Hilo

Today: Scattered showers, mainly before 1pm. Mostly sunny, with a high near 83. Light and variable wind becoming east northeast 5 to 9 mph in the afternoon. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Tonight: Scattered showers, mainly after 7pm. Mostly cloudy, with a low around 66. East wind around 5 mph becoming light and variable. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday: Scattered showers. Partly sunny, with a high near 83. Calm wind becoming east 5 to 9 mph in the afternoon. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Kona

Today: Isolated showers after noon. Mostly sunny, with a high near 79. East wind 6 to 10 mph becoming west northwest in the morning. Chance of precipitation is 20%.

Tonight: Isolated showers. Partly cloudy, with a low around 65. Northwest wind 7 to 10 mph becoming east in the evening. Chance of precipitation is 20%.

Tuesday: Scattered showers after noon. Partly sunny, with a high near 79. East wind 5 to 7 mph becoming calm in the afternoon. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Waimea

Today: Isolated showers. Mostly sunny, with a high near 78. Breezy, with a northeast wind 11 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

Tonight: Scattered showers, mainly after midnight. Partly cloudy, with a low around 58. Breezy, with a northeast wind 11 to 16 mph, with gusts as high as 22 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday: Scattered showers. Partly sunny, with a high near 78. Breezy, with a northeast wind 10 to 16 mph, with gusts as high as 23 mph. Chance of precipitation is 40%. New precipitation amounts between a tenth and quarter of an inch possible.

Kohala

Today: Scattered showers, mainly before noon. Partly sunny, with a high near 64. East southeast wind 5 to 8 mph. Chance of precipitation is 30%.

Tonight: Scattered showers. Partly cloudy, with a low around 53. Breezy, with an east wind 6 to 16 mph, with gusts as high as 23 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday: Scattered showers. Partly sunny, with a high near 64. Breezy, with an east wind 13 to 20 mph, with gusts as high as 26 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

South Big Island

Today: Sunny, with a high near 84. Breezy, with an east northeast wind 18 to 21 mph, with gusts as high as 26 mph.

Tonight: Isolated showers after midnight. Partly cloudy, with a low around 74. Breezy, with an east northeast wind 17 to 20 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.

Tuesday: Isolated showers. Mostly sunny, with a high near 84. Breezy, with an east wind 16 to 21 mph, with gusts as high as 26 mph. Chance of precipitation is 20%.

Puna

Today: Scattered showers. Partly sunny, with a high near 82. Northwest wind 6 to 10 mph becoming east northeast in the morning. 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. East northeast wind 6 to 8 mph becoming west northwest after midnight. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday: Scattered showers. Partly sunny, with a high near 82. West northwest wind 5 to 11 mph becoming east northeast in the morning. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Waikoloa

Today: Isolated showers after noon. Mostly sunny, with a high near 84. Breezy, with an east northeast wind 5 to 15 mph becoming west in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 20%.

Tonight: Isolated showers before midnight. Partly cloudy, with a low around 66. Light and variable wind becoming east northeast 5 to 10 mph after midnight. Chance of precipitation is 20%.

Tuesday: Scattered showers after noon. Mostly sunny, with a high near 84. East northeast wind 5 to 10 mph becoming west northwest in the morning. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

Detailed Forecast

Synopsis

Light to moderate trades will hold in place through Tuesday, with localized sea and land breezes developing in the more sheltered leeward areas. Fairly dry conditions should prevail through today and tonight, with mainly a few windward showers. A slight increase in showers is expected Tuesday and Tuesday night as a band of moisture moves through. Trades will get a boost back to moderate levels Wednesday and Thursday, then become breezy Friday through Sunday. With the strengthening trades, we should see a more typical windward and mauka focused shower pattern resume, with a stray shower reaching leeward areas from time to time.

Discussion

Currently at the surface, a ridge of high pressure is located around 225 miles north of Kauai, and extends to a 1022 mb high to the distant northeast. Meanwhile, a nearly stationary front is located around 300 miles northwest of Garden Isle. The resulting gradient is producing light to moderate trade winds across the island chain early this morning, with land breezes present in some of the more sheltered leeward areas. Infrared satellite imagery shows clear to partly cloudy skies in most areas, with a bit more cloud cover over portions of Kauai and the Big Island. Radar imagery shows a few isolated to widely scattered showers mainly moving into windward areas, with mainly rain free conditions in leeward areas, aside from a few showers along the leeward Big Island coast. Main short term concerns revolve around rain chances and trade wind trends during the next few days.
The trade winds will trend upward ever so slightly during the next couple days, as the ridge of high pressure north of the islands lifts slowly northward and further away from the state. The trades will likely remain light enough during this time however, to allow for localized sea and land breezes to develop in the most sheltered leeward areas. High pressure building northeast of the state will strengthen the trades to moderate levels during the middle of the week, with breezy trades expected to overspread the islands Friday through Sunday.
As for the remaining weather details, rather dry conditions should persist statewide today and tonight, with perhaps an increase in showers over windward sections of Maui and the Big Island toward daybreak Tuesday as a new band of moisture approaches from the east. This band of moisture will shift eastward across the islands Tuesday and Tuesday night, bringing scattered showers to windward areas, as well as an increase in daytime heating driven showers over leeward areas. A more typical trade wind shower pattern appears to resume Wednesday through Sunday, with showers favoring windward and mauka areas mainly during the overnight and early morning hours, and a stray shower reaching leeward areas from time to time.

Aviation

A high pressure ridge continues to slowly build north of the Hawaiian Islands. Easterly trade winds will gradually increase in strength into the moderate to breezy range from Wednesday onward. Brief passing showers are possible with isolated MVFR conditions favoring windward and mountain slopes.
No AIRMETs are currently in effect or anticipated at this time.

Marine

The western end of a surface ridge located north of the islands is lifting slowly northward early this morning. This will continue to cause the pressure gradient to tighten across the state early this week, which will produce moderate trade winds through Tuesday. By mid-week, expect locally strong trade winds to return. As a result, Small Craft Advisory conditions will likely develop over the typically windier waters adjacent to the islands of Maui County and the Big Island from Wednesday through Friday.
Small south and southeast swells will produce near summertime average surf along south facing shores through early Tuesday. A new long-period south-southwest swell arriving late Tuesday will likely cause an increase in surf heights along south facing shores from Tuesday night through Wednesday. Note that our current forecast keeps surf heights below the High Surf Advisory threshold along south facing shores when this swell likely peaks on Wednesday. This south-southwest swell will gradually lower from Thursday through Friday. The forecast guidance continues to show a larger long-period south-southwest swell arriving next Sunday. This swell may result in a significant increase in surf heights along south facing shores during the Independence Holiday Weekend.
The current short-period northwest swell will gradually decrease through mid-week. The latest forecast guidance continues to show a new small northwest swell arriving Friday, which may produce a small bump in surf heights along most north and west facing shores of the smaller islands from late Friday into Saturday. The moderate trade winds will produce small surf along east facing shores during the next few days. As the trade winds gradually strengthen later this week, expect choppy surf to increase along east facing shores, especially as we head into the weekend.

HFO Watches/Warnings/Advisories

None.

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Data Courtesy of NOAA.gov