Photo Credit: Jason Weingardt

West Kaua’i

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs around 84 near the shore to around 71 above 3000 feet. Light winds becoming west up to 10 mph in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows around 66 near the shore to around 56 above 3000 feet. Light winds. Chance of rain 20 percent.

Friday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 84 near the shore to around 72 above 3000 feet. Light winds. Chance of rain 30 percent.

South Kaua’i

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 80 to 85. Northeast winds up to 10 mph in the morning becoming light. Chance of rain 40 percent.

Tonight: Partly cloudy with isolated showers. Lows around 65. Light winds. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs 80 to 85. Light winds. Chance of rain 20 percent.

Kaua’i Mountains

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 72 to 78 in the valleys to around 65 above 4000 feet. Light winds. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 56 to 62 in the valleys to around 52 above 4000 feet. Light winds. Chance of rain 20 percent.

Friday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 72 to 78 in the valleys to around 65 above 4000 feet. Light winds. Chance of rain 30 percent.

North Kaua’i

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 76 to 83. South winds up to 10 mph shifting to the northwest in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 59 to 68. Light winds. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs 76 to 83. Light winds. Chance of rain 20 percent.

East Kaua’i

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 75 to 83. Light winds. Chance of rain 50 percent.

Tonight: Partly cloudy with isolated showers. Lows 57 to 69. Light winds. Chance of rain 20 percent.

Friday: Mostly sunny with isolated showers. Highs 74 to 83. Light winds. Chance of rain 20 percent.

Detailed Forecast

Synopsis

A front will approach the state from the northwest, causing local winds to weaken and veer to southeasterlies. The front will stall near the western end of the state Friday into Saturday, increasing shower chances for Kauai and possibly Oahu. The front will wash out by Sunday. Another front will approach the islands near the end of the forecast period.

Discussion

A high far northeast of the main Hawaiian Islands continues to drive moderate to breezy trade flow across local waters this morning. However, the high's influence is waning as it moves eastward. Low clouds embedded within trade wind flow will continue to affect windward areas through this morning, with a few showers expected to spread to leeward areas of the smaller islands from time to time.
As the high moves farther away today, a front will approach from the northwest and local winds will gradually weaken and veer to southeasterlies. This afternoon, veering flow will cause showers to favor southeastern districts of the Big Island, while the remaining islands remain drier within the Big Island rain shadow. Expect development of localized diurnal land and sea breezes.
Models show the front will stall and weaken near the western end of the state from late Friday into Saturday. This has the potential to increase showers across Kauai and possibly Oahu throughout this period. The front wash out by Sunday. A brief stable and dry weather pattern will return, with light to moderate easterly trade winds expected from Sunday to Monday. Another front will approach the islands from the northwest Tuesday into Wednesday of next week.

Aviation

Trade winds continue to weaken this morning and has veered more southeasterly overnight due to a weak front approaching the area. Scattered showers this morning will favor north through southeast sections of the islands this morning. As the day progresses, the light to moderate east to southeast trades will give way to sea breezes, which will increase shower activity across interior and leeward areas during the afternoon. For the most part, VFR conditions are expected, but brief MVFR ceilings and visibilities are possible within showers this afternoon.

Marine

High pressure far northeast of Hawaii and will continue to move eastward as a weakening front approaches the northwest coastal waters late this week. Fresh to locally strong southeast winds will prevail today. A Small Craft Advisory (SCA) has been issued for select waters around Maui County and the Big Island due to the acceleration of the southeast flow. Winds are forecast to fall below SCA level by tonight, then become light and variable over much of the island chain Friday through Saturday, as the weakening front nears Kauai.
Current north-northwest swell continues to fade, as an overlapping small medium-period north swell will fill in today keeping surf heights elevated. A new moderate medium- period northwest swell will boost north and west facing shores as it builds in Friday afternoon into the weekend potentially reaching High Surf Advisory levels as it peaks on Saturday.
Surf along east facing shores will be rough and choppy today especially over the eastern half of the state, due to the stronger winds. A downward trend is expected through the second half of the week as the winds diminish. Small surf will continue along south facing shores with only small background swell energy in the forecast.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST this evening for Maui County Windward Waters, Alenuihaha Channel, Big Island Windward Waters, Big Island Leeward Waters.

Data Courtesy of NOAA.gov