Photo Credit: Brittney Cruz

West Side

Today: Sunny, with a high near 89. East northeast wind 5 to 7 mph becoming west in the morning.

Tonight: Mostly clear, with a low around 71. Light and variable wind becoming east northeast 5 to 10 mph in the evening.

Wednesday: Sunny, with a high near 88. East northeast wind 8 to 13 mph becoming light and variable in the afternoon.

South Side

Today: Mostly sunny, with a high near 90. Calm wind becoming west southwest around 6 mph in the afternoon.

Tonight: Mostly clear, with a low around 70. Northwest wind around 5 mph becoming calm.

Wednesday: Isolated showers after noon. Mostly sunny, with a high near 89. Light and variable wind becoming east northeast 5 to 9 mph in the afternoon. Chance of precipitation is 20%.

North Shore

Today: Sunny, with a high near 89. Breezy, with an east northeast wind 8 to 13 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 28 mph.

Tonight: Partly cloudy, with a low around 71. Breezy, with an east northeast wind 14 to 20 mph, with gusts as high as 28 mph.

Wednesday: Mostly sunny, with a high near 88. Breezy, with an east northeast wind 13 to 21 mph, with gusts as high as 29 mph.

Central Maui

Today: Sunny, with a high near 89. Breezy, with a north northeast wind 6 to 11 mph increasing to 13 to 18 mph in the afternoon. Winds could gust as high as 26 mph.

Tonight: Mostly clear, with a low around 69. Breezy, with a north northeast wind 11 to 16 mph, with gusts as high as 22 mph.

Wednesday: Mostly sunny, with a high near 88. Windy, with a north northeast wind 10 to 15 mph increasing to 18 to 23 mph in the afternoon. Winds could gust as high as 32 mph.

Upcountry

Today: Mostly sunny, with a high near 75. Calm wind becoming west 5 to 9 mph in the morning.

Tonight: Partly cloudy, with a low around 58. West wind around 6 mph becoming calm.

Wednesday: Mostly sunny, with a high near 74. Light and variable wind becoming east northeast 8 to 13 mph in the afternoon.

East Maui

Today: Isolated showers. Mostly sunny, with a high near 83. Southeast wind 7 to 9 mph. Chance of precipitation is 20%.

Tonight: Scattered showers, mainly after 7pm. Mostly cloudy, with a low around 68. East northeast wind 6 to 8 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Wednesday: Scattered showers. Partly sunny, with a high near 82. East wind around 8 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Lanai City

Today: Isolated showers after noon. Mostly sunny, with a high near 77. Breezy, with a northeast wind 6 to 16 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.

Tonight: Mostly clear, with a low around 64. Breezy, with a northeast wind 13 to 16 mph, with gusts as high as 22 mph.

Wednesday: Mostly sunny, with a high near 77. Breezy, with a northeast wind 13 to 17 mph, with gusts as high as 24 mph.

Kaunakakai

Today: Sunny, with a high near 87. Calm wind becoming east northeast 5 to 8 mph in the afternoon.

Tonight: Mostly clear, with a low around 71. East northeast wind 7 to 9 mph.

Wednesday: Sunny, with a high near 88. Breezy, with an east northeast wind 8 to 17 mph, with gusts as high as 23 mph.

Detailed Forecast

Synopsis

Trade winds will return today, reaching and holding at moderate levels tonight through early next week. Rather dry conditions will prevail through Wednesday night, with showers mainly confined to windward and mauka areas. The remnants of an old front will likely bring a notable increase in showers to Kauai and possibly Oahu Thursday into Friday. A more typical trade wind pattern is then expected Saturday through early next week, with showers favoring windward and mauka areas, mainly at night and during the early morning hours.

Discussion

Currently at the surface, a weak front is nearly stationary around 250 miles northwest of Kauai. Meanwhile, a 1025 mb high is centered 1600 miles northeast of Honolulu, with a ridge axis extending southwestward through to near the Garden Isle. The resulting gradient is producing light and variable winds over the western islands, with light to moderate trades over the eastern end of the state. Infrared satellite imagery shows clear to partly cloudy conditions in most areas, with a bit more cloud cover over the Big Island and windward Maui. Radar imagery shows a few light trade showers moving into windward sections of Maui and the Big Island, as well as along the leeward Big Island coast. Elsewhere, rain free conditions prevail. Main short term concern revolves around old frontal remnants sinking southward into the western islands Thursday into Friday.
The front northwest of the state will gradually dissipate during the next couple days, as high pressure becomes more dominant north of the state. This will allow trade winds to return from east to west across the island chain today, strengthening to moderate levels statewide by late this afternoon. High pressure will then strengthen as it moves eastward and eventually northeastward Wednesday through early next week, keeping moderate trade winds in place through the period with only minor fluctuations in strength.
As for the remaining weather details, dry and stable conditions will persist today, with a few showers possible near the coast this morning and over the island interiors this afternoon. We should see a transition over to a windward and mauka focused shower pattern tonight through Wednesday night, although it will be much drier than normal with the stable conditions in place. Both the GFS and ECMWF show a band of higher precipitable water values associated with the remnants of an old front sinking southward and into the western islands Thursday and Thursday night, which will likely bring a notable increase in trade wind showers to Kauai and possibly to Oahu, while Maui County and the Big Island remain in a dry trade wind regime. The remnants of the old front may linger over Kauai into the day Friday, before lifting northwest of the islands, putting the entire island chain in a dry trade wind pattern Friday night. A more typical trade wind regime should settle in Saturday through early next week, with showers focused mainly over windward and mauka areas, and a stray shower occasionally reaching leeward communities.

Aviation

Weak land breezes this morning will give way to building trade winds in the afternoon. Trade winds will carry ragged stratocumulus and isolated showers towards the windward slopes and coasts of all islands.
For Leeward Big Island, a weak eddy is detectable on infrared satellite just off the coast, and can be seen steering low topped stratus and stratocumulus back onto west facing slopes and coasts. Conditions are likely to persist for several more hours then rapidly dissipate shortly after sunrise. Later in the day, sea breezes and inland cumulus build-ups will return.
The air mass over the state remains very stable with a well defined inversion aloft between 05 kft and 07 kft. Shower activity will remain minimal, but isolated MVFR ceilings are to be expected. No AIRMETs are currently in effect or anticipated at this time.

Marine

A front washing out across the far northern offshore waters will allow for the return of trade winds that will fill in from east to west across the island chain today. Moderate trades the next couple of days will strengthen to more areawide fresh to locally strong magnitudes through the typically windier channels and bays as early as tonight or Wednesday morning.
The current northwest swell will top out through the day and peak surf along north and west facing shores. This swell will trend down to near flat from Wednesday though Friday. A series of small southerly swells will maintain slightly below normal surf along southern shorelines through mid week. South shore surf could trend up slightly late this week with the arrival of a couple of overlapping slightly larger, higher energy south-southwest swells. East facing shore surf will remain small through today. As trades strengthen through mid to late week over and upstream of the state, there may be a small bump in short period wind waves along eastern exposures.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov