Photo Credit: James Grenz

Hilo

Today: Scattered showers. Partly sunny, with a high near 81. Light and variable wind becoming east 5 to 7 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers. Mostly cloudy, with a low around 64. Light and variable wind becoming west southwest around 5 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Sunday: Scattered showers. Partly sunny, with a high near 82. Light and variable wind becoming east 5 to 8 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Kona

Today: Isolated showers after noon. Mostly sunny, with a high near 83. Light and variable wind becoming west 5 to 9 mph. Chance of precipitation is 20%.

Tonight: Scattered showers. Mostly cloudy, with a low around 63. Light and variable wind. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Sunday: Scattered showers after noon. Increasing clouds, with a high near 83. Light and variable wind becoming west 5 to 8 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Waimea

Today: Scattered showers, mainly after noon. Mostly sunny, with a high near 75. Breezy, with a northeast wind 11 to 17 mph, with gusts as high as 24 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers, mainly before midnight. Partly cloudy, with a low around 50. North northeast wind 7 to 14 mph, with gusts as high as 18 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Sunday: Scattered showers, mainly after noon. Partly sunny, with a high near 75. Breezy, with a northeast wind 9 to 14 mph increasing to 17 to 22 mph in the morning. Winds could gust as high as 31 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Kohala

Today: Scattered showers. Partly sunny, with a high near 69. Breezy, with an east wind 10 to 18 mph, with gusts as high as 25 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Showers likely, mainly before midnight. Mostly cloudy, with a low around 41. Breezy, with an east wind 15 to 21 mph, with gusts as high as 29 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

Sunday: Scattered showers. Partly sunny, with a high near 69. Windy, with an east wind 21 to 29 mph, with gusts as high as 43 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

South Big Island

Today: Isolated showers. Mostly sunny, with a high near 83. Windy, with an east wind 22 to 24 mph, with gusts as high as 31 mph. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 72. Breezy, with an east northeast wind 20 to 22 mph, with gusts as high as 29 mph. Chance of precipitation is 20%.

Sunday: Scattered showers, mainly after noon. Mostly sunny, with a high near 84. Windy, with an east wind 20 to 23 mph, with gusts as high as 30 mph. Chance of precipitation is 30%.

Puna

Today: Scattered showers. Partly sunny, with a high near 79. Light and variable wind becoming east northeast 6 to 11 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers. Mostly cloudy, with a low around 61. Light and variable wind becoming west northwest around 5 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Sunday: Scattered showers. Partly sunny, with a high near 80. Light north wind becoming east northeast 8 to 13 mph in the afternoon. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch possible.

Waikoloa

Today: Sunny, with a high near 81. East wind 8 to 10 mph becoming north in the morning.

Tonight: Mostly clear, with a low around 62. East northeast wind 5 to 9 mph becoming light east southeast after midnight.

Sunday: Scattered showers after noon. Increasing clouds, with a high near 81. Light and variable wind becoming northeast 6 to 11 mph in the afternoon. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Detailed Forecast

Synopsis

Moderate trade winds will remain into next week. Clouds and showers will focus over windward and mountain areas with an occasional shower reaching leeward locations. Some brief heavier showers will remain possible over Kauai today.

Discussion

An upper level trough is maintaining some instability over the western end of the state with isolated heavier showers moving westward over the coastal waters southwest of Kauai. These showers could bring some brief downpours over Kauai today.
High pressure far northeast of the islands will maintain easterly trade winds through the forecast period. Wind speeds will drop to moderate levels Sunday and into next week as the high moves farther away to the east. Showers riding the trade winds will push into the windward slopes bringing periodic clouds and rainfall. Some of these showers will reach leeward locations of the smaller islands. Weak upper level troughiness will persist into next week favoring an elevated inversion and a slightly wetter variety of trade wind weather. For the leeward Big Island, afternoon sea breezes and heating will allow for clouds and sporadic showers before clearing through the overnight and early morning hours. Trade winds re-strengthen Wednesday and into the latter part of the week as the high builds southward toward the islands. Some increasing showers are possible late next week as another upper trough approaches the state.

Aviation

While winds have weakened a touch overnight, expect winds to pick back up today to moderate to locally breezy levels. AIRMET Tango remains in effect for low level mechanical turbulence to the lee of the mountains on all islands. Winds are expected to weaken a bit tonight as high pressure to the northeast moves away from the islands. As this happens, the AIRMET will likely be dropped tonight or tomorrow.
Clouds and showers are being carried in on the trade winds, and are at times producing MVFR conditions mainly over the north and east sides of the islands. Currently no AIRMETs are in effect for mountain obscuration or IFR conditions, and none are expected this morning.

Marine

With surface high pressure centered far NE of the area and a broad surface trough to the W of the islands, moderate to locally strong trade winds have veered just slightly S of E. A Small Craft Advisory (SCA) is posted for waters around Maui County and the Big Island through this afternoon. Although little significant change is expected through the weekend, a front passing far N of the area may lead to a marginal weakening of the wind Sunday. As the trough to the W eventually dissipates next week, the moderate to locally strong trade winds will back to the more typical ENE direction.
Surf along all shores will remain below High Surf Advisory levels through next week. A small NW swell is expected to arrive Sunday before slowly diminishing Monday through Wednesday. Small swells arriving from the southern hemisphere will bring only a little increase in surf heights along S facing shores this weekend, and will likely keep surf from going flat for most of next week. Trade winds will deliver relatively small, short-period waves to E facing shores.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST this evening for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Windward Waters, Big Island Leeward Waters, Big Island Southeast Waters.

Data Courtesy of NOAA.gov