Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 83 to 88 near the shore to around 74 above 3000 feet. Northeast winds around 10 mph shifting to the south up to 10 mph in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows around 70 near the shore to around 60 above 3000 feet. Light winds. Chance of rain 20 percent.

Sunday: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs around 86 near the shore to around 74 above 3000 feet. Light winds. Chance of rain 40 percent.

South Kaua’i

Today: Sunny. Isolated showers in the afternoon. Highs around 85. Northeast winds around 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 68 to 73. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Sunday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 82 to 87. Light winds becoming east around 10 mph in the afternoon. Chance of rain 40 percent.

Kaua’i Mountains

Today: Sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 73 to 79 in the valleys to around 65 above 4000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows around 65 in the valleys to around 57 above 4000 feet. Northeast winds up to 10 mph. Chance of rain 30 percent.

Sunday: Partly sunny with scattered showers. Highs 73 to 79 in the valleys to around 66 above 4000 feet. Light winds becoming east around 10 mph in the afternoon. Chance of rain 50 percent.

North Kaua’i

Today: Sunny. Isolated showers in the afternoon. Highs 76 to 85. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 63 to 72. East winds up to 10 mph. Chance of rain 20 percent.

Sunday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 76 to 85. East winds up to 10 mph. Chance of rain 40 percent.

East Kaua’i

Today: Sunny. Isolated showers in the afternoon. Highs 74 to 85. Northeast winds around 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows 62 to 74. Northeast winds up to 10 mph. Chance of rain 30 percent.

Sunday: Partly sunny with scattered showers. Highs 74 to 85. East winds up to 10 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Expect rather light winds through the forecast period, allowing for development of a land breeze/sea breeze pattern. Light to moderate trade winds may briefly return today through Monday. Other than a slight increase in windward showers for Kauai this weekend as a front approaches and stalls, expect rather dry conditions throughout the next seven days.

Discussion

The subtropical ridge continues to straddle the main Hawaiian Islands this morning, keeping winds rather light. Overnight cooling has cleared skies of earlier scattered to patchy broken low clouds. Radar shows no shower activity across the area. Latest soundings show a dry and stable airmass, with 0.9 to 1.3 inches of PW and positive lifted index values. Weakening inversions in the 4500 to 5500 feet layer cap vertical cloud development and limit total rainfall.
A front north of the islands moved closer to Kauai throughout the night and is now 50 to 100 miles away, still too far to impact local weather this morning. Models show this front will stall over or just north of Kauai before dissipating. The probability for showers across Kauai over the next day or two depends on where the front is prior to its dissipation. Elsewhere, fairly dry conditions will prevail through the next week. Trade winds may briefly become light to moderate later today into Monday. However, winds will still be light enough to allow for development of afternoon sea breezes across leeward areas, followed by land breezes each night. Beyond Monday, lighter winds are expected across the islands as another ridge moves south over the state and lingers for several days.

Aviation

Winds will remain light and variable early this morning ahead of a weak cold front approaching from the northwest. Winds will increase slightly to bring light to moderate trades today and tonight. Even with the slight increase in wind speeds, local sea breezes are still expected to develop and bring increased inland cloud cover and spotty showers this afternoon, especially for the more protected areas. Then weak land breezes will likely develop again this evening, which will help to clear out some of the cloud cover overnight. However, as the front approaches, stalls and further weakens near Kauai tonight, northeast winds, increased cloud cover and light rainfall may develop along the north facing slopes of Kauai.
Brief MVFR ceilings or visibilities are possible in showers, otherwise VFR conditions will prevail.
No AIRMETs are in effect and none are expected through the next 24 hours.

Marine

An approaching weakening front will diminish by Sunday as it stalls out just north of Kauai. Light to locally moderate trade winds will briefly return across the region from Sunday night through Monday. A light wind pattern will continue through much of the week with light southeasterly winds developing from Tuesday onward.
Overlapping medium period north to northwest swells will keep small surf along north and west facing shores into early next week. The current north-northwest (330 degree) medium period swell will hold into Saturday. A reinforcing north-northwest (340 degree) swell will arrive late Saturday night, boosting surf a from Sunday into Monday. Another small medium period north- northwest (330-350 degree) swell builds in by next week Wednesday.
A series of late season south swells will keep surf heights boosted along south facing shores into early next week. Longer period south swells (180-190 degrees) will move through the area through Monday. A background medium period southwest (230 degree) swell will build Saturday night and linger into Monday. In the extended time range yet another late season long period swell arriving by Thursday will keep surf heights elevated along south facing shores into next weekend.
Surf will remain small along east facing shores into early next week due to locally light winds and the lack of a significant fetch of trade winds upstream of the islands.
Higher than predicted water levels have been observed across the Hawaiian Islands this past week. Minor coastal flooding is possible during the early morning high astronomical tides into early next week, with Monday seeing the highest tides of the period. A Coastal Flood Statement continues for all vulnerable coastal areas through Tuesday morning.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov