Photo Credit: Braden Jarvis

West Kaua’i

Today: Breezy. Mostly sunny with isolated showers. Highs around 90 near the shore to around 78 above 3000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows around 73 near the shore to around 63 above 3000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

Tuesday: Mostly sunny with isolated showers. Highs around 90 near the shore to around 78 above 3000 feet. East winds 10 to 15 mph. Chance of rain 20 percent.

South Kaua’i

Today: Mostly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 85 to 90. East winds 15 to 20 mph. Chance of rain 40 percent.

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows around 73. East winds around 15 mph. Chance of rain 50 percent.

Tuesday: Partly sunny with isolated showers in the morning, then mostly sunny with scattered showers in the afternoon. Highs 85 to 90. East winds around 15 mph. Chance of rain 40 percent.

Kaua’i Mountains

Today: Breezy. Partly sunny with scattered showers. Highs 76 to 85 in the valleys to around 67 above 4000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then numerous showers after midnight. Lows 64 to 70 in the valleys to around 59 above 4000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

Tuesday: Breezy. Partly sunny with scattered showers. Highs 76 to 85 in the valleys to around 67 above 4000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

North Kaua’i

Today: Breezy. Mostly sunny with scattered showers. Highs 80 to 89. East winds up to 20 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with scattered showers. Lows 66 to 75. East winds 10 to 15 mph. Chance of rain 50 percent.

Tuesday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 80 to 89. East winds 10 to 15 mph. Chance of rain 40 percent.

East Kaua’i

Today: Partly sunny with scattered showers. Highs 78 to 88. East winds 10 to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with scattered showers. Lows 65 to 78. East winds 10 to 15 mph. Chance of rain 50 percent.

Tuesday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 78 to 88. East winds 10 to 15 mph. Chance of rain 40 percent.

Detailed Forecast

Synopsis

Breezy trades will continue through the middle of the week along with typical trade wind weather. Expect showers to favor windward and mountain areas, especially at night and during early morning hours. Trades will decrease into the moderate range Wednesday and afterwards. Showers may increase next weekend as a trough approaches the state from the east.

Discussion

High pressure far northwest of the main Hawaiian Islands continues to drive locally breezy trade winds across the area this morning. Satellite and radar loops show scattered to patchy broken low clouds across windward and mauka areas, accompanied by isolated to scattered moderate showers. Earlier cloud cover across Kona slopes of the Big Island have decreased significantly since last evening, leaving only scattered low clouds to clear skies there. Overnight soundings showed a seasonally moist but stable airmass, with 1.30 to 1.45 inches of PW and positive lifted index values.
Models show the high far northwest of the islands will slide to the east into midweek. This will keep breezy trade winds in the forecast for the next few days. Typical trade wind weather will prevail, with bands of clouds and showers expected to pass across the islands from time to time, favoring windward and mauka locations. Increased cloud coverage and a few showers may develop across the Kona slopes of the Big Island from late morning through early evening each day.
Beginning sometime Wednesday, the combination of a front approaching from the northwest and the remnant trough of post- tropical cyclone Jova approaching from the east should ease the trade winds back into the moderate range. Additionally, showers could increase next weekend as this remnant trough moves through. Moderate trades are then expected through the rest of the forecast period.

Aviation

Breezy easterly trade winds will continue through the next 24 h forecast period, with clouds and showers favoring windward and mauka locations overnight through the early morning hours. Brief periods with MVFR CIGs/VSBYs are possible in passing showers.
AIRMET TANGO for moderate low-level turbulence remains in effect, and should persist into Tuesday.

Marine

Surface high pressure centered approximately 1,200 miles north northwest of the islands will gradually transition east through the middle of the week. This will create a tight enough pressure gradient down upon the state to maintain regionally fresh to locally strong easterly trades. The Small Craft Advisory is in effect for the notoriously windier zones around Maui County and Big Island through Tuesday afternoon. Trade winds are then expected to subtly weaken through mid to late week. This will be in response to both very weak troughing approaching from the north and the remnants of former Tropical Cyclone (T.C.) Jova moving in from the east.
The recent small, short period chop that was observed along east- facing shores courtesy of breezier trade flow will continue through the week. A near 4 foot, medium to long period east (80 – 100 degree) swell from former T.C. Jova is being observed at the Hilo buoy this morning. This swell is forecast to peak surf just below High Surf Advisory criteria later today and into Tuesday. South-facing shore surf will get a boost the next couple of days as a small, long period south (190 degree) swell fills in. This swell will peak surf at near seasonable waist to chest high averages today and Tuesday before declining through mid-week. Surf along north- facing shores will remain flat into the middle of the week until a small bump from a tiny, short period pulse arrives from the north Thursday. West-facing shores will also remain flat except for where south swell wraps in.

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