Photo Credit: James Grenz

Hilo

Today: Scattered showers. Partly sunny, with a high near 82. Light and variable wind becoming east northeast 5 to 7 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Showers likely. Mostly cloudy, with a low around 63. West southwest wind 3 to 5 mph. Chance of precipitation is 70%. New precipitation amounts of less than a tenth of an inch possible.

Monday: Showers likely, mainly before noon. Partly sunny, with a high near 82. Light and variable wind becoming east 5 to 10 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

Kona

Today: Scattered showers after 1pm. Mostly sunny, with a high near 83. West northwest wind 3 to 6 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers, mainly before 1am. Partly cloudy, with a low around 62. Light east northeast wind. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Monday: Isolated showers before 7am, then scattered showers after 1pm. Mostly sunny, with a high near 83. West southwest wind 3 to 6 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Waimea

Today: Scattered showers. Partly sunny, with a high near 76. Breezy, with a northeast wind 10 to 15 mph increasing to 16 to 21 mph in the morning. Winds could gust as high as 29 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 50. Breezy, with a northeast wind 13 to 20 mph, with gusts as high as 28 mph. Chance of precipitation is 40%. New precipitation amounts between a tenth and quarter of an inch possible.

Monday: Scattered showers. Partly sunny, with a high near 76. Breezy, with a northeast wind 14 to 22 mph, with gusts as high as 31 mph. Chance of precipitation is 40%. New precipitation amounts between a tenth and quarter of an inch possible.

Kohala

Today: Scattered showers. Partly sunny, with a high near 70. Windy, with an east wind 18 to 26 mph, with gusts as high as 38 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Showers likely. Mostly cloudy, with a low around 40. Windy, with an east wind 24 to 26 mph, with gusts as high as 38 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

Monday: Scattered showers. Partly sunny, with a high near 69. Windy, with an east wind 24 to 29 mph, with gusts as high as 41 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 84. Windy, with an east wind 21 to 23 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 72. Windy, with an east northeast wind 21 to 23 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.

Monday: Isolated showers. Mostly sunny, with a high near 84. Windy, with an east northeast wind 21 to 24 mph, with gusts as high as 31 mph. Chance of precipitation is 20%.

Puna

Today: Scattered showers. Partly sunny, with a high near 80. Light north wind becoming east northeast 6 to 11 mph in the afternoon. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Showers likely. Mostly cloudy, with a low around 58. North wind around 6 mph becoming west northwest in the evening. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.

Monday: Showers likely, mainly before noon. Mostly cloudy, with a high near 80. East northeast wind 5 to 13 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

Waikoloa

Today: Isolated showers after noon. Mostly sunny, with a high near 81. Northeast wind 5 to 13 mph. Chance of precipitation is 20%.

Tonight: Isolated showers before midnight. Mostly clear, with a low around 59. East southeast wind 7 to 13 mph. Chance of precipitation is 20%.

Monday: Isolated showers after noon. Sunny, with a high near 81. Breezy, with an east northeast wind 7 to 12 mph increasing to 13 to 18 mph in the morning. Winds could gust as high as 25 mph. Chance of precipitation is 20%.

Detailed Forecast

Synopsis

Moderate trade winds will remain through Wednesday with an increase to gusty winds expected for the second half of the week. Clouds and showers will focus over windward and mountain areas with an occasional shower reaching leeward locations.

Discussion

High pressure far northeast of the islands will maintain moderate easterly trade winds through the forecast period. Showers riding the trades 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 the week favoring an elevated inversion and a higher than normal cloud tops. 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

Moderate trades are expected today, with an uptick in winds tonight and tomorrow. Some clouds and showers are riding in on the trades, bringing some pockets of MVFR conditions to some windward slopes, particularly on the Big Island and Maui. Otherwise, VFR conditions are expected to prevail today. Some high clouds moving from the southwest to northeast are primarily located to the south of the Big Island, but at times are moving over the Big Island.
No AIRMETs are currently in effect. However as winds increase tonight and tomorrow, AIRMETs may be needed for mechanical turbulence to the lee of the mountains. Additionally, should the pockets of MVFR conditions mentioned above become more widespread, AIRMETs for mountain obscuration could be possible.

Marine

High pressure northeast of the state will keep moderate to locally strong trade winds in place during the next 7 days, with only minor fluctuations in strength. A Small Craft Advisory remains in effect for the Alenuihaha Channel through Monday, and will likely need to be expanded to include the other typically windier waters around Maui and the Big Island tonight or Monday.
An incoming northwest swell is expected to build this morning, peak this afternoon and tonight, then gradually lower Monday through Wednesday. This will give a boost to surf along north and west facing shores, before going nearly flat Thursday through next weekend. South shore surf will remain near the summertime average during the next 7 days as a series of overlapping south swells continue to move through the islands. With steady moderate to locally strong trade winds, east shore surf will remain near the climatological average through next weekend.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 6 PM HST Monday for Alenuihaha Channel.

Data Courtesy of NOAA.gov