West Kaua’i

Today: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 81 near the shore to around 68 above 3000 feet. Light winds. Chance of rain 40 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Lows around 68 near the shore to around 59 above 3000 feet. Light winds. Chance of rain 20 percent.

Tuesday: Mostly cloudy with isolated showers. Highs around 80 near the shore to around 69 above 3000 feet. Light winds. Chance of rain 20 percent.

South Kaua’i

Today: Mostly cloudy. Isolated showers in the afternoon. Highs 76 to 82. Light winds. Chance of rain 20 percent.

Tonight: Mostly cloudy. Isolated showers in the evening. Lows around 68. Light winds. Chance of rain 20 percent.

Tuesday: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 75 to 82. Light winds. Chance of rain 40 percent.

Kaua’i Mountains

Today: Mostly cloudy. Isolated showers in the morning, then scattered showers in the afternoon. Highs 72 to 78 in the valleys to around 62 above 4000 feet. Southwest winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy. Scattered showers in the evening. Lows 61 to 67 in the valleys to around 57 above 4000 feet. West winds up to 10 mph. Chance of rain 50 percent.

Tuesday: Mostly cloudy with scattered showers. Highs 70 to 77 in the valleys to around 62 above 4000 feet. Light winds. Chance of rain 50 percent.

North Kaua’i

Today: Mostly cloudy. Scattered showers in the afternoon. Highs 71 to 80. Southwest winds up to 10 mph shifting to the west in the afternoon. Chance of rain 40 percent.

Tonight: Mostly cloudy. Scattered showers in the evening. Lows 61 to 70. Light winds. Chance of rain 40 percent.

Tuesday: Mostly cloudy with isolated showers. Highs 72 to 80. Light winds. Chance of rain 20 percent.

East Kaua’i

Today: Mostly cloudy. Isolated showers in the afternoon. Highs 71 to 81. Light winds. Chance of rain 20 percent.

Tonight: Mostly cloudy. Scattered showers in the evening. Lows 62 to 72. Light winds. Chance of rain 50 percent.

Tuesday: Mostly cloudy with scattered showers. Highs 70 to 80. Light winds. Chance of rain 50 percent.

Detailed Forecast

Synopsis

As the kona low exits to the north of the Hawaiian Islands, remnant bands of moderate showers continue over Leeward Big Island and Maui while conditions improve elsewhere. Toward the latter end of the week, another threat of heavy rain is anticipated as low pressure develops west of the islands.

Short term update

Issued at 959 AM HST Mon Mar 16 2026
Southerly kona winds continue across the region this morning, though speeds for lower elevations have dropped significantly versus what were observed yesterday. However, with that said, moisture embedded within the southerly flow can been seen on latest radar and satellite imagery making its way northeast. Most of the rain is occurring in or near the Alenuihaha Channel and the Big Island at this time. Regional satellite imagery shows convection developing upstream, southwest of the Big Island, where cloud tops are reaching up to around 45,000 feet. Pockets of heavy rain can be expected within this activity as it approaches the western districts of the Big Island late this morning into early afternoon. This scenario is also supported in the latest hi- res guidance and CAMs, the majority of which show some variation of an increase in showers and locally heavy rain over or near the Big Island and east Maui through the day today before tapering off this evening. Elsewhere, much lighter and more isolated to scattered showers are expected for the rest of the day.
Additionally, observations from the Big Island summits continue to show sustained winds in excess of 56 mph with gusts exceeding 66 mph. Therefore, the High Wind Warning will remain in effect for the summits of the Big Island and for Haleakala through the remainder of the day.

Prev discussion

Remnant bands of moderate showers continue to affect leeward Big Island and and portions of Maui County, and are expected to persist through at least tonight and possibly through Tuesday. However, recent observations indicate hourly rainfall rates remain below a tenth of an inch across both islands. In response to the reduced rainfall intensity and improved flooding thread, the Flash Flood Watch for Maui County and the Big Island has been cancelled with the issuance of this morning's forecast package.
Observations from the Maunakea Weather Center, along with model guidance indicating strong winds near the 600 mb level, suggest that high winds across the Big Island summits and Haleakala will persist beyond the previously scheduled 6 AM HST expiration time. As a result, the High Wind Warning has been extended through 6 PM HST this evening. Conditions will continue to be monitored and reevaluated with the next forecast cycle.
Confidence in the extended forecast beyond Monday remains somewhat limited as model guidance continues to evolve. Current solutions maintain an upper-level trough across the region, supporting a pattern of light and variable winds with periods of showers and the potential for isolated thunderstorms through much of the week. Toward the latter part of the week, model guidance diverges somewhat, with the GFS depicting a flatter and more progressive surface low while the ECMWF suggests a deeper and slower-moving system. The latest GFS run has trended closer to the ECMWF solution, increasing confidence that organized low pressure could develop over or near the island by late week. Given the uncertainty at this range, the forecast will continue to be refined in subsequent updates.

Aviation

Issued at 959 AM HST Mon Mar 16 2026
Showers continue to bring intermittent MVFR and isolated IFR to the area. Most areas will be VFR through today, even as showers increase in coverage and intensity over Maui and the Big Island this afternoon. Showers coverage will increase tonight over western islands, and remain over the eastern islands. Winds have decreased and turbulence does not appear to be a significant issue any longer.
AIRMET Sierra is in effect for mtn obsc for Maui, Lanai, and the Big Island. Conds in general will improve west to east and this AIRMET will be adjusted as necessary.

Marine

Issued at 328 AM HST Mon Mar 16 2026
Conditions over the marine area will continue to improve during the next couple of days, as the recent kona storm moves northeast and away from the area. Winds and seas have dropped below advisory levels early this morning, therefore the Small Craft Advisory (SCA) has been cancelled. The gradient in the wake of the storm will remain rather weak Tuesday and Wednesday, with light and variable winds prevailing over the waters. The pattern becomes more uncertain late in the week. A brief period of light to moderate trades will be possible Thursday as a weak ridge builds north of the state, followed by light to moderate southerly winds on Friday as a new storm system approaches from the west.
Surf along south facing shores will trend down lower today as south to southwesterly winds ease. A new long period south swell will then arrive late tonight and Tuesday, giving a nice and extended boost to south shore surf through late this week.
A moderate sized short-period west swell associated with the recent kona storm will affect north and west facing shores today, but surf will remain below advisory levels. As a result, the High Surf Advisory for west facing shores of the Big Island has been cancelled. The short-period west swell will lower tonight and Tuesday, while a new medium-period north-northwest swell fills in. This north-northwest swell could bring surf up close to advisory levels Tuesday night and Wednesday, with the swell then shifting more northerly and lowering below advisory levels Thursday into next weekend.
Surf along east facing shores will remain well below normal levels through late in the week as trade winds over and upstream of the islands appear to remain mostly disrupted.

HFO Watches/Warnings/Advisories

High Wind Warning until 6 PM HST this evening for Big Island Summits, Haleakala Summit.

Data Courtesy of NOAA.gov