Photo Credit: Braden Jarvis

West Kaua’i

Today: Sunny. Highs 82 to 87 near the shore to around 73 above 3000 feet. Light winds.

Tonight: Mostly clear with isolated showers. Lows 63 to 69 near the shore to around 57 above 3000 feet. Light winds. Chance of rain 20 percent.

Saturday: Sunny. Scattered showers in the morning. Highs around 84 near the shore to around 73 above 3000 feet. Light winds becoming west up to 10 mph in the afternoon. Chance of rain 50 percent.

South Kaua’i

Today: Mostly sunny. Isolated showers in the morning. Highs 78 to 86. Northeast winds around 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy with scattered showers. Lows around 68. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Saturday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 77 to 85. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Kaua’i Mountains

Today: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 70 to 80 in the valleys to around 64 above 4000 feet. Light winds. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then showers likely after midnight. Lows 59 to 65 in the valleys to around 54 above 4000 feet. Light winds becoming east up to 10 mph after midnight. Chance of rain 70 percent.

Saturday: Mostly cloudy with showers likely in the morning, then mostly sunny with scattered showers in the afternoon. Highs 70 to 80 in the valleys to around 63 above 4000 feet. East winds up to 15 mph. Chance of rain 70 percent.

North Kaua’i

Today: Mostly sunny with isolated showers. Highs 73 to 84. East winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 60 to 69. Southeast winds up to 10 mph. Chance of rain 50 percent.

Saturday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 73 to 84. Southeast winds up to 10 mph shifting to the east in the afternoon. Chance of rain 50 percent.

East Kaua’i

Today: Mostly sunny with isolated showers. Highs 70 to 83. Northeast winds up to 10 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy with scattered showers. Lows 60 to 72. North winds up to 10 mph in the evening becoming light. Chance of rain 50 percent.

Saturday: Mostly cloudy with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 70 to 83. Northeast winds up to 10 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Moderate trade winds will continue today, then weaken tonight through the first half of next week. Conditions should remain fairly stable with passing low clouds and light showers. Rain chances increase mid to late next week as a front moves slowly across the islands.

Discussion

High pressure far north-northeast of the state will keep moderate trade winds across the islands today. Conditions early this morning remain fairly dry under stable flow with passing clouds and showers over mainly windward and mauka areas. This morning's 12Z soundings at Lihue and Hilo show the trade wind inversion around 5000 ft so most showers that develop should be light.
Winds look to gradually weaken tonight as a weak front approaches the state, then stalls and dissipates northwest of Kauai. Expect mostly dry and stable weather to continue through Saturday, with the highest chance of rain along windward and mauka areas during the overnight and early morning hours.
Lighter winds are then expected to develop across the state by Sunday and continue through early next week as the local pressure gradient across the islands weakens. This will allow for the development of localized daytime sea breezes and nighttime land breezes Sunday into Monday. Clouds and showers will generally focus over interior areas during the afternoons as the sea breezes develop.
A slightly stronger front looks to then approach the state towards the middle of next week. Will see a slight uptick in rain chances across the state as pre-frontal bands quickly move across the area Wednesday. Guidance continues to show this front reaching Kauai by Thursday then either stalling or slowly moving across the state and dissipating into Friday. Moderate to locally breezy trade winds look to return next weekend.

Aviation

Moderate trades will continue through the rest of today and weaken through the first half of next week. A band of moisture is riding in on the trades and may cause SHRA and low cigs along windward and mauka locations. MVFR conds expected in SHRA but otherwise VFR should prevail.
AIRMET Sierra is in effect for mtn obsc abv 020 for windward Big Island and abv 025 for the rest the island chain. Conds should improve later this morning morning.

Marine

Trade wind speeds have weakened to gentle to locally fresh as a front approaches then stalls and weakens northwest of the coastal waters this weekend. Winds will shift out of the southeast by Sunday, but will weaken enough for localized daytime sea breezes and nighttime land breezes Sunday into Monday. Another front approaching from the northwest early next week will keep gentle south winds in place.
The NDBC offshore buoy 51101 showed a rapid rise in swell overnight, with swell height spiking like a hockey stick. This translates to a similarly sharp increase in surf along north and west facing shores today. A High Surf Warning (HSW) has been issued starting this morning as this large to extra-large northwest swell (310-320 deg) will fill in today and peak this evening. Expect the potential for periodic overtopping of vulnerable coastal roadways, wave runup to coastal properties especially around high tide early Saturday morning. A Small Craft Advisory (SCA) for seas 10 feet or greater over majority of the coastal waters has also been issued starting this morning and expected to hold through Saturday.
Due to the westerly component of this swell a High Surf Advisory (HSA) has been issued for west- facing shores of the Big Island starting at noon through Saturday. A gradual downward trend will follow over the weekend, with surf potentially dipping below the advisory levels by the end of the weekend. Into the extended forecast, a stretch of elevated surf is expected with overlapping northwest pulses ranging from large to potentially extra-large surf.
Surf along east facing shores will remain elevated through the weekend due to the lingering short-period north-northeast swell. Early next week east facing shores look to remain small.
Surf along south facing shores will see an uptick today through the first week of December from the southwest in a series of consecutive pulses, ranging from small to moderate surf with the peak days looking to be next week Monday and Tuesday.

Fire weather

Critical fire weather conditions not expected through early next week as winds remain below warning thresholds. Daytime relative humidity may briefly touch critical levels over drier leeward areas into next week.

HFO Watches/Warnings/Advisories

High Surf Warning until noon HST Saturday for Niihau, Kauai Leeward, Waianae Coast, Oahu North Shore, Maui Windward West, Kauai North, Koolau Windward, Molokai Windward, Molokai North, Molokai West, Windward Haleakala.
High Surf Advisory from noon today to noon HST Saturday for Kona, Kohala.
Small Craft Advisory until 6 PM HST Saturday for Kauai Northwest Waters, Kauai Windward Waters, Kauai Leeward Waters, Kauai Channel, Oahu Windward Waters, Kaiwi Channel, Maui County Windward Waters, Big Island Windward Waters.
Small Craft Advisory until 6 PM HST Saturday for Alenuihaha Channel.

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