Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly sunny. Breezy. Highs around 87 near the shore to around 77 above 3000 feet. East winds up to 20 mph.

Tonight: Partly cloudy. Breezy. Lows 70 to 75 near the shore to around 61 above 3000 feet. Northeast winds up to 20 mph.

Thursday: Mostly sunny. Breezy. Highs around 87 near the shore to around 77 above 3000 feet. East winds up to 20 mph.

South Kaua’i

Today: Partly sunny. Breezy. Isolated showers in the morning. Highs around 86. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Tonight: Breezy. Mostly cloudy with isolated showers. Lows 68 to 74. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Thursday: Partly sunny. Breezy. Isolated showers in the morning. Highs around 86. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Kaua’i Mountains

Today: Mostly cloudy. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 73 to 81 in the valleys to around 70 above 4000 feet. East winds 10 to 25 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 61 to 66 in the valleys to around 56 above 4000 feet. East winds up to 25 mph. Chance of rain 50 percent.

Thursday: Mostly cloudy. Breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 73 to 81 in the valleys to around 70 above 4000 feet. East winds up to 25 mph increasing to 10 to 25 mph in the afternoon. Chance of rain 50 percent.

North Kaua’i

Today: Breezy. Partly sunny with isolated showers. Highs 76 to 86. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 20 percent.

Tonight: Breezy. Mostly cloudy with isolated showers. Lows 64 to 74. East winds up to 20 mph. Chance of rain 20 percent.

Thursday: Breezy. Partly sunny with isolated showers. Highs 76 to 86. East winds up to 20 mph. Chance of rain 20 percent.

East Kaua’i

Today: Breezy. Partly sunny with isolated showers. Highs 75 to 86. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Tonight: Breezy. Mostly cloudy with isolated showers. Lows 62 to 75. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Thursday: Breezy. Mostly cloudy with isolated showers. Highs 75 to 86. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Seasonable trade winds will be breezy to windy through early next week, delivering brief showers mainly to windward areas. In the short term, trade showers are expected to be fewer than normal, with increased shower coverage possible later in the week as a trough aloft moves over the area from the east.

Discussion

Guidance remains in good agreement and shows the locally strong and gusty trades lingering into early next week as the surface ridge remains strong to the north. Despite the mostly dry, seasonable trade wind pattern in place, expect periods with brief showers passing through, primarily favoring windward and mauka areas. Early morning satellite imagery and data showed some low-level moisture moving in from the east, which supports the windward shower coverage this morning. Some of these showers could briefly reach the dry leeward areas of the smaller islands through the early morning hours. Otherwise, mostly dry conditions are anticipated through Thursday.
A weak mid- to upper-level trough approaching from the east will move through late Thursday through Friday. A cool pocket aloft associated with this upper feature, combined with the gusty trades, could lead to a period of enhanced windward and mauka shower coverage.

Aviation

Breezy to locally windy trades will continue for the next couple of days. Low cigs and SHRA will favor windward and mauka areas. Expect mainly VFR with brief MVFR conds under passing SHRA.
AIRMET Sierra is in effect for mtn obsc for windward Molokai, Maui and the Big Island.
AIRMET Tango for mtn lee turb will remain in effect for the next couple of days.

Marine

As the weak low far north of the state weakens and moves away from the state, high pressure will strengthen and will result in the trade winds strengthening during the next 24 hours. Trade winds should strengthen this afternoon with near gales expected for some of the windier channels around Maui County and the Big Island. With the trade winds expected to strengthen throughout the day today, the Small Craft Advisory (SCA) has been expanded to cover all Hawaiian Waters through Thursday. The trade winds will continue to remain strong through most of the weekend and the SCA should be extended beyond Thursday.
The current small south-southwest swell should slowly decline today and fade out on Thursday. Another small pulse from the south-southwest is possible late Thursday into Friday. A storm- force low passed east of New Zealand this past weekend into Monday. Seas in excess of 40 feet was seen on the altimeter pass early yesterday morning, but by then the winds were aimed east of Hawaii. Nonetheless, we should see a decent run of south-southwest swells this weekend through the first half of next week. Surf heights will likely reach the advisory threshold of 10 feet along south facing shores during its peak Sunday into Monday then gradually decline through the first half of next week.
Choppy surf along east facing shores will steadily increase during the middle to second half of the week in response to the building trade winds locally and upstream of the state. Surf along north facing shores will remain minimal with select exposures catching some windswell wrap.

HFO Watches/Warnings/Advisories

Wind Advisory until 6 AM HST Thursday for Big Island Summits.
Small Craft Advisory until 6 PM HST Thursday for all Hawaiian waters,

Data Courtesy of NOAA.gov