Photo Credit: Braden Jarvis

West Kaua’i

Rest Of Today: Mostly sunny. Highs around 82 near the shore to around 70 above 3000 feet. West winds 10 to 15 mph.

Tonight: Partly cloudy. Lows around 61 near the shore to around 50 above 3000 feet. Northwest winds up to 10 mph in the evening becoming light.

Thursday: Sunny. Highs around 82 near the shore to around 70 above 3000 feet. Light winds becoming southwest around 10 mph in the afternoon.

South Kaua’i

Rest Of Today: Partly sunny in the morning then becoming mostly sunny. Highs around 81. West winds 10 to 15 mph.

Tonight: Partly cloudy. Lows 57 to 62. Northwest winds 10 to 15 mph.

Thursday: Sunny. Highs around 81. West winds up to 10 mph.

Kaua’i Mountains

Rest Of Today: Partly sunny in the morning then becoming mostly sunny. Breezy. Highs 69 to 77 in the valleys to around 64 above 4000 feet. West winds up to 20 mph.

Tonight: Partly cloudy. Lows 50 to 55 in the valleys to around 44 above 4000 feet. West winds up to 15 mph.

Thursday: Mostly sunny. Highs 69 to 77 in the valleys to around 64 above 4000 feet. West winds up to 15 mph.

North Kaua’i

Rest Of Today: Partly sunny in the morning then becoming mostly sunny. Highs 74 to 81. West winds 10 to 15 mph.

Tonight: Partly cloudy. Lows 53 to 62. Southwest winds up to 15 mph in the evening becoming light.

Thursday: Sunny. Highs 74 to 81. South winds up to 10 mph shifting to the north in the afternoon.

East Kaua’i

Rest Of Today: Partly sunny in the morning then becoming mostly sunny. Highs 74 to 81. West winds up to 15 mph.

Tonight: Partly cloudy. Lows 51 to 63. West winds up to 10 mph in the evening becoming light.

Thursday: Sunny. Highs 74 to 81. West winds up to 10 mph shifting to the south in the afternoon.

Detailed Forecast

Synopsis

A weakening front will stall out and dissipate over the eastern end of the state today. Breezy conditions along with some unsettled weather will continue this morning along and in advance of the front, with improving conditions expected this afternoon. Weak high pressure building over the island chain tonight will bring a drying trend. Mostly dry weather will then persist Thursday through early next week, as winds gradually pick up out of the south and southwest ahead of another slowly approaching cold front.

Discussion

Currently at the surface, a cold front has cleared Oahu, Molokai and Lanai overnight, and now resides over Maui in a weakening state as it slows its eastward progression. Winds have shifted west-southwest and eased to moderate speeds behind the front, while breezy southerly winds continue out ahead of it. Infrared satellite imagery shows mostly cloudy conditions across much of Maui County as well as portions of Kauai and the Big Island, with partly cloudy skies elsewhere. Radar imagery shows numerous showers over Maui and approaching the Big Island, with isolated shower coverage elsewhere. Main short term focus is on timing the improving conditions into the area.
The front will continue move eastward this morning, then stall out and dissipate over the eastern islands later today. Unsettled weather will continue along and ahead of the front, with conditions improving quickly behind it from west to east. The threat for additional heavy rainfall has diminished during the last hour over Maui, therefore the Flood Watch has been cancelled. The High Wind Warning for the High Elevation summits of Maui and the Big Island remains in effect through 6 PM this evening.
Much quieter weather will have built over the island chain by this evening, as ridging surface and aloft overspreads the Aloha state easing winds to light levels. Shower activity should have ended across most of the state by early this evening, with a few light lingering showers over Maui and the Big Island. A few showers may continue over windward Big Island into Thursday, with mostly dry conditions then expected across the entire state Friday through Sunday as the winds gradually shift southerly at light to moderate levels. Increasing southerly flow in advance of the next cold front should bring an increase in showers back to the islands early next week.

Aviation

A front over Maui county will begin to stall out and dissipate today. Breezy southwesterly flow ahead of this feature may bring moderate turbulence below 9000 feet to areas north and east of the higher terrain on Maui, Lanai, and the Big Island. See AIRMET TANGO below for details.
Lines of prefrontal showers over and east of Maui county will slowly move eastward over the next several hours and reach western portions of the Big Island by day break. Expect periods of MVFR and IFR ceilings and visibility associated with this activity. Some airports in Maui County have already reported ceilings below 1000 ft AGL and visibility less than 3SM with some of the more robust rain bands. See AIRMET SIERRA below for details.
As fronts weakens and dissipates today, both shower coverage and winds are expected to slowly wane.
AIRMET SIERRA for MVFR remains in effect for Molokai above 2000 feet for tempo mountain obscuration due to clouds and showers. AIRMET SIERRA for IFR conditions also remains in effect for Lanai and Maui for tempo ceilings below 1000 feet AGL and visibility below 3SM due to clouds and showers. Conditions should improve as the day progresses.
AIRMET TANGO remains in effect over and north through east sections of Maui and Big Island mountains for tempo moderate turbulence due to breezy southwesterly flow. Conditions should improve as the day progresses.

Marine

A cold front will weaken near Maui County and the Big Island today creating a weakening trend for the fresh to strong southwesterly winds ahead of the front. Fresh westerlies have filled in behind the front. The Small Craft Advisory has been scaled back a bit due to the weakening wind trend how ever still remains for most areas due to high seas. A weak ridge will build over the state Thursday, providing a brief period of light and variable winds. Another front will pass north of the state Friday through the weekend, generating gentle to moderate south to southwest winds.
Large and rough seas will persist into Thursday. The long period north to north- northwest (340-360 degree) swell that generated a High Surf Advisory (HSA) for north facing shores will continue to subside into Thursday. A west- northwest (300-310 deg) swell will build today, on already elevated seas, and produce at surf well above the HSA level across most north and west facing shores from Kauai to Maui, as well as west facing shores of the Big Island, through Thursday. A HSA is now in effect for north facing shores, except the Big Island and for select west facing shores. For the upcoming weekend, a large, long period west- northwest (300 deg) swell will build on Saturday and produce surf around the warning level Saturday night into Sunday.
Along east facing shores, surf will remain small due to the lack of trades locally and upstream of the state. Areas exposed to the the north swell wrap will trend down today as the north swell fades. Surf along south facing shores will also trend down through the rest of the week as southwesterly wind waves and a small, long period south swell fades.

HFO Watches/Warnings/Advisories

High Surf Advisory until 6 PM HST Thursday for Niihau, Oahu North Shore, Maui Windward West, Kauai North, Molokai Windward, Molokai North, Maui Central Valley North, Windward Haleakala.
High Surf Advisory until 6 PM HST Thursday for Kauai Leeward, Waianae Coast, Kona, Kohala, Molokai West.
High Wind Warning until 6 PM HST this evening for Haleakala Summit, Big Island Summits.
Small Craft Advisory until 6 AM HST Thursday for Kauai Northwest Waters, Kauai Windward Waters, Kauai Leeward Waters, Kauai Channel, Oahu Windward Waters, Kaiwi Channel, Maui County Windward Waters, Alenuihaha Channel, Big Island Windward Waters.
Small Craft Advisory until 6 PM HST this evening for Oahu Leeward Waters, Big Island Leeward Waters.

Data Courtesy of NOAA.gov