Photo Credit: Braden Jarvis

West Kaua’i

Today: Mostly sunny. Isolated showers in the late morning and afternoon. Highs 85 to 91 near the shore to around 77 above 3000 feet. West winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy early in the evening then becoming clear. Isolated showers early in the evening. Lows around 70 near the shore to around 60 above 3000 feet. Light winds. Chance of rain 20 percent.

Friday: Sunny. Isolated showers in the late morning and afternoon. Highs 86 to 91 near the shore to around 77 above 3000 feet. Light winds becoming northeast up to 10 mph in the afternoon. Chance of rain 20 percent.

South Kaua’i

Today: Mostly sunny. Isolated showers in the late morning and afternoon. Highs 85 to 91. West winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy early in the evening then becoming clear. Isolated showers early in the evening. Lows around 70. Northeast winds up to 10 mph. Chance of rain 20 percent.

Friday: Sunny. Isolated showers in the late morning and afternoon. Highs 85 to 92. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Kaua’i Mountains

Today: Sunny early in the morning, then partly sunny with isolated showers in the late morning and afternoon. Highs 76 to 84 in the valleys to around 68 above 4000 feet. Light winds. Chance of rain 20 percent.

Tonight: Partly cloudy early in the evening then becoming clear. Isolated showers early in the evening. Lows 62 to 68 in the valleys to around 58 above 4000 feet. Light winds becoming northeast up to 10 mph after midnight. Chance of rain 20 percent.

Friday: Mostly sunny early in the morning, then isolated showers in the late morning and afternoon. Highs 76 to 83 in the valleys to around 68 above 4000 feet. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

North Kaua’i

Today: Mostly sunny. Isolated showers in the late morning and afternoon. Highs 79 to 87. Northwest winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy early in the evening then becoming clear. Isolated showers early in the evening. Lows 64 to 72. Light winds. Chance of rain 20 percent.

Friday: Sunny. Isolated showers in the late morning and afternoon. Highs 78 to 88. East winds up to 10 mph. Chance of rain 20 percent.

East Kaua’i

Today: Mostly sunny. Isolated showers in the late morning and afternoon. Highs 77 to 88. Light winds. Chance of rain 20 percent.

Tonight: Partly cloudy early in the evening then becoming clear. Isolated showers early in the evening. Lows 63 to 74. North winds up to 10 mph. Chance of rain 20 percent.

Friday: Sunny. Isolated showers in the late morning and afternoon. Highs 77 to 88. Northeast winds around 10 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Winds will remain light today, allowing afternoon sea breezes to develop. Expect increased cloud cover and spotty showers this afternoon over leeward and interior sections. Trade winds will return by this weekend as a strong high builds far northwest of the islands. An approaching front may increase shower coverage over portions of the chain early next week.

Discussion

Satellite loop shows mostly clear skies across the smaller islands this morning, with lingering broken low cloud cover noted across windward and southeast slopes of the Big Island. Radar shows isolated showers over water south of Oahu and Molokai as well as across southeast slopes of the Big Island. Overnight soundings show a seasonally dry and stable airmass, with 1.1 to 1.2 inches of PW and positive lifted index values. An inversion base near 4600 feet caps vertical cloud development and limits total rainfall.
The subtropical ridge continues to straddle the main Hawaiian Islands, keeping winds light across local waters. Models show little or no change in this pattern through today. Expect light background winds to give way to sea breezes by afternoon followed by land breezes overnight. This will set up a pattern of interior afternoon clouds and just a few spotty showers followed by clearing as evening cooling commences.
The high will rebound northward, allowing for a gradual return to trades as early as Friday. Models show locally breezy trades developing by Saturday with further strengthening possible early next week. Expect a gradual trend toward a typical distribution of trade wind clouds and showers, with both favoring windward and mauka areas. Models show an approaching front may increase shower coverage over portions of the chain early next week.

Aviation

Light and variable winds will allow sea breezes to return today, bringing increasing cloud cover and light showers over interior locations during the afternoon. Winds will increase slightly overnight tonight into Friday, but land breezes are still expected to develop, which will help to clear out some of the cloud cover and showers across the state overnight. Looking ahead, breezy trade winds will build back into the region this weekend.
There are no AIRMETs in effect, and none are anticipated today. Depending on how much moisture is transported into windward Big Island tonight, tempo mountain obscuration will be possible due to clouds and light showers, as was seen earlier this evening.

Marine

Expect the land and sea breeze regime to persist with light winds continuing today as the ridge remains over the area and a front passes to the north. Moderate to fresh trades are forecast to return Friday, then reach the fresh to strong category over the weekend through early next week as strong high pressure builds north of the area behind the front. The tail-end of the front is forecast to drift southward into the western end of the state beginning Sunday, which will potentially translate to strong trades and rough seas impacting most waters. This will lead to a Small Craft Advisory as early as Friday night for the typically windier channels and waters around Maui County/BI, then for most marine zones Saturday night through early next week.
Surf along exposed north and west facing shores quickly increased overnight as a larger than predicted north-northwest (330-340 degrees) swell filled in. Observations at the buoys have since leveled off and begun to trend back down toward predicted levels this morning. Surf will respond and hold through the morning hours today, then ease later this afternoon through Friday. A fresh, north-northwest swell similar to the current one is forecast to arrive late Friday and linger into the weekend, which will keep the surf up for exposed north and west facing shores. This pattern will continue early next week with a similar source arriving Sunday.
Surf along south facing shores will briefly trend down today, but should rise slightly Friday into the weekend as a new south- southwest (200 degrees) swell arrives and moves through.
Surf along east facing shores will trend up over the weekend and become rough through early next week as strong trades return.
Water levels continue to run much higher than predicted over the western end of the state, which will persist well into November. Although minor saltwater inundation can't be ruled out through Friday during the peak daily high tide cycle (early morning), water levels lowering over the weekend should reduce any impacts.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov