Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly sunny with isolated showers. Highs around 89 near the shore to around 77 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy with isolated showers. Lows around 71 near the shore to around 62 above 3000 feet. Northeast winds up to 15 mph. Chance of rain 20 percent.

Wednesday: Mostly sunny with isolated showers. Highs around 89 near the shore to around 76 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

South Kaua’i

Today: Partly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 82 to 88. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 72. Northeast winds 10 to 15 mph. Chance of rain 40 percent.

Wednesday: Partly sunny. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 82 to 89. Northeast winds 10 to 20 mph. Chance of rain 50 percent.

Kaua’i Mountains

Today: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Highs 73 to 84 in the valleys to around 67 above 4000 feet. East winds up to 15 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 65 to 71 in the valleys to around 59 above 4000 feet. East winds up to 15 mph. Chance of rain 70 percent.

Wednesday: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Highs 73 to 84 in the valleys to around 66 above 4000 feet. East winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 70 percent.

North Kaua’i

Today: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 76 to 89. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers. Lows 65 to 74. East winds up to 15 mph becoming around 10 mph after midnight. Chance of rain 50 percent.

Wednesday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 76 to 89. East winds up to 15 mph. Chance of rain 50 percent.

East Kaua’i

Today: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 74 to 86. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 65 to 75. Northeast winds 10 to 15 mph. Chance of rain 70 percent.

Wednesday: Partly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 74 to 85. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

A broad high pressure ridge will remain locked in place north of the Hawaiian Islands into the upcoming weekend. Trade wind speeds will range from moderate to breezy for most days with slight decreasing wind speed trends from Thursday onward. Fairly stable conditions will produce mostly brief passing showers over windward and mountain areas.

Discussion

A broad subtropical ridge north of the island chain will keep moderate to breezy trade winds in the forecast lasting into the middle of the week with slight decreasing wind speed trends from Thursday onward. A slight ripple in the force is shown on infrared satellite imagery this evening as a band of clouds continues to move into the Big Island. This north to south oriented cloud band is associated with a weak low level trough riding into the islands on the easterly trade winds. Expect a slight increase in clouds and showers through the early morning hours across the windward slopes of Molokai, Maui and the Big Island, and then slightly increasing shower activity over windward Oahu and Kauai later tonight; as these unsettled clouds drift into the mountains of each island. A few high level cirrus ice crystal clouds are drifting over the state for the next few days, enhancing island sunrise and sunset colors.
Otherwise mostly dry conditions will prevail this week with only brief passing showers over windward and mountain areas. Shower amounts will be limited due to the strong subsidence under this high pressure ridge pattern. Trade wind thermal inversion heights will range from around 4,000 to 6,500 feet with most windward areas only seeing isolated to scattered shower coverage, favoring the overnight to early morning hours. Some exceptions may include the eastern slopes of Maui, and the windward and Kona slopes of the Big Island where periods of passing rain showers will likely continue.

Aviation

Moderate to locally breezy trade winds will continue through tonight. A band of low clouds and showers will move from east to west across the state today, bringing some MVFR cigs/vsbys to windward areas as it moves through. Conditions will improve behind the band of clouds and showers, although some showery weather may linger across Kauai through the evening hours.
AIRMET Sierra is in effect for mountain obscuration across windwardsections of Molokai, Maui and the Big Island. The AIRMET will likely need to be expanded to include Oahu later this morning.

Marine

High pressure north northeast of the state will bring fresh to strong trades through most of the week. By this weekend, the high will weaken and move off to the northeast as a trough approaches from the west and allow for trades to ease slightly across the local waters. A Small Craft Advisory has been extended through Thursday morning for the waters and channels around the Maui and The Big Island. Expect conditions in these typical windy areas to remain at or slightly below advisory levels Thursday afternoon into Friday.
No significant south swells are expected during the forecast period. However, a series of small south-southwest and southeast swells will keep south facing shores from going flat.
Flat to tiny surf conditions will continue along north and west facing shores through most of the week. East shore surf will be close to seasonal levels through late this week, as fresh to strong east northeast trades persist over and upstream of the islands. A fetch of strong northeast winds well off the California coast should bring a small, medium period, northeast swell Saturday into early next week. Some of this swell should wrap into select north facing exposures as well.
Water levels running roughly 0.5 ft higher than normal around the Big Island combined with the new moon tides could cause minor flooding issues between July 2nd and July 6th with peak water levels expected on July 4th. Our last full moon, we did receive reports of some areas of the coastline becoming inundated with the high tide such as Coconut Island and Puhi Bay. A Coastal Flood Statement will likely be needed for the Big Island near the 4th of July. For the other islands, water levels are running just a touch above normal and will likely not reach our criteria of 1 foot above the Mean Higher High Water (MHHW).

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 AM HST Thursday for the windier areas around Maui and the Big Island.

Data Courtesy of NOAA.gov