Photo Credit: Sebastien Gabriel

West Kaua’i

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 85 to 90 near the shore to around 75 above 3000 feet. Northeast winds up to 10 mph shifting to the west in the afternoon. Chance of rain 50 percent.

Tonight: Partly cloudy. Isolated showers in the evening, then scattered showers after midnight. Lows around 70 near the shore to around 61 above 3000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Monday: Sunny with isolated showers. Highs around 88 near the shore to around 76 above 3000 feet. East winds up to 15 mph. Chance of rain 20 percent.

South Kaua’i

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 83 to 89. Northeast winds 10 to 15 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy with numerous showers. Lows around 72. Northeast winds 10 to 15 mph. Chance of rain 70 percent.

Monday: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 83 to 90. Northeast winds 10 to 15 mph. Chance of rain 40 percent.

Kaua’i Mountains

Today: Mostly cloudy with showers. Highs 74 to 83 in the valleys to around 67 above 4000 feet. East winds up to 10 mph. Chance of rain 90 percent.

Tonight: Frequent showers. Lows 64 to 69 in the valleys to around 59 above 4000 feet. East winds up to 10 mph. Chance of rain near 100 percent.

Monday: Breezy. Partly sunny with scattered showers. Highs 76 to 84 in the valleys to around 68 above 4000 feet. East winds up to 10 mph increasing to up to 20 mph in the afternoon. Chance of rain 50 percent.

North Kaua’i

Today: Partly sunny. Numerous showers in the morning, then scattered showers in the afternoon. Highs 77 to 87. East winds up to 15 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then frequent showers after midnight. Lows 65 to 73. Southeast winds up to 10 mph. Chance of rain 90 percent.

Monday: Mostly sunny with scattered showers. Highs 78 to 87. East winds up to 15 mph. Chance of rain 50 percent.

East Kaua’i

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 75 to 86. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 70 percent.

Tonight: Numerous showers in the evening, then frequent showers after midnight. Lows 65 to 76. Northeast winds around 10 mph. Chance of rain near 100 percent.

Monday: Partly sunny in the morning then becoming mostly sunny. Scattered showers. Highs 75 to 86. East winds 10 to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Moderate trades will focus low clouds and showers over windward and mauka areas through next week, especially overnight and during the early morning. Periodic high clouds will transit area skies.

Discussion

An inversion around 6.5kft at Lihue and Hilo on this morning's soundings are symptomatic of the typical, stable summertime pattern in place over the islands. Mid-level ridging over the Northeast Pacific will support moderate to locally breezy trades through the forecast period while the subtropical jet funnels periodic high clouds across area skies. The latest model analysis indicates a trough embedded in the trades and anchored around 700mb. Though subtle on satellite imagery, the western half of state is observing a slow but steady increase in shower coverage at press time. Similar to yesterday to yesterday morning, a few locally heavy showers noted. A building mid-level ridge will nudge the subtropical jet north of the area during the middle of next week. Consequently, the attendant upper- level low north of Kauai will shear back into the westerlies, the back edge modeled to sharpen as it swings through. This will be largely inconsequential, but may bring about a slight uptick in trade showers and mid/upper cloud cover during the latter half of next week. Mid-level subsidence works steadily downward during this time, bringing a further increase in mid- level stability from about Wednesday onward.

Aviation

A high pressure ridge far north of the Hawaii region will keep moderate trade winds blowing across the state through tonight. Expect periods of showers, mainly along north and east slopes of each island, with brief periods of MVFR conditions in the heaviest shower bands.
No AIRMETs in effect and none are expected.

Marine

A surface ridge far north of the state will maintain moderate trade winds this morning. The trade winds are expected to gradually strengthen later today and tonight as the surface ridge builds north of the state. Based on the latest forecast, the trade winds will likely reach the Small Craft Advisory (SCA) criteria over the typically windier waters adjacent to the islands of Maui County and the Big Island tonight. Therefore, a SCA is in effect from this evening through the afternoon of Tuesday July Fourth for these waters. This SCA will likely need to be extended beyond Tuesday, since the locally strong trade winds are expected to persist through mid-week.
No significant swells are expected through Friday. Small south and southeast swells will maintain small background surf along south facing shores. By Tuesday, some southwest swell energy may also be added to the mix, but surf will likely remain small along south facing shores through Friday. A new slightly larger southwest swell may boost surf heights along south facing shores next weekend. Elsewhere, the weak trade wind regime will likely keep surf small along east facing shores early this week. As the trade winds strengthen, expect choppy surf to gradually build to modest heights along east facing shores later this week.

HFO Watches/Warnings/Advisories

Small Craft Advisory from 6 PM this evening to 6 PM HST Tuesday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov