Kauai Weather Forecast for May 08, 2023
West Kaua’i
Today: Mostly sunny. Breezy. Isolated showers in the afternoon. Highs around 83 near the shore to around 71 above 3000 feet. East winds up to 25 mph increasing to 10 to 25 mph in the afternoon. Chance of rain 20 percent.
Tonight: Breezy. Partly cloudy with isolated showers. Lows around 70 near the shore to around 59 above 3000 feet. Northeast winds up to 20 mph. Chance of rain 20 percent.
Tuesday: Breezy. Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs around 83 near the shore to around 71 above 3000 feet. East winds up to 20 mph. Chance of rain 50 percent.
South Kaua’i
Today: Breezy. Mostly sunny with isolated showers. Highs around 80. Northeast winds 15 to 25 mph. Chance of rain 20 percent.
Tonight: Partly cloudy. Breezy. Isolated showers in the evening, then scattered showers after midnight. Lows 66 to 71. Northeast winds 15 to 25 mph. Chance of rain 50 percent.
Tuesday: Partly sunny. Breezy. Scattered showers in the morning, then numerous showers in the afternoon. Highs around 80. Northeast winds 15 to 25 mph. Chance of rain 70 percent.
Kaua’i Mountains
Today: Breezy. Partly sunny with isolated showers in the morning, then mostly sunny with scattered showers in the afternoon. Highs 70 to 77 in the valleys to around 61 above 4000 feet. East winds 10 to 25 mph decreasing to up to 25 mph in the afternoon. Chance of rain 30 percent.
Tonight: Breezy. Partly cloudy with scattered showers in the evening, then mostly cloudy with numerous showers after midnight. Lows 59 to 64 in the valleys to around 52 above 4000 feet. East winds up to 25 mph. Chance of rain 70 percent.
Tuesday: Breezy. Mostly cloudy with occasional showers. Highs 70 to 77 in the valleys to around 61 above 4000 feet. East winds up to 20 mph increasing to 10 to 20 mph in the afternoon. Chance of rain 90 percent.
North Kaua’i
Today: Partly sunny in the morning then becoming mostly sunny. Breezy. Isolated showers. Highs 73 to 83. East winds 10 to 20 mph. Chance of rain 20 percent.
Tonight: Mostly cloudy with scattered showers. Lows 62 to 70. East winds up to 15 mph. Gusts up to 35 mph in the evening. Chance of rain 50 percent.
Tuesday: Partly sunny. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 73 to 83. East winds up to 20 mph. Chance of rain 70 percent.
East Kaua’i
Today: Partly sunny in the morning then becoming mostly sunny. Breezy. Isolated showers. Highs 73 to 82. Northeast winds 10 to 20 mph. Chance of rain 20 percent.
Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 59 to 72. Northeast winds 10 to 15 mph. Chance of rain 50 percent.
Tuesday: Mostly cloudy with numerous showers. Highs 73 to 82. Northeast winds 10 to 15 mph. Chance of rain 70 percent.
Detailed Forecast
Synopsis
Breezy trade winds will continue through Tuesday. Rather dry conditions will prevail today, with a band of moisture expected to increase trade wind showers late tonight and Tuesday. The trades will ease Tuesday night and Wednesday, with drier trade wind weather moving back in. A shift to a land and sea breeze pattern is expected Wednesday night, with this pattern lingering into next weekend. Light winds will keep showers near the coast at night and over interior and leeward areas each afternoon. A return of light to moderate trades and windward focused showers is possible by the end of the weekend.
Discussion
Currently at the surface, a 1029 mb high is centered around 1000 miles north of Honolulu, and is driving moderate to breezy trade winds across the island chain early this morning. Infrared satellite imagery shows mostly clear to partly conditions, with a bit more cloud cover in some windward areas. Radar imagery shows isolated to scattered showers moving into windward portions of the islands, with mainly dry conditions in leeward locales. Main short term focus revolves around trade wind trends and rain chances.
A ridge of high pressure north of the islands will settle slowly east-southeastward during the next couple days, keeping breezy trade winds blowing across the state. A front passing by north of the islands will ease the trades Wednesday with light and variable winds expected Thursday through Saturday with sea and land breezes common statewide. A new high building northwest of the islands could bring a return of light to moderate trades by the end of the weekend.
As for the remaining weather details, rather dry and stable trade wind weather will prevail today, with light showers mainly affecting windward slopes and coasts. A band of enhanced moisture associated with an old front will move through the islands late tonight and Tuesday, increasing showers in windward areas and sending a few more showers into leeward locales. Drier conditions should move back into the islands Tuesday night and Wednesday, with mainly windward showers expected. A land and sea breeze pattern will set up Wednesday night and continue through Saturday. No significant rainfall is expected during this time, with showers holding mainly near the coast each night and over interior areas during the afternoon hours. A return of the trades should focus showers back over windward areas by the end of the weekend.
Aviation
The high pressure ridge far north of the islands will weaken and drift closer to the islands over the next few days as a cold front approaches from the north. Breezy to locally windy trade winds will continue through this evening, then weaken starting on Tuesday. Scattered showers remain in the forecast for most areas through this evening favoring windward and mountain sections of each island. Shower trends will increase and become numerous after midnight as unstable clouds from an old cold front slowly drift through the islands on Tuesday morning.
AIRMET Tango remains in effect for moderate turbulence below 9000 feet, over and immediately southwest through northwest of mountains. This AIRMET will likely remain in effect through this evening due to breezy easterly trade winds.
Marine
Fresh to strong easterly trades will continue through Tuesday, then ease into the moderate category Tuesday night through Wednesday as a front passes to the north. This will allow the Small Craft Advisory to be scaled back to the waters around Maui County and the Big Island today. Guidance shows the tail-end of the aforementioned front drifting southward into the area through the second half of the week, which will lead to light winds with localized land and sea breezes near the coasts beginning Wednesday night into Thursday. Ridge nosing eastward trailing this boundary will lead to the background flow shifting out of northeast through the weekend.
Surf along south facing shores will steadily lower through Tuesday as the long-period south swell moves out. Another long- period background pulse due tonight will be enough to keep the surf from going flat Tuesday through midweek. Thereafter, a combo of small southeast and southerly energy moving through with background level surf anticipated through the rest of the week. For the long range, a gale moving through the Tasman Sea over the next couple of days could provide a small long-period south- southwest swell early next week, potentially arriving early next week.
Surf along east facing shores will remain up into Tuesday, then lower Wednesday through the second half of the week as the trades relax locally and upstream.
Surf along north facing shores will remain small through the first half of the week, then trend up through the second half. Guidance shows a broad gale setting up over the far northern Pacific near the Aleutians (east of the Date Line) around midweek with a large/broad fetch expanding southward Wednesday through Thursday with winds focused down the 335-350 degree directional band relative to the islands. This will drive a moderate medium-period north-northwest swell through the islands beginning late Thursday with a peak expected Friday night through the weekend. Heights may reach the advisory level for north facing shores as it peaks, which may be long-lived/broad peak with the system projected to stall south of Kodiak Friday through Saturday.
HFO Watches/Warnings/Advisories
Small Craft Advisory until 6 PM HST this evening for Kaiwi Channel, Maui County Windward Waters, Maui County Leeward Waters.
Small Craft Advisory until 6 AM HST Wednesday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.
Data Courtesy of NOAA.gov