Photo Credit: Sebastien Gabriel

West Kaua’i

Today: Sunny. Highs 82 to 87 near the shore to around 74 above 3000 feet. North winds up to 10 mph in the morning becoming light.

Tonight: Mostly clear. Lows 62 to 67 near the shore to around 55 above 3000 feet. Light winds becoming northeast up to 10 mph after midnight.

Thanksgiving Day: Sunny. Highs 82 to 87 near the shore to around 73 above 3000 feet. North winds up to 10 mph.

South Kaua’i

Today: Mostly sunny. Breezy. Isolated showers in the morning. Highs 79 to 87. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Isolated showers after midnight. Lows around 67. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Thanksgiving Day: Mostly sunny. Breezy. Isolated showers in the morning. Highs 78 to 85. Northeast winds 10 to 20 mph. Chance of rain 20 percent.

Kaua’i Mountains

Today: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 72 to 81 in the valleys to around 65 above 4000 feet. Northeast winds up to 10 mph. Chance of rain 40 percent.

Tonight: Partly cloudy with isolated showers in the evening, then mostly cloudy with scattered showers after midnight. Lows 57 to 64 in the valleys to around 53 above 4000 feet. Northeast winds up to 15 mph. Chance of rain 40 percent.

Thanksgiving Day: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 71 to 80 in the valleys to around 64 above 4000 feet. East winds up to 15 mph. Chance of rain 40 percent.

North Kaua’i

Today: Mostly sunny. Isolated showers in the morning. Highs 74 to 85. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 59 to 67. Southeast winds up to 10 mph. Chance of rain 20 percent.

Thanksgiving Day: Mostly sunny with isolated showers. Highs 73 to 84. East winds up to 15 mph. Chance of rain 20 percent.

East Kaua’i

Today: Mostly sunny. Isolated showers in the morning. Highs 72 to 84. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 59 to 70. North winds around 10 mph. Chance of rain 20 percent.

Thanksgiving Day: Mostly sunny with isolated showers. Highs 71 to 83. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Stable and rather dry northerly winds will shift out of the northeast today, producing brief showers over mainly north and windward slopes. Winds will strengthen a bit and shift from a more easterly trade wind direction from Thursday into Saturday. Expect a few more clouds and brief passing overnight to early morning showers, mainly over windward and mountain areas as the trade winds return. Trade winds will decline Sunday and will be disrupted early next week.

Discussion

The leading edge of a return to moderate trade winds shows up on this mornings satellite imagery and local radar as a surface trough with a narrow cloud band moving in from the north into the islands of Molokai and Maui at 3:30 AM HST. Based on the motion of this cloud band and ASCAT scatterometry satellite data, northeasterly winds around 15 to 20 mph will develop as this convergence boundary washes through each island through the morning hours. A brief boost in clouds and a few showers will develop as this wind speed convergence boundary swiftly passes through each island.
Outside of the slight boost in clouds and few showers along the approaching surface trough, we expect the strong subsidence aloft will keep temperature inversion heights in the roughly 4,000 to 5,000 foot range through tonight, and then around the 5,000 to 7,000 foot range thereafter. Resulting in limited low clouds in this stable pattern with mostly isolated to scattered rainfall coverage over the windward mountain peaks of each island, near zero chances for rainfall elsewhere. Relatively dry moisture levels across the state will allow for increased radiational cooling (releasing heat into space),resulting in below normal overnight to early morning temperatures statewide through Thursday morning.
Trade winds will increase slightly and veer from a more easterly direction from Thursday into the weekend allowing for a small increase to humidity levels. Overall atmospheric conditions will remain fairly stable and dry weather trends will continue into the upcoming weekend.
Trade winds will transition to light winds with land and sea breezes next week from Sunday through next Wednesday with limited clouds and showers as the high pressure ridge weakens due to an approaching cold front. The next best chance for more widespread rainfall will develop by next week Thursday as a weakening cold front moves into the Hawaiian Islands from the northwest with the latest model projections showing the frontal band stalling out somewhere between the western islands of Kauai and Oahu. Rainfall with this weakening front will mainly fall along the frontal zone. How far eastward down the island chain is less certain at this point in time.

Aviation

Light north-northeast winds will prevail through the forecast period and give way to localized sea breezes and land breezes in the most sheltered areas. Shower activity essentially nil through the afternoon.
No AIRMETs in effect.

Marine

Light to moderate north to northeast winds will veer out of the northeast and increase into the moderate to fresh category today, then out of the east-northeast through the second half of the week as high pressure builds north of the area. Winds may ease next weekend and into early next week with a potential front passing to the north. Seas will potentially exceed the 10 ft Small Craft Advisory level Friday through Saturday for waters exposed to large west-northwest swells.
Surf along exposed north and west facing shores will remain small through Thursday, due to a mix of a medium-period north-northwest swell and a lingering, shorter period north-northeast swell. A developing hurricane force low around 1500 NM northwest of the islands will send a large, long-period west-northwest swell through the area Friday into the weekend, potentially driving surf heights to warning levels late Friday into early Saturday as it peaks. A gradual downward trend will follow over the weekend, with surf potentially dipping below the advisory levels by the end of the weekend.
Surf along east facing shores will remain up through the weekend due to the lingering short-period north-northeast swell and a short-period northeast swell expected late Thursday through the weekend. Heights will peak Friday into the weekend below the advisory level as this northeast swell arrives and peaks.
Surf along south facing shores will remain near seasonal averages this week, driven by a mix of short-period southeast and background long period south-southwest swells. An upward trend is expected this weekend through the first week of December, due to an active pattern evolving within our swell window near New Zealand.

Fire weather

We do not foresee any critical fire weather conditions developing through the first half of next week as wind speeds will remain below critical thresholds. Dry relative humidity levels may briefly touch fire weather criteria over drier leeward zones this week.

HFO Watches/Warnings/Advisories

None.

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