Photo Credit: Tyler Rooke

West Side

Today: Sunny, with a high near 83. East northeast wind 5 to 13 mph becoming west southwest in the afternoon.

Tonight: Mostly clear, with a low around 68. South southeast wind 5 to 13 mph becoming east northeast in the evening.

Saturday: Isolated showers after noon. Sunny, with a high near 82. East wind 5 to 13 mph becoming southwest in the afternoon. Chance of precipitation is 20%.

South Side

Today: Isolated showers after 1pm. Increasing clouds, with a high near 83. North northeast wind 5 to 7 mph becoming west in the morning. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 66. Light and variable wind becoming northeast around 5 mph after midnight. Chance of precipitation is 20%.

Saturday: Scattered showers, mainly after 1pm. Mostly sunny, with a high near 82. Northeast wind around 6 mph becoming west northwest in the morning. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

North Shore

Today: Mostly sunny, with a high near 81. Breezy, with an east wind around 16 mph, with gusts as high as 22 mph.

Tonight: Isolated showers after midnight. Partly cloudy, with a low around 67. Breezy, with an east wind 11 to 15 mph, with gusts as high as 21 mph. Chance of precipitation is 20%.

Saturday: Isolated showers. Mostly sunny, with a high near 80. Breezy, with an east wind 14 to 18 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.

Central Maui

Today: Sunny, with a high near 81. Windy, with a northeast wind 11 to 16 mph increasing to 18 to 23 mph in the morning. Winds could gust as high as 32 mph.

Tonight: Mostly clear, with a low around 65. Breezy, with a north northeast wind 7 to 16 mph, with gusts as high as 22 mph.

Saturday: Isolated showers after noon. Sunny, with a high near 80. Breezy, with a northeast wind 9 to 14 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 28 mph. Chance of precipitation is 20%.

Upcountry

Today: Increasing clouds, with a high near 70. South wind 5 to 7 mph becoming light and variable in the afternoon.

Tonight: Partly cloudy, with a low around 55. Light and variable wind becoming south southeast 5 to 7 mph after midnight.

Saturday: Scattered showers after noon. Mostly sunny, with a high near 68. Light and variable wind becoming east 9 to 14 mph in the afternoon. Winds could gust as high as 18 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

East Maui

Today: Isolated showers after noon. Partly sunny, with a high near 79. Breezy, with an east southeast wind 11 to 15 mph, with gusts as high as 21 mph. Chance of precipitation is 20%.

Tonight: Scattered showers. Mostly cloudy, with a low around 63. East southeast wind 10 to 13 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Saturday: Scattered showers. Partly sunny, with a high near 78. Breezy, with an east southeast wind 13 to 16 mph, with gusts as high as 22 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. Increasing clouds, with a high near 75. East northeast wind around 6 mph becoming light and variable in the afternoon. Chance of precipitation is 20%.

Tonight: Isolated showers after midnight. Partly cloudy, with a low around 62. Light and variable wind becoming northeast around 6 mph after midnight. Chance of precipitation is 20%.

Saturday: Scattered showers, mainly after noon. Mostly sunny, with a high near 75. Northeast wind around 6 mph becoming west in the afternoon. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Kaunakakai

Today: Sunny, with a high near 80. Breezy, with an east wind 14 to 16 mph, with gusts as high as 22 mph.

Tonight: Mostly clear, with a low around 68. Breezy, with an east wind around 15 mph, with gusts as high as 21 mph.

Saturday: Sunny, with a high near 80. Breezy, with an east wind 14 to 21 mph, with gusts as high as 29 mph.

Detailed Forecast

Synopsis

Dry and stable trade wind weather will persist over the state today as a ridge holds north of the islands. Winds will begin to shift out of the east to southeast later today, and the air mass will moisten from the east, leading to a slight increase in showers. East to southeast winds will continue through the holiday weekend, and increasing moisture moving up from the southeast will lead to an uptick in showers. Unsettled weather may develop over the islands by the middle of next week.

Discussion

Deep layer ridging over the region will support the dry and stable conditions continuing today. Moderate to breezy trades will gradually shift out of the east-southeast direction later today through the weekend due to the proximity of the surface ridge. A modest increase in moisture moving up the island chain is expected as a surface trough and upper low move into the area from the southeast. The air mass will modify significantly with dewpoints surging into the mid to upper 60s for the eastern end of the state today, then to the smaller islands tonight into Saturday. This transition will result in increasing rainfall chances – beginning over windward Big Island later today, then to the windward areas of the smaller islands tonight through Saturday. Daytime sea breezes are expected over sheltered leeward areas, where isolated showers may briefly develop through the afternoon periods. Expect this general pattern to hold through Monday.
The previously mentioned upper-level low will pass southeast of the Big Island Saturday, then dive southward Sunday through Monday. Aside from strong winds and chances for winter weather on the high summits of the Big Island, this feature will have little direct impact.
Unsettled weather will be possible during the middle of next week. An approaching upper-level trough may destabilize the atmosphere and trigger increased showers, mainly for the western end of the state. Uncertainty remains high regarding the amount of moisture that could be pooled over the state and whether a front will make it to the islands. The GFS points toward unsettled weather for the western half of the island chain, while the ECMWF continues to hold the threat for heavy rainfall to the west of Kauai.

Aviation

Moderate to locally breezy trades will continue through the forecast period. Prevailing VFR is forecast for all locations with brief MVFR possible within heavier windward showers.
AIRMET Tango is in effect for Maui through the Big Island for low-level mechanical turbulence.

Marine

A combination of locally breezy winds and building combined seas prompted issuance of a Small Craft Advisory (SCA) for all Hawaiian waters through Saturday afternoon. Winds will veer this weekend as a front approaches the islands from the northwest. This front will reach the western coastal waters by mid week.
A large northwest swell is forecast to arrive this afternoon and pass down the island chain through Saturday. This swell will boost surf to High Surf Warning (HSW) levels along north and west- facing shorelines of the smaller islands. Surf should reach HSW heights early Saturday morning on Niihau, Kauai and Oahu, then exceed HSW levels along exposed shores of other islands down the chain through the day on Saturday. A smaller, reinforcing northwest swell Sunday will warrant either issuance of a High Surf Advisory (HSA) or continuation of the HSW. An HSA may need to be issued for west facing shores of the Big Island later. Surf will subside on Monday as these two swells pass. The next northwest swell may reach the islands and produce HSA level surf during the middle of next week.

HFO Watches/Warnings/Advisories

High Surf Warning until 6 PM HST Saturday for Niihau, Kauai Windward, Kauai Leeward, Waianae Coast, Oahu North Shore, Oahu Koolau, Molokai, Maui Windward West, Maui Central Valley, Windward Haleakala.
Wind Advisory until 6 AM HST Saturday for Big Island Summits.
Small Craft Advisory until 6 PM HST Saturday for all Hawaiian waters,

Data Courtesy of NOAA.gov