Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly cloudy. Isolated showers 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 15 mph. Chance of rain 30 percent.

Tonight: Mostly cloudy with isolated showers. Lows 71 to 76 near the shore to around 62 above 3000 feet. East winds up to 10 mph. Chance of rain 20 percent.

Sunday: Mostly cloudy. Isolated showers 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 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 50 percent.

South Kaua’i

Today: Mostly cloudy with isolated showers. Highs around 81. South winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy with isolated showers. Lows 69 to 75. Light winds. Chance of rain 20 percent.

Sunday: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 81. South winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 40 percent.

Kaua’i Mountains

Today: Mostly cloudy. Isolated showers in the afternoon. Highs 71 to 78 in the valleys to around 62 above 4000 feet. South winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Lows 62 to 68 in the valleys to around 56 above 4000 feet. South winds up to 10 mph. Chance of rain 20 percent.

Sunday: Cloudy. Scattered showers in the afternoon. Highs 71 to 78 in the valleys to around 62 above 4000 feet. South winds up to 10 mph. Chance of rain 50 percent.

North Kaua’i

Today: Mostly cloudy with isolated showers. Highs 74 to 84. South winds up to 10 mph shifting to the northwest in the afternoon. Chance of rain 20 percent.

Tonight: Mostly cloudy with isolated showers. Lows 66 to 75. South winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly cloudy with isolated showers. Highs 74 to 84. South winds up to 15 mph. Chance of rain 20 percent.

East Kaua’i

Today: Mostly cloudy. Isolated showers in the afternoon. Highs 74 to 83. Southwest winds up to 15 mph shifting to the south in the afternoon. Chance of rain 20 percent.

Tonight: Mostly cloudy with isolated showers. Lows 63 to 76. Southwest winds up to 10 mph. Chance of rain 20 percent.

Sunday: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 74 to 83. South winds 10 to 15 mph. Chance of rain 40 percent.

Detailed Forecast

Synopsis

Light southerly winds with mostly dry conditions will persist through the weekend. High clouds associated with a lingering frontal boundary nearby to the north along with an approaching upper disturbance may lead to periods of cloudy conditions, especially over the western end of the state. Rain chances may increase through the first half of next week as deep low pressure develops to the west.

Discussion

The persistent pattern featuring a stationary frontal boundary lingering nearby to the north and a ridge meandering over the islands will keep the light southerly flow in place through the weekend. With the deep moisture axis north of the area over and around the frontal boundary, expect showers to remain limited this weekend. Any showers that do form will favor interior/south and southwest facing slopes through the afternoons where sea breezes form – best chance for accumulations being over the western end of the state closer to the deep moisture axis and better instability.
An upper low will cutoff west of the state Sunday and induce a surface low to the west. This will lift the front northward while high pressure builds far northeast of the area. Southeast flow will strengthen early next week in response and begin to push moisture over the islands that will continue for much of next week. There are some model differences in response to various positions in where the low pressure sets up to the west, with the GFS placing the feature closer to the islands and bringing more rainfall across the state and the ECMWF keeping most of the activity farther west. A blend of the available sources of guidance does support a hybrid-like pattern with east-southeast flow along with increasing moisture expanding eastward across the state Monday through midweek. Guidance shows this feature to the west lifting northeastward and phasing with the northern stream late in the week, which could allow for the local pattern to transition back toward a typical trade wind setup by the end of next weekend.

Aviation

Mostly clear skies and scant showers will prevail today and tonight. A front passing north of the main Hawaiian islands will spread scattered high clouds over the islands from time to time. Light to moderate southerly to southeasterly flow will prevail through the forecast period. Expect isolated showers near Kauai through this morning. VFR conditions are expected statewide, and no AIRMETs are expected today.

Marine

A high pressure surface ridge over the Hawaiian Islands and a weakening stationary front northwest of Kauai will keep mostly stable weather conditions and light to gentle southerly winds in the forecast through the weekend. Shower activity will begin to increase over the islands of Kauai and Oahu early next week as a low pressure system develops northwest of the state.
Seas and surf will remain on the small side today. A medium period north (340-360) swell will build Sunday and peak Monday, boosting surf heights along north facing shores. For the south facing shores, a small long period swell will build Monday, producing near head high surf by Tuesday, and then slowly fade into Wednesday.
East swell energy will get into the action from Wednesday onward building surf heights along east facing shores as a large east to west 15 to 25 kt fetch area sets up just east of the island chain.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov