Photo Credit: Braden Jarvis

West Kaua’i

Today: Mostly sunny. Isolated showers in the morning. Highs around 89 near the shore to around 77 above 3000 feet. Northeast winds up to 15 mph shifting to the south in the afternoon. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows around 71 near the shore to around 61 above 3000 feet. Northeast winds up to 15 mph. Chance of rain 20 percent.

Saturday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 90 near the shore to around 78 above 3000 feet. East winds up to 15 mph. Chance of rain 50 percent.

South Kaua’i

Today: Mostly sunny with isolated showers. Highs 83 to 90. Northeast winds 10 to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 73. Northeast winds 10 to 15 mph. Chance of rain 30 percent.

Saturday: Partly sunny with scattered showers. Highs 83 to 90. East winds 10 to 15 mph. Chance of rain 50 percent.

Kaua’i Mountains

Today: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 75 to 85 in the valleys to around 68 above 4000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers. Lows 64 to 71 in the valleys to around 58 above 4000 feet. East winds up to 10 mph. Chance of rain 50 percent.

Saturday: Mostly cloudy. Showers likely in the morning, then scattered showers in the afternoon. Highs 76 to 85 in the valleys to around 68 above 4000 feet. East winds up to 15 mph. Chance of rain 70 percent.

North Kaua’i

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 78 to 89. East winds up to 15 mph. Chance of rain 30 percent.

Tonight: Partly cloudy with scattered showers. Lows 65 to 74. Southeast winds up to 15 mph. Chance of rain 40 percent.

Saturday: Partly sunny with scattered showers. Highs 78 to 90. East winds up to 15 mph. Chance of rain 50 percent.

East Kaua’i

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 76 to 87. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 40 percent.

Tonight: Partly cloudy in the evening then becoming mostly cloudy. Scattered showers. Lows 65 to 76. Northeast winds up to 15 mph. Chance of rain 40 percent.

Saturday: Partly sunny with scattered showers. Highs 76 to 88. East winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Moderate trade winds will continue over the next few days, with breezy to locally windy trades returning by early next week. A dry and stable air mass across the region will help to limit windward and mauka showers over most islands today. A weak disturbance riding in on the trades will increase clouds and shower activity tonight into Saturday, with another weak disturbance moving across the islands next Tuesday. No significant rainfall is expected from either disturbance, but it should provide some beneficial rain for windward and mauka areas.

Discussion

A ridge of high pressure far north of the state will maintain moderate trade winds over the next several days. Meanwhile, radar and satellite imagery continue to show brief passing showers moving into windward areas of Maui, Molokai, and Oahu early this morning under partly to mostly cloudy skies. Overall, expect fair weather to continue through today with light showers over windward and mauka areas and mostly dry conditions across the leeward side.
The latest 12Z surface analysis from HFO shows a weak trough approximately 225 miles east of the Big Island. Guidance continues to show this trough moving across the state tonight into Saturday resulting in an uptick in windward and mauka showers, especially across Maui and the Big Island. The latest CIMSS MIMIC layer PWAT shows a blob of moisture around 1.6 inches east of the state this morning with modeled PWATs around 1.7 inches as the trough inches towards the Big Island. Periods of moderate showers are possible over windward Big Island and east Maui, with 1 to 2 inches of rain possible along the windward slopes of the Big Island on Saturday. Overall, just some showery weather is expected and it should not be a flooding concern.
Showers will generally increase over the western half of the state late Saturday into Sunday with scattered showers over windward areas. Leeward areas should see an increase in cloud cover, with some passing showers. Drier conditions return by late Sunday with breezy trades expected by Monday. Breezy to locally windy trade will then continue through much of the upcoming week as high pressure strengthens far northeast of the state.
Another disturbance is expected to move across the state on Tuesday, with model PWATs around 1.8 inches. This system should bring more widespread clouds and showers to windward and mauka areas of all islands. With the stronger trades in place expect some of these showers to spillover into leeward areas at times. Expect a return to more typical trade wind weather conditions behind the disturbance with strong trades continuing through the end of the upcoming week.

Aviation

Moderate to locally breezy trades will continue through the rest of the week and into the weekend. SHRA and low cigs will favor windward and mauka areas and could bring brief periods of MVFR. Otherwise, VFR should prevail.
No AIRMETs are currently in effect.

Marine

A high pressure system and weak trough far north of the Hawaiian Islands will keep moderate easterly trade winds blowing across the region into Sunday morning. Trade winds will begin to strengthen into the fresh to locally strong range starting Sunday afternoon as the high center, currently northwest of the state, drifts east and strengthens. Trade wind speeds will be strong enough to support Small Craft Advisory conditions over the windier waters and channels near Maui and the Big Island from Sunday evening through much of next week.
Slightly elevated surf along south facing shores will ease below average today. Background south swell energy pulses are forecast to continue with surf remaining below average. Small, choppy surf expected for east facing shores for the next several days due to to continued trade winds. Surf then becomes increasingly rough along east facing shores as locally strong trades return early next week.
Spring tides peak this weekend, and local tide gauges indicate water levels already running above guidance. Water levels are currently running at least 1 foot higher than the Mean Higher High Water (MHHW) threshold at Hilo, Kahului, and Honolulu and are approaching the 1 foot threshold at Lihue. Therefore, a Coastal Flood Statement remains in effect through the weekend.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov