West Side

Today: Mostly sunny with isolated showers. Highs 79 to 85. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers. Lows 69 to 78. East winds up to 15 mph in the evening becoming light. Chance of rain 20 percent.

Wednesday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 80 to 85. Southeast winds up to 15 mph. Chance of rain 40 percent.

South Side

Today: Sunny. Highs around 87. North winds up to 15 mph increasing to 10 to 15 mph in the afternoon.

Tonight: Partly cloudy. Isolated showers in the evening. Lows 69 to 77. North winds up to 15 mph. Chance of rain 20 percent.

Wednesday: Sunny. Isolated showers in the afternoon. Highs around 87. Northwest winds up to 15 mph. Chance of rain 20 percent.

North Shore

Today: Partly sunny with scattered showers. Highs around 82 near the shore to around 65 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then occasional showers after midnight. Lows around 72 near the shore to around 55 near 5000 feet. East winds up to 15 mph. Chance of rain 90 percent.

Wednesday: Partly sunny with scattered showers. Highs around 82 near the shore to around 66 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Central Maui

Today: Mostly sunny. Scattered showers in the morning, then isolated showers in the afternoon. Highs 80 to 88. Northeast winds up to 15 mph increasing to 10 to 15 mph in the afternoon. Chance of rain 30 percent.

Tonight: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows 69 to 75. Northeast winds up to 15 mph. Chance of rain 50 percent.

Wednesday: Mostly sunny with isolated showers. Highs 81 to 88. Northeast winds up to 15 mph. Chance of rain 20 percent.

Upcountry

Today: Mostly sunny in the morning then becoming partly sunny. Scattered showers. Highs around 62 at the visitor center to around 66 at the summit. East winds up to 10 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows around 51 at the visitor center to around 43 at the summit. East winds up to 10 mph. Chance of rain 50 percent.

Wednesday: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs around 62 at the visitor center to around 66 at the summit. East winds up to 15 mph. Chance of rain 50 percent.

East Maui

Today: Partly sunny with scattered showers. Highs around 82 near the shore to around 65 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then occasional showers after midnight. Lows around 72 near the shore to around 55 near 5000 feet. East winds up to 15 mph. Chance of rain 90 percent.

Wednesday: Partly sunny with scattered showers. Highs around 82 near the shore to around 66 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Lanai City

Today: Mostly sunny. Isolated showers in the morning, then scattered showers in the afternoon. Highs 72 to 80. Northeast winds up to 15 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy with scattered showers in the evening, then partly cloudy with isolated showers after midnight. Lows 66 to 71. Northeast winds up to 15 mph in the evening becoming light. Chance of rain 50 percent.

Wednesday: Sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 72 to 81. Northeast winds up to 15 mph. Chance of rain 50 percent.

Kaunakakai

Today: Mostly sunny in the morning then becoming partly sunny. Scattered showers. Highs 69 to 88. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy in the evening then becoming partly cloudy. Scattered showers. Lows 60 to 75. East winds up to 15 mph. Chance of rain 50 percent.

Wednesday: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 71 to 89. East winds up to 15 mph. Chance of rain 50 percent.

Detailed Forecast

Synopsis

Locally breezy trade winds will weaken to moderate levels today and Wednesday, then strengthen Thursday into the weekend. Showers will continue to favor windward and mauka areas, with showers more common today and Wednesday compared to later in the week or this coming weekend.

Discussion

Radar and satellite show showers and clouds increasing as of 3 AM HST as an area of increasing moisture moves into the state. Winds continue to decrease in speed, and this trend is expected to continue through Wednesday.
A large surface high to the north will help keep trade winds blowing for the coming week, but wind speeds will decrease today through Wednesday before increasing again Thursday and remaining moderate into the weekend. Showers will increase today (as we are already seeing this morning), tonight, and Wednesday before drier air moves in and reduces showers from Thursday onward. As is typical for trade winds, the majority of showers will be windward and mauka.
Models have been consistently showing an increase in potential tropical systems in the central and eastern Pacific in the next couple of weeks, but so far no storms appear headed toward the state. However, with El Nino picking up steam and now forecast to reach record or near-record strength, now would be a great time to make sure you are prepared in case that changes.

Aviation

Trades will weaken during the day today, with intermittent showers expected to impact primarily windward sites through the forecast period. Downstream radar and satellite imagery suggest that a band of moisture may disproportionately impact windward Kauai and Oahu with showers today, with some spillover into leeward sites possible. Outside of those two areas, however, VFR is broadly anticipated.
No AIRMETS are currently in effect, however this may change should shower activity become widespread enough to promote mountain obscuration.

Marine

Trade winds will gradually ease today as the high pressure north of the islands lifts northeast and weakens. The Small Craft Advisory (SCA) has been cancelled as winds have dropped below criteria. These lighter trades should continue through Wednesday night, then may increase a bit Thursday and Friday as high pressure northeast of the islands drops a bit further south and tightens up the local pressure gradient.
The current small, long-period southwest swell will gradually decline through the middle of the week. A series of overlapping small south and southwest swell should produce some rideable surf through next weekend, with perhaps a more sizable south swell moving in early next week.
Surf along east-facing shores will steadily decline through Wednesday. Surf will then hold steady at slightly below seasonal averages along east facing shores through the weekend.
A series of small, long to medium period west to west-northwest swells generated by former Super Typhoon Bavi will be possible throughout the rest of the week. Otherwise, no significant north or northwest swells are expected, so surf along north-facing shores is expected to remain flat to tiny.
Peak monthly high tides combined with water levels that are running slightly higher than predicted will lead to minor flooding along the shoreline and in low-lying coastal areas. Coastal flooding is possible around the daily peak tide, which will be during the afternoon hours. A Coastal Flood Statement remains in effect through 6 PM this evening.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov