Weather Forecast

Hawaii County Weather Forecast for September 10, 2021

September 10, 2021, 7:16 AM HST
Listen to this Article
5 minutes
Loading Audio...
A
A
A

no slideshow

Photo Credit: James Grenz

Hilo

Today: Partly sunny with scattered showers. Highs 78 to 84 near the shore to 63 to 71 at 4000 feet. Northwest winds 10 to 15 mph shifting to the northeast in the afternoon. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers early in the evening, then occasional showers in the late evening and overnight. Lows 63 to 72 near the shore to 54 to 59 at 4000 feet. Light winds. Chance of rain 90 percent.

Saturday: Mostly cloudy. Showers likely in the morning, then scattered showers in the afternoon. Highs 77 to 83 near the shore to 64 to 70 at 4000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Kona

Today: Mostly sunny in the morning, then mostly cloudy with scattered showers in the afternoon. Highs 82 to 88 near the shore to around 67 near 5000 feet. Northeast winds up to 10 mph shifting to the west in the afternoon. Chance of rain 40 percent.

Tonight: Mostly cloudy early in the evening then becoming mostly clear. Scattered showers early in the evening, then isolated showers in the late evening and overnight. Lows 70 to 75 near the shore to 52 to 57 near 5000 feet. Northwest winds up to 10 mph in the evening becoming light. Chance of rain 40 percent.

ARTICLE CONTINUES BELOW AD

Saturday: Sunny in the morning, then mostly cloudy with scattered showers in the afternoon. Highs 83 to 88 near the shore to around 67 near 5000 feet. Southwest winds up to 10 mph. Chance of rain 50 percent.

Waimea

ARTICLE CONTINUES BELOW AD

Today: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 64 to 84. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tonight: Partly cloudy early in the evening then becoming mostly cloudy. Isolated showers early in the evening, then scattered showers in the late evening and overnight. Lows 63 to 70 near the shore to 56 to 63 near 3000 feet. East winds up to 10 mph in the evening becoming light. Chance of rain 50 percent.

Saturday: Partly sunny with scattered showers. Highs 64 to 84. East winds up to 15 mph. Chance of rain 50 percent.

Kohala

ARTICLE CONTINUES BELOW AD

Today: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 64 to 84. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tonight: Partly cloudy early in the evening then becoming mostly cloudy. Isolated showers early in the evening, then scattered showers in the late evening and overnight. Lows 63 to 70 near the shore to 56 to 63 near 3000 feet. East winds up to 10 mph in the evening becoming light. Chance of rain 50 percent.

Saturday: Partly sunny with scattered showers. Highs 64 to 84. East winds up to 15 mph. Chance of rain 50 percent.

South Big Island

Today: Mostly sunny in the morning, then mostly cloudy with scattered showers in the afternoon. Highs around 83 near the shore to around 65 near 5000 feet. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 40 percent.

Tonight: Mostly cloudy early in the evening then becoming mostly clear. Scattered showers early in the evening. Lows around 73 near the shore to around 53 near 5000 feet. Northeast winds up to 10 mph. Chance of rain 40 percent.

Saturday: Sunny in the morning, then mostly cloudy with isolated showers in the afternoon. Highs around 83 near the shore to around 65 near 5000 feet. East winds up to 15 mph. Chance of rain 20 percent.

Puna

Today: Partly sunny with scattered showers. Highs 78 to 84 near the shore to 63 to 71 at 4000 feet. Northwest winds 10 to 15 mph shifting to the northeast in the afternoon. Chance of rain 50 percent.

Tonight: Mostly cloudy. Scattered showers early in the evening, then occasional showers in the late evening and overnight. Lows 63 to 72 near the shore to 54 to 59 at 4000 feet. Light winds. Chance of rain 90 percent.

Saturday: Mostly cloudy. Showers likely in the morning, then scattered showers in the afternoon. Highs 77 to 83 near the shore to 64 to 70 at 4000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Waikoloa

Today: Mostly sunny in the morning, then partly sunny with scattered showers in the afternoon. Highs 83 to 89 near the shore to 66 to 73 above 4000 feet. East winds up to 15 mph shifting to the north in the afternoon. Chance of rain 40 percent.

Tonight: Partly cloudy. Scattered showers early in the evening. Lows around 73 near the shore to 50 to 56 above 4000 feet. East winds up to 15 mph in the evening becoming light. Chance of rain 50 percent.

Saturday: Sunny. Highs 83 to 89 near the shore to 66 to 72 above 4000 feet. Northwest winds up to 10 mph.

Detailed Forecast

Synopsis

Light to moderate trade winds today and Saturday will strengthen on Sunday, becoming locally breezy through at least Monday. Winds may diminish again on Tuesday and Wednesday. The trade winds will deliver a few clouds and showers to windward areas, mainly during nights and mornings. Today’s lighter winds will allow afternoon sea breezes to bring clouds and few showers to some leeward areas.

Discussion

Light to moderate NE trade winds prevail at the moment, due to a surface trough to the NE and surface highs centered to the NW and NE of the islands. With this synoptic set-up, winds are weakest over the E end of the chain, but have become fairly light over most of the state overnight, allowing land breezes to develop in many locations. Satellite and radar imagery highlight a slight overnight increase in showery low clouds moving into windward areas from the NE, and although it’s a little wetter than yesterday, coverage remains somewhat limited.
As the trough moves closer to the longitude of the islands this weekend, it will weaken and dissipate while the surface highs consolidate to the NE. The resulting tightening of the low-level pressure gradient is expected to support a trend toward locally breezy ENE trade winds for most areas Saturday night into Sunday, although a lingering weakness in the gradient may keep winds weaker near the Big Island.
A strong low-level subsidence inversion will keep the island atmosphere capped into next week, while an anticipated increase in low-level moisture arriving from the NE has led to a modest increase in shower coverage. With the lighter winds today, afternoon sea breezes may become sufficiently strong to drive some leeward clouds/showers, and potentially again tomorrow. Thereafter, guidance indicates a fairly typical trade wind weather regime into next week, with passing low clouds and showers occasionally delivering a few showers, mainly windward.
Declining trade winds and some instability are possible around the middle of next week as a low aloft passes N of the islands. The low may induce the development of yet another low-level trough that eases the local pressure gradient, while also bringing mid- and high- level clouds over the area. Model guidance is somewhat divergent, reducing forecast confidence.

Aviation

Light to locally moderate trade winds will persist through twenty- four hours and beyond. Bands of light showers will impact mainly north and northeast facing slopes and coasts. Brief periods of MVFR CIG or VIS are to expected in passing showers. Otherwise VFR conditions will prevail all areas.
Light sea breezes across Leeward Big Island will promote convective development over south and west facing slopes this afternoon and evening. However, a strong inversion aloft around 09 kft will limit vertical development, so few associated showers are expected.
AIRMET Tango remains in effect for high level turbulence statewide. Conditions are expected to end later today as the upper level jet shifts well east of the islands.

Marine

An upper level disturbance northeast of the islands will wobble around north of the state into next week keeping periods of wet weather in the forecast. The high pressure ridge will remain strong enough to produce light to moderate trade winds today, trending up into the moderate to locally fresh range from Saturday into the first half of next week.
A series of small long period southeast to south swells will continue to keep surf heights along south facing shores just below seasonal average heights into early next week. Another increase in the south swell action may arrive by late Wednesday.
Small trade wind surf will continue along east facing shores this week.
Smaller surf remains in the forecast for north and west facing shores. A small northeast trade swell wrap and a small, medium period, north-northwest swell may keep surf heights just above flat conditions into early next week.

HFO Watches/Warnings/Advisories

None.

Big Island Now Weather is brought to you by Blue Hawaiian Helicopters.

Check out their Big Island Helicopter Tours today!

Data Courtesy of NOAA.gov

Comments

This comments section is a public community forum for the purpose of free expression. Although Big Island Now encourages respectful communication only, some content may be considered offensive. Please view at your own discretion. View Comments

Newsletters

Get a quick summary of what’s happening on the Big Island with our daily & weekly email of news highlights.