Hilo

Tonight: Occasional showers. Lows 60 to 69 near the shore to 51 to 57 at 4000 feet. North winds up to 10 mph. Chance of rain near 100 percent.

Tuesday: Mostly cloudy. Occasional showers in the morning, then numerous showers in the afternoon. Highs around 79 near the shore to around 65 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 80 percent.

Tuesday Night: Cloudy. Numerous showers in the evening, then occasional showers after midnight. Lows 59 to 68 near the shore to 51 to 56 at 4000 feet. Northeast winds around 10 mph. Chance of rain 90 percent.

Kona

Tonight: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows around 72 near the shore to 49 to 54 near 5000 feet. Light winds. Chance of rain 50 percent.

Tuesday: Partly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 81 to 86 near the shore to around 66 near 5000 feet. Light winds. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows around 71 near the shore to around 51 near 5000 feet. Light winds. Chance of rain 50 percent.

Waimea

Tonight: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows 61 to 71 near the shore to 54 to 61 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Tuesday: Partly sunny with scattered showers. Highs around 79 near the shore to 68 to 75 near 3000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 60 to 70 near the shore to 53 to 61 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Kohala

Tonight: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows 61 to 71 near the shore to 54 to 61 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Tuesday: Partly sunny with scattered showers. Highs around 79 near the shore to 68 to 75 near 3000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 60 to 70 near the shore to 53 to 61 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

South Big Island

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Lows around 74 near the shore to around 55 near 5000 feet. Northeast winds up to 15 mph. Chance of rain 20 percent.

Tuesday: Partly sunny. Breezy. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 85 near the shore to around 65 near 5000 feet. East winds up to 20 mph. Chance of rain 50 percent.

Tuesday Night: Partly cloudy. Isolated showers in the evening. Lows around 74 near the shore to around 54 near 5000 feet. Northeast winds 10 to 15 mph decreasing to up to 10 mph after midnight. Chance of rain 20 percent.

Puna

Tonight: Occasional showers. Lows 60 to 69 near the shore to 51 to 57 at 4000 feet. North winds up to 10 mph. Chance of rain near 100 percent.

Tuesday: Mostly cloudy. Occasional showers in the morning, then numerous showers in the afternoon. Highs around 79 near the shore to around 65 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 80 percent.

Tuesday Night: Cloudy. Numerous showers in the evening, then occasional showers after midnight. Lows 59 to 68 near the shore to 51 to 56 at 4000 feet. Northeast winds around 10 mph. Chance of rain 90 percent.

Waikoloa

Tonight: Mostly cloudy with isolated showers in the evening, then partly cloudy after midnight. Lows around 72 near the shore to around 53 above 4000 feet. Southeast winds up to 15 mph. Chance of rain 20 percent.

Tuesday: Partly sunny with isolated showers in the morning, then mostly sunny with scattered showers in the afternoon. Highs around 84 near the shore to 65 to 70 above 4000 feet. North winds up to 15 mph. Chance of rain 50 percent.

Tuesday Night: Partly cloudy with isolated showers. Lows around 72 near the shore to 50 to 55 above 4000 feet. Northeast winds up to 10 mph. Chance of rain 20 percent.

Detailed Forecast

Synopsis

Moderate easterly trade winds are expected to continue throughout the week. An upper level trough approaching the islands will deepen into an upper low near Kauai by Tuesday. This upper disturbance will pass by the islands, then linger northeast of the state throughout the week. This will result in increased clouds and showers across the region through the week. Shower activity will favor windward mountain areas in the overnight to early morning hours, with brief periods of showers drifting into leeward areas. Locations sheltered from the moderate easterly trade winds could also see increased clouds and a few showers during the afternoons.

Short term update

An upper level trough moving into the Hawaii region from the west shows up clearly on the water vapor satellite imagery channel. This trough will deepen into a weak upper low and slowly drift eastward across the region into Wednesday. Expect deeper cloud heights under a weaker/higher subsidence temperature inversion, yielding enhanced shower activity across the state. This wet easterly trade wind pattern continues under the influence of upper level troughing lasting into the weekend. The highest chances for shower activity will favor the windward mountain slopes in the overnight to early morning hours. Sea breeze and trade wind convergence bands will develop in the afternoon hours with brief showers affecting western island slopes during this time period.
The current forecast grids look good, no evening updates.

Previous discussion

Issued at 349 PM HST Mon Apr 27 2026 This afternoon, GOES water vapor imagery shows a deepening trough aloft northwest of the main Hawaiian Islands. Meanwhile, high pressure at the surface centered far northeast of the main state is supporting moderate easterly trade winds across the region. Latest radar and satellite imagery shows scattered showers along primarily windward and mauka areas, though some sheltered leeward and interior locations have experienced increases in clouds and showers this afternoon as well due to localized sea breezes.
The upper level trough northwest of the islands will approach the state over the next 24 hours. As it approaches, this trough is forecast to develop into a weak closed low aloft near Kauai by Tuesday. Further destabilization will occur as temperature inversion heights rise and clouds heights deepen. Therefore, expect enhanced trade wind shower activity throughout this period.
The developing low aloft will drift eastward on Tuesday, but then is expected to linger northeast of the state for several days thereafter. With this upper disturbance lingering nearby, a continued wet trade wind weather pattern will continue for much of the rest of the week. These showers will typically favor windward and mountain slopes, especially during the overnight through early morning hours. Trades will maintain at moderate speeds throughout the week, so sheltered leeward areas could also see increases in afternoon clouds and a few showers as localized sea breezes develop each day.

Aviation

Moderate to locally breezy trade winds will continue during the next couple of days. A few briefly heavy showers can be expected over the next 24 hours or so as an upper level trough moves across the region. AIRMET Sierra is currently in effect for windward Oahu due to degraded cigs under showers, however this may improve during the day tomorrow. Borderline conditions for mountain obscuration may be observed across other islands through the night as well.

Marine

Issued at 349 PM HST Mon Apr 27 2026 Moderate to fresh east-northeasterly trades will continue through Tuesday, then strengthen Tuesday night or Wednesday as a weak trough currently traversing the main Hawaiian islands shifts to the west and a ridge builds north of the state. This will likely correspond to Small Craft Advisory winds across the typically windier waters surrounding Maui County and the Big Island beginning by Wednesday.
Surf along exposed north- and west-facing shores eases tonight as a northwest swell fades. However, a small bump in surf is expected through the day on Tuesday with the arrival of a small northwest swell. An upward trend is expected during the second half of the week as another northwest swell arrives. Looking further ahead, a storm-force low east of Japan will send a moderate, longer-period northwest swell toward the islands for Friday and Saturday, with surf heights potentially approaching advisory levels along exposed north and west facing shores.
Surf along south-facing shores will remain small through much of the week, with mainly background south to southwest swell expected. Another south-southwest pulse may arrive by this weekend from recent activity within our swell window east of New Zealand, providing a small increase in surf.
Surf along east-facing shores will remain relatively small and choppy through midweek, with a slight rise possible later in the week as trades strengthen.

HFO Watches/Warnings/Advisories

None.

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Data Courtesy of NOAA.gov