFR conditions possible through this evening.
AIRMET Sierra is in effect for tempo mountain obscuration for leeward sections of the Big Island. These conditions should improve later this morning as land breezes help to dispel the lower cloud cover.

Marine

A weak elongated ridge in the northern offshore waters will hold in place over the region. Expect wind speeds to remain below Small Craft Advisory (SCA) threshold through Saturday. High pressure looks to redevelop north of the state over the weekend allowing moderate trade winds to build back. Models show the potential for SCA conditions across typical windier waters around Maui County and the Big Island by Sunday.
The current south-southwest swell will peak today and steadily decline through the weekend. Another, yet bigger moderate long period south- southwest swell will build through Saturday, peak Sunday night into Monday and could reach High Surf Advisory level criteria of 10 feet at the peak of the event. A moderate long period south swell is expected to reach HSA levels late next week too.
The current small northwest swell continues to decline. However, a reinforcing pulse from the northwest will build in late this afternoon to give north facing shores a small bump. Wind waves for east facing shores have diminished significantly and will remain small into the weekend.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov