Photo Credit: Jason Weingardt

West Kaua’i

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

Tonight: Partly cloudy. Lows 68 to 73 near the shore to around 59 above 3000 feet. Light winds.

Sunday: Mostly sunny. Highs around 87 near the shore to around 75 above 3000 feet. Northeast winds up to 10 mph.

South Kaua’i

Today: Mostly sunny. Highs around 84. Northeast winds up to 15 mph.

Tonight: Partly cloudy. Lows 66 to 72. Northeast winds 10 to 15 mph.

Sunday: Mostly sunny. Highs around 84. Northeast winds 10 to 15 mph.

Kaua’i Mountains

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

Tonight: Partly cloudy. Isolated showers after midnight. Lows 59 to 64 in the valleys to around 54 above 4000 feet. East winds up to 10 mph in the evening becoming light. Chance of rain 20 percent.

Sunday: Mostly sunny. Isolated showers in the morning. Highs 74 to 81 in the valleys to around 65 above 4000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

North Kaua’i

Today: Mostly sunny. Highs 77 to 86. Northeast winds up to 15 mph.

Tonight: Partly cloudy. Lows 62 to 72. Southeast winds up to 10 mph.

Sunday: Mostly sunny. Highs 77 to 86. East winds around 10 mph becoming up to 15 mph in the afternoon.

East Kaua’i

Today: Mostly sunny. Highs 77 to 85. Northeast winds up to 10 mph increasing to 10 to 15 mph in the afternoon.

Tonight: Partly cloudy in the evening, then mostly cloudy with isolated showers after midnight. Lows 60 to 73. Northeast winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny. Isolated showers in the morning. Highs 77 to 85. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Light to gentle easterly trade winds are expected today, with a ridge north of the state. As the ridge lifts north tonight and Sunday, moderate to locally breezy easterly trade wind will build in. 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 anticipated, no significant updates to the forecast this morning.
A ridge remains just north of Kauai, bringing a hybrid sea breeze and gentle easterly trade wind flow across the state. Land breezes overnight have cleared the skies in most areas. Anticipate some clouds to develop later this morning and during the afternoon with some sea breezes setting up. Very little in the way of rainfall is expected.
The ridge will begin to lift northward and shift eastward this afternoon and evening, which will shift the winds to the northeast for a brief time. Expect moderate to locally breezy easterly trades to build back in Sunday, and then persist into the middle of the week as the ridge continues to shift northeast of the state. Clouds and showers will return to the more typical windward and mauka areas with the returning trades, however shower activity will remain limited due to very stable conditions from low inversion heights, and a dry airmass. 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

Light trade winds will strengthen slightly to become locally breezy by this afternoon and continue to gradually strengthen into Sunday. While land breezes have helped to clear out cloud cover overnight, sea breezes may have a harder time developing this afternoon with the uptick in trade winds…but expect some cloud build up over sheltered leeward areas. Shower activity will continue to remain limited. With the strong inversion in place, ceilings will be quite low with any clouds…which will allow for periods of MVFR conditions. Otherwise, VFR conditions will prevail.
No AIRMETs are currently in effect. However, AIRMET Sierra for tempo mountain obscuration may be needed at times as low clouds periodically impact mainly windward slopes with the exception of the leeward slopes and coast of the Big Island.

Marine

A weak elongated ridge in the northern offshore waters will move northward as high pressure redevelops north of the state this weekend. Winds are expected to gradually restrengthen tonight allowing moderate to locally strong trade winds to build back across the waters. A Small Craft Advisory (SCA) is likely for the typical windier waters around Maui County and the Big Island starting tonight through at least the first part of next week. Moderate to locally strong trade winds look to dominate the forecast over the next week.
The current High Surf Advisory (HSA) for south facing shores has been extended through Monday afternoon. Although the current south- southwest swell has declined slightly from its peak and surf may come down just below HSA levels today, a bigger moderate long period south- southwest swell is expected to slowly fill in this afternoon as long period forerunners arrive, then peak Sunday night into Monday. In the long range, another moderate long period south swell may generate solid HSA level surf, but below High Surf Warning level criteria late next week.
A tiny pulse from the northwest will give a slight bump for north facing shores. Wind waves for east facing shores have diminished significantly and will remain small today before ramping back up as wind wave chop increases due to the trade winds.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 PM HST Monday for Niihau, Kauai Leeward, Waianae Coast, Kahoolawe, Maui Leeward West, Kona, Kauai South, East Honolulu, Honolulu Metro, Ewa Plain, Molokai West, Molokai Leeward South, Lanai Leeward, Lanai South, Maui Central Valley South, South Maui/Upcountry, South Haleakala, Big Island South, Big Island Southeast.

Data Courtesy of NOAA.gov