West Kaua’i

Today: Sunny. Highs 85 to 93 near the shore to around 77 above 3000 feet. East winds up to 10 mph shifting to the south in the afternoon.

Tonight: Mostly clear with isolated showers. Lows 71 to 76 near the shore to around 62 above 3000 feet. East winds up to 10 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers. Highs 86 to 92 near the shore to around 78 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

South Kaua’i

Today: Mostly sunny with isolated showers. Highs 83 to 91. East winds 10 to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 74. East winds 10 to 15 mph. Chance of rain 30 percent.

Sunday: Mostly sunny with isolated showers. Highs 83 to 91. East winds 10 to 15 mph. Chance of rain 20 percent.

Kaua’i Mountains

Today: Mostly sunny with scattered showers. Highs 77 to 85 in the valleys to around 68 above 4000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows 64 to 70 in the valleys to around 59 above 4000 feet. East winds up to 15 mph. Chance of rain 40 percent.

Sunday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 77 to 85 in the valleys to around 68 above 4000 feet. East winds up to 10 mph. Chance of rain 40 percent.

North Kaua’i

Today: Mostly sunny with isolated showers. Highs 79 to 88. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 66 to 74. East winds up to 10 mph. Chance of rain 20 percent.

Sunday: Mostly sunny with isolated showers. Highs 79 to 88. Southeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 20 percent.

East Kaua’i

Today: Mostly sunny with isolated showers. Highs 75 to 88. East winds up to 10 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows 65 to 78. East winds up to 10 mph. Chance of rain 40 percent.

Sunday: Mostly sunny with isolated showers. Highs 76 to 88. East winds up to 10 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Light to moderate trades will continue through next week, with localized land and sea breezes at times. Mostly dry and stable conditions will prevail, with the exception of a brief uptick in shower activity Sunday into Monday.

Discussion

High pressure far northeast of Hawaii remains weak and displaced by a large area of low pressure. This setup will maintain light to moderate trades, with sea and land breezes developing across the state. Mid-level ridging and dry air filtering across the region will limit shower activity, supporting a dry and stable pattern. Brief showers will mainly be confined to windward and mauka areas overnight into the morning hours, though sea breezes may bring isolated light showers to some leeward and interior areas each afternoon throughout the period.
Come Sunday into Monday a weak surface low tracks south of the Big Island. Moisture associated with this low may clip the eastern half of the island chain. At the same time, an upper level low looks to stall northwest of Kauai. This combination of deeper tropical moisture and added instability, could allow for the slight enhancement of shower activity statewide, particularly from Sunday afternoon through Monday.
A stable, drier land and sea breeze pattern returns with light to moderate trades expected from Tuesday onward.

Aviation

Light to moderate trades through the weekend. Some sea/land breezes are possible. Low cigs and SHRA expected across windward and mauka locations. While MVFR conds are possible in any SHRA, VFR should prevail.
No AIRMETs are in effect.

Marine

A ridge of high pressure north of the state will gradually shift further south during the next day or so in response to a developing low far north of the state. As the ridge meanders closer to the islands our trade wind speeds will decrease with gentle to moderate trade winds expected through early next week. Winds should be light enough for localized sea breezes, especially across leeward waters.
Surf along south facing shores will remain near summer average today as reinforcing energy from the south in the 14-18 second energy bands have filled in overnight. Surf is expected to steadily decline Sunday into Monday. Surf heights will return to background levels by early next week along south facing shores.
Surf along north facing shores will see a small, short period swell expected to arrive late this weekend. This swell will be overshadowed by longer period energy out of the northwest starting Monday night of next week. This swell should peak on Tuesday and could produce surf heights near the September average of 4 to 6 feet. Daytime ASCAT showed gale-force winds with the developing low far north of the state. This should send another reinforcing pulse out of the north around the same time the northwest swell arrives. A mix of north and northwest swells are expected next Tuesday through Thursday.
Below average surf is expected to continue along east facing shores due to gentle to moderate trade winds persisting through early next week.
Peak monthly high tides combined with water levels that are running higher than predicted may lead to minor flooding along the shoreline and in low-lying coastal areas toward the end of next week. Coastal flooding may be possible around the daily peak tide, which will be during the afternoon hours.

Fire weather

Critical fire weather RH values may be approached each afternoon though next week across some leeward locations. Lighter trade winds are expected to be the limiting factor, helping to keep the state below critical fire weather thresholds. While a slight uptick in showers is possible Sunday into Monday, expect drier more stable conditions to prevail Tuesday onward. Inversion heights will typically range between 6,500 to 8,000 feet.

HFO Watches/Warnings/Advisories

None.

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