Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly sunny. Highs around 91 near the shore to around 79 above 3000 feet. East winds up to 15 mph.

Tonight: Partly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows 73 to 78 near the shore to around 64 above 3000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Saturday: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs around 91 near the shore to around 79 above 3000 feet. East winds up to 10 mph. Chance of rain 50 percent.

South Kaua’i

Today: Partly sunny. Isolated showers in the morning. Highs around 88. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy with scattered showers. Lows 71 to 77. Northeast winds 10 to 15 mph. Chance of rain 50 percent.

Saturday: Partly sunny with scattered showers. Highs around 88. East winds 10 to 15 mph. Chance of rain 50 percent.

Kaua’i Mountains

Today: Mostly cloudy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 78 to 85 in the valleys to around 69 above 4000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then frequent showers after midnight. Lows 64 to 69 in the valleys to around 59 above 4000 feet. East winds 10 to 15 mph. Chance of rain 60 percent.

Saturday: Mostly cloudy. Frequent showers in the morning, then scattered showers in the afternoon. Highs 78 to 85 in the valleys to around 69 above 4000 feet. East winds 10 to 15 mph. Chance of rain 60 percent.

North Kaua’i

Today: Partly sunny with isolated showers. Highs 81 to 90. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 67 to 77. East winds 10 to 15 mph. Chance of rain 60 percent.

Saturday: Partly sunny. Numerous showers in the morning, then scattered showers in the afternoon. Highs 81 to 90. East winds 10 to 15 mph. Chance of rain 60 percent.

East Kaua’i

Today: Partly sunny with isolated showers. Highs 81 to 89. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 20 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 65 to 78. Northeast winds 10 to 15 mph. Chance of rain 60 percent.

Saturday: Partly sunny. Numerous showers in the morning, then scattered showers in the afternoon. Highs 81 to 89. East winds 10 to 15 mph. Chance of rain 60 percent.

Detailed Forecast

Synopsis

Breezy easterly trades will continue through this afternoon, then ease slightly over the weekend as a high to the north weakens. Expect mostly dry conditions with scant rainfall favoring windward and mauka locations at night and during early morning hours. Shower coverage may increase slightly this weekend as an upper disturbance moves over the state.

Discussion

High pressure far north northeast of the main Hawaiian Islands drives breezy conditions across local waters this morning. Radar and satellite loops show scattered to patchy broken low clouds and showers favoring windward and mauka areas. Models show breezy trades will persist through this afternoon as the high remains anchored. Expect stable and rather dry conditions to prevail. Scant showers that do form will remain confined to windward and mauka locations. Expect very few showers to make it over leeward locations. The exception will be over leeward areas of the Big Island through the afternoon hours, where sea breezes may be enough to trigger a few showers.
An upper trough, combined with the high to the north weakening, will increase windward shower coverage and decrease trade wind speeds this weekend. Models show this pattern persisting into early next week, followed by a return of drier air and breezy trades as the high strengthens again Tuesday through midweek.

Aviation

Moderate to breezy trade winds will continue into the weekend, with clouds and showers favoring windward and mauka locations. Although VFR conditions will prevail, expect periods with MVFR CIGs/VSBYs over windward areas, especially overnight through the morning hours in passing showers.
AIRMET SIERRA for mountain obscuration is now in effect for the windward areas of Oahu and the Big Island, which may persist through the early morning hours today.
AIRMET TANGO remains in effect for moderate lee turbulence below 100. This will likely hold through the day today, then become canceled tonight into Saturday as the trades slightly ease.

Marine

High pressure north-northeast of the state will keep fresh to locally strong trade winds blowing through this afternoon, and a Small Craft Advisory (SCA) remains in effect for the typical windy waters around Maui and the Big Island. The trades may ease just below SCA thresholds tonight through Monday as the pressure gradient over the area slackens a bit. Guidance shows the high strengthening to the distant northeast Tuesday through the middle of next week, ramping trades back up into the fresh to locally strong range once again.
East facing shores will continue to subside as the tail end of the Tropical Cyclone Hilary swell exits the area. Surf then trends up toward the summertime average by the middle of next week as trades restrengthen.
North and west shores remain flat through the weekend with a small bump Sunday night through early next week as a tiny medium period northwest swell traverses area waters before fading out during the middle of next week.
Surf along south facing shores will remain small through Monday, with mainly background southerly swells moving through. This will be followed by a modest bump mid-week as medium- long period energy emanating out of the southwest reaches the area.

Fire weather

There remains an elevated fire danger through this afternoon due to a combination of very dry fuels and breezy trades. Although the winds are not expected to exceed the critical levels required for a warning, any fire that starts could become difficult to control. The threat should lower Friday evening through Monday as the winds ease slightly.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST this evening for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov