Photo Credit: Brendan Stephen

West Kaua’i

Today: Partly sunny. Showers likely in the morning, then scattered showers in the afternoon. Highs around 84 near the shore to around 72 above 3000 feet. Southeast winds up to 10 mph. Chance of rain 60 percent.

Tonight: Partly cloudy with isolated showers. Lows around 69 near the shore to around 58 above 3000 feet. Light winds becoming east around 10 mph after midnight. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers. Highs around 84 near the shore to around 72 above 3000 feet. East winds around 10 mph. Chance of rain 20 percent.

South Kaua’i

Today: Partly sunny. Showers likely in the morning, then scattered showers in the afternoon. Highs around 81. Southeast winds up to 10 mph. Chance of rain 60 percent.

Tonight: Mostly cloudy with scattered showers. Lows 65 to 70. East winds around 10 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs around 81. East winds 10 to 15 mph. Chance of rain 50 percent.

Kaua’i Mountains

Today: Mostly cloudy with numerous showers. Highs 71 to 78 in the valleys to around 62 above 4000 feet. Light winds. Chance of rain 70 percent.

Tonight: Mostly cloudy with scattered showers. Lows 58 to 63 in the valleys to around 51 above 4000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs 71 to 78 in the valleys to around 62 above 4000 feet. East winds 10 to 15 mph. Chance of rain 50 percent.

North Kaua’i

Today: Partly sunny with scattered showers. Highs 74 to 84. Light winds. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers. Lows 61 to 69. East winds around 10 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs 74 to 84. East winds 10 to 15 mph. Chance of rain 50 percent.

East Kaua’i

Today: Partly sunny. Showers likely in the morning, then scattered showers in the afternoon. Highs 74 to 83. South winds up to 10 mph. Chance of rain 60 percent.

Tonight: Mostly cloudy with scattered showers. Lows 58 to 71. East winds around 10 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs 74 to 83. East winds 10 to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Trade winds will begin to fill in across the eastern half of the state today and expand westward on Sunday. Drier conditions will return to most of the state, but showers will linger near Kauai through today and select interior and leeward areas could see scattered showers this afternoon. A breezy trade wind pattern will return across the state during the first half of next week.

Discussion

An upper low northeast of the Big Island this morning will continue to move eastward through the forecast period and fill in, allowing weak upper ridging to develop across the islands. Yesterday's associated heavy rainfall and deep convection across the Big Island has collapsed, with satellite loop now showing scattered low clouds to clear skies from Oahu eastward. An area of showery low clouds continues to linger across and around Kauai. This will diminish and get pushed westward away from the islands as trade winds fill in tonight and Sunday.
Expect less shower activity today versus yesterday, with mainly fair weather conditions for most of the islands. The one exception could be over Kauai, where southerly winds in the low levels will continue to bring showers to the area through today. Easterly trades will begin to return today, but winds may still be light enough for localized sea breezes to develop across protected areas. Afternoon showers are possible and, due to the background easterly flow, showers will likely develop over interior areas and drift westward this afternoon. With the stabilizing atmosphere, shower intensity should remain light to moderate.
Trades will further strengthen Sunday into Monday, with a typical breezy trade wind weather pattern returning during the first half of next week. An increase in low level moisture is possible Monday into Tuesday, which could bring periods of increased showery weather for windward areas.

Aviation

Early this morning, an area of showers and low clouds continues to linger near and just west of Kauai, producing occasional MVFR ceilings and steady rainfall near Niihau. Much drier conditions have overspread the remaining islands throughout the night as an upper low moves off to the east and weak upper ridging develops across the state.
Southerly low level winds will continue to support showers near Kauai today. Easterly trade winds begin to build back into the region across the eastern half of the state today before expanding westward on Sunday. With that said, trades may still be light enough for localized sea breezes to develop this afternoon, which could produce some light to moderate interior and leeward showers. Regardless, VFR conditions are expected to prevail at most locations throughout the forecast period.
AIRMET Sierra for mountain obscuration remains in effect for Kauai early this morning. This AIRMET will likely remain in effect through the rest of the morning, but showers and low clouds should diminish later today.

Marine

High pressure will build to the northeast, leading to strengthening trade winds that will produce Small Craft Advisory (SCA) conditions around the Big Island and Maui County beginning tonight. Trades will increase to fresh to locally strong levels Sunday and Monday and then drop slightly on Wednesday.
Surf will be below seasonal average through much of the week. Inconsistent pulses of south-southwest and south-southeast swell will produce surf just below seasonal average though the weekend, followed by mainly summertime background sized surf next week. A small, short-period north swell will fade tonight, with a tiny pulse of northwest swell possible late Sunday and Monday. As trade winds return, expect rough east shore to build Sunday and Monday but remain below seasonal average through the week.

HFO Watches/Warnings/Advisories

Small Craft Advisory from 6 PM this evening to 6 PM HST Sunday for Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov