Photo Credit: Braden Jarvis

West Kaua’i

Today: Mostly sunny with isolated showers. Highs around 82 near the shore to around 72 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows around 73 near the shore to around 62 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers. Highs around 83 near the shore to around 73 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

South Kaua’i

Today: Partly sunny. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 81. Northeast winds 15 to 20 mph. Chance of rain 70 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows around 73. Northeast winds 15 to 20 mph. Chance of rain 50 percent.

Sunday: Partly sunny with numerous showers in the morning, then mostly sunny with scattered showers in the afternoon. Highs around 82. Northeast winds around 15 mph. Chance of rain 70 percent.

Kaua’i Mountains

Today: Breezy. Frequent showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 70 to 76 in the valleys to around 65 above 4000 feet. East winds 10 to 20 mph. Chance of rain near 100 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then numerous showers after midnight. Lows around 66 in the valleys to around 58 above 4000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

Sunday: Partly sunny. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 71 to 77 in the valleys to around 66 above 4000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

North Kaua’i

Today: Mostly cloudy with frequent showers in the morning, then mostly sunny with scattered showers in the afternoon. Highs 72 to 81. East winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 90 percent.

Tonight: Mostly cloudy with scattered showers. Lows 66 to 74. East winds up to 15 mph. Chance of rain 50 percent.

Sunday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 73 to 82. East winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 50 percent.

East Kaua’i

Today: Cloudy with frequent showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 72 to 82. Northeast winds 10 to 15 mph. Chance of rain 90 percent.

Tonight: Mostly cloudy with scattered showers. Lows 64 to 75. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Sunday: Partly sunny with scattered showers. Highs 73 to 83. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Stable and breezy trade wind weather will prevail through late next week, with bands of low clouds and showers occasionally moving through the islands. The showers will favor windward slopes and coasts, particularly at night and during the early morning hours, with a few showers reaching leeward areas at times.

Discussion

Currently at the surface, a 1027 mb high is centered around 700 miles northwest of Kauai, and is driving moderate to breezy trade winds across the island chain early this morning. Infrared satellite imagery shows variably cloudy conditions across the state, with cloud coverage the highest over windward and mauka areas. Radar imagery shows scattered to numerous showers moving into windward areas, with a few of these showers spilling over into leeward locales. Main short term focus revolves around rain chances during the next couple days.
High pressure northwest of the state will shift east and merge with a new building high to the distant northeast of the islands by late Sunday. This high will weaken during the first half of next week, while a new and stronger high settles in to the distant north of the islands. Breezy trade winds will prevail through the period, and could become quite strong late next week as the high to the north of the state moves southward and closer to the island chain.
As for the remaining weather details, fairly typical trade wind weather will prevail during the next week or so, with bands of low clouds and showers occasionally moving through the islands with the trades. Showers will favor windward slopes and coasts, particularly at night and during the early morning hours, with a few showers reaching leeward areas at times as well.

Aviation

Breezy trade winds will continue through the weekend with brief showers lingering in the forecast primarily affecting windward and mountain areas. Ridging aloft is producing inversion heights between 7,000 to 8,000 feet keeping periods of showers in the island forecast. A band of moisture from dissipated front will continue to affect western end of the island chain through the morning hours.
AIRMET Sierra for mountain obscuration remains in effect for Kauai this morning. These low cloud CIGs will likely decrease a few hours after sunrise. Elsewhere, isolated MVFR conditions will be confined to windward areas, while VFR will dominate leeward airfields.
AIRMET Tango for moderate low level turbulence remains in effect this morning due to breezy trade wind flow over and down wind of all island mountains.

Marine

High pressure to the northwest of the state will shift to the north of the state this weekend then hold in place and intensify over the coming week. A Small Craft Advisory (SCA) remains in effect for the windier waters around Maui County and the Big Island and will likely remain so for the foreseeable future. In the extended, there is growing confidence for trades to further strengthen as a northeast Pacific high becomes increasingly dominant. Strong trade winds could become widespread during the second half of next week with even gales possible for select channels.
The current medium period NNW (320-350 degree) swell will gradually decline through Monday. A moderate NW (320 degree) swell is expected to take its place on Monday and will likely peak near advisory levels Monday evening. This swell will be followed by a slightly larger NW (320 degree) swell on Wednesday, which should produce advisory level surf for N and W facing shores late next week.
Surf along east-facing shores will remain rough and choppy through the middle of next week due to the breezy trade winds. Long range models are showing a significant increase of windswell towards the latter half of next week due to a large fetch of strong trade winds setting up over and upstream of the state. Surf could reach the advisory threshold of 10 ft by the end of the upcoming work week.
Surf along south-facing shores will remain small and near the seasonal average through the middle of next week. Tiny long-period pulses will be possible over the next few days.
Also with the peak monthly tides coming up towards the latter half of next week (Nov 14th to Nov 18th) we could see coastal inundation impacts during the early morning hours along all coastlines. The large windswell combined with the peak monthly tides could cause greater impacts along windward shores.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST Tuesday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov