Photo Credit: Tyler Rooke

West Side

Today: Sunny, with a high near 87. East northeast wind 8 to 13 mph becoming light and variable in the morning.

Tonight: Isolated showers. Partly cloudy, with a low around 68. Light east northeast wind increasing to 8 to 13 mph in the evening. Chance of precipitation is 20%.

Monday: Isolated showers before noon. Mostly sunny, with a high near 87. East northeast wind 5 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 20%.

South Side

Today: Isolated showers after noon. Mostly sunny, with a high near 88. Calm wind becoming south 5 to 7 mph in the afternoon. Chance of precipitation is 20%.

Tonight: Isolated showers before midnight. Mostly clear, with a low around 67. South wind 5 to 7 mph becoming calm. Chance of precipitation is 20%.

Monday: Isolated showers after noon. Mostly sunny, with a high near 88. North wind 5 to 9 mph becoming west southwest in the afternoon. Chance of precipitation is 20%.

North Shore

Today: Isolated showers before noon. Mostly sunny, with a high near 86. Windy, with an east northeast wind 15 to 24 mph, with gusts as high as 34 mph. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 68. Windy, with an east wind 15 to 23 mph, with gusts as high as 32 mph. Chance of precipitation is 20%.

Monday: Scattered showers, mainly before noon. Mostly sunny, with a high near 86. Breezy, with an east wind 15 to 22 mph, with gusts as high as 31 mph. Chance of precipitation is 30%.

Central Maui

Today: Isolated showers before noon. Mostly sunny, with a high near 87. Windy, with a northeast wind 11 to 16 mph increasing to 18 to 23 mph in the afternoon. Winds could gust as high as 32 mph. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 66. Breezy, with a northeast wind 8 to 18 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.

Monday: Isolated showers. Mostly sunny, with a high near 87. Breezy, with a northeast wind 8 to 13 mph increasing to 16 to 21 mph in the morning. Winds could gust as high as 29 mph. Chance of precipitation is 20%.

Upcountry

Today: Isolated showers after noon. Mostly sunny, with a high near 72. Light and variable wind becoming west southwest 6 to 11 mph in the morning. Chance of precipitation is 20%.

Tonight: Partly cloudy, with a low around 55. West southwest wind 6 to 11 mph becoming light and variable in the evening.

Monday: Mostly sunny, with a high near 72. Light and variable wind becoming east 5 to 10 mph in the morning.

East Maui

Today: Scattered showers. Partly sunny, with a high near 81. East wind 6 to 11 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers. Mostly cloudy, with a low around 65. East wind 8 to 10 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Monday: Scattered showers. Partly sunny, with a high near 81. East southeast wind 10 to 13 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 76. Breezy, with a northeast wind 15 to 20 mph decreasing to 9 to 14 mph in the afternoon. Winds could gust as high as 28 mph. Chance of precipitation is 20%.

Tonight: Partly cloudy, with a low around 64. North northeast wind 6 to 10 mph.

Monday: Isolated showers after noon. Mostly sunny, with a high near 76. Light and variable wind becoming northeast 6 to 11 mph in the afternoon. Chance of precipitation is 20%.

Kaunakakai

Today: Mostly sunny, with a high near 87. Breezy, with a light east northeast wind becoming east southeast 11 to 16 mph in the morning. Winds could gust as high as 22 mph.

Tonight: Mostly clear, with a low around 70. Breezy, with an east wind 6 to 16 mph, with gusts as high as 22 mph.

Monday: Mostly sunny, with a high near 87. Breezy, with an east wind 8 to 15 mph, with gusts as high as 21 mph.

Detailed Forecast

Synopsis

High pressure north of the state will keep moderate to breezy trade winds blowing through next weekend. A fairly typical trade wind shower regime is expected through the period. Showers will favor windward and mauka areas, particularly at night and during the early morning hours, with a stray shower reaching leeward communities from time to time.

Discussion

Currently at the surface, a broad 1036 mb high is centered around 1750 miles north of Honolulu, and is driving moderate trade winds across the island chain early this morning. Infrared satellite imagery shows a few areas of enhanced cloud cover moving through the islands bringing mostly cloudy conditions to much of Kauai and Oahu, as well as windward sections of Maui and the Big Island. Elsewhere, clear to partly cloudy conditions prevail. Radar imagery shows scattered showers moving into windward areas of most islands, with a few of these showers reaching leeward areas at times. Main short term concern revolves around trade wind trends during the next few days.
Strong high pressure will hold in place far to the north of the islands through Monday, then settle southward and closer to the state Tuesday through next weekend. Trade winds will prevail at moderate to locally breezy levels today, then ease to moderate levels tonight through Monday night. The trades are then expected to strengthen to breezy and locally windy levels Tuesday through Thursday, before easing once again into the moderate to locally breezy range Friday through next weekend.
As for the remaining weather details, a weak mid-level disturbance is expected to slowly slide westward across the islands today through Tuesday. This feature has already raised inversion heights around 2-3 kft in the past 12 hours across the eastern half of the state as evident by the increase in the low- level inversion height in latest 12Z PHTO sounding. This slight destabilization of the airmass has already brought an increase in trade wind showers early this morning, and this general trend toward a more typical trade wind regime is expected to continue today through Tuesday. In fact, not much change in the overall weather pattern is expected for the second half of the week, as bands of low clouds and showers continue to pass through the island chain. Overall, it looks like a beautiful next 7 days across the Aloha state, with showers favoring windward and mauka areas particularly at night and during the early morning hours, with a few showers spilling into leeward communities from time to time.

Aviation

Surface high pressure to the north of the state will bring moderate to occasionally breezy easterly trades through the forecast period. Thus, expect tempo moderate turbulence along the lee of mountain ranges. Isolated showers will affect mainly windward locations. This activity may bring brief periods of MVFR ceilings and visibility.
AIRMET TANGO remains in effect below 8000 feet for south thru southwest of mountain ranges due to tempo moderate turbulence.

Marine

A high far north of the area will maintain locally strong easterly trade winds over Hawaiian waters through the week. A Small Craft Advisory (SCA) is in effect for waters around the Big Island and Maui County through early tomorrow morning. The SCA will likely be extended.
A swell from the Tasman Sea west of New Zealand will maintain moderate surf along south facing shores today. Surf from this swell will fade tomorrow. Surf along south facing shores will remain small through the rest of the week. Surf along north facing shores will also remain small through the week. The locally strong trade winds will produce surf along east facing shores, but the fetch will be rather short. The wave periods will remain short and the wave heights will be limited.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 AM HST Monday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov