Hilo

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 83 near the shore to 68 to 73 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 70 percent.

Tonight: Cloudy with showers. Lows 63 to 71 near the shore to around 57 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 90 percent.

Tuesday: Cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 79 to 84 near the shore to around 70 at 4000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Kona

Today: Mostly cloudy with scattered showers. Highs 81 to 86 near the shore to around 68 near 5000 feet. West winds up to 10 mph. Chance of rain 40 percent.

Tonight: Mostly cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 73 near the shore to 50 to 55 near 5000 feet. Light winds. Chance of rain 30 percent.

Tuesday: Mostly cloudy. Scattered showers in the afternoon. Highs around 86 near the shore to around 70 near 5000 feet. East winds up to 10 mph shifting to the west in the afternoon. Chance of rain 40 percent.

Waimea

Today: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 81 near the shore to 68 to 78 near 3000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows 63 to 71 near the shore to 55 to 62 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Tuesday: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 79 near the shore to 69 to 78 near 3000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

Kohala

Today: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 81 near the shore to 68 to 78 near 3000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

Tonight: Mostly cloudy. Numerous showers in the evening, then scattered showers after midnight. Lows 63 to 71 near the shore to 55 to 62 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Tuesday: Mostly cloudy. Breezy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 79 near the shore to 69 to 78 near 3000 feet. East winds 10 to 20 mph. Chance of rain 70 percent.

South Big Island

Today: Mostly sunny in the morning then becoming partly sunny. Breezy. Isolated showers. Highs around 85 near the shore to around 72 near 5000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Tonight: Mostly cloudy. Breezy. Scattered showers in the evening, then isolated showers after midnight. Lows around 73 near the shore to around 53 near 5000 feet. East winds 10 to 20 mph. Chance of rain 30 percent.

Tuesday: Breezy. Mostly sunny in the morning, then mostly cloudy with isolated showers in the afternoon. Highs around 86 near the shore to around 70 near 5000 feet. East winds 10 to 20 mph. Chance of rain 20 percent.

Puna

Today: Mostly cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs around 83 near the shore to 68 to 73 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 70 percent.

Tonight: Cloudy with showers. Lows 63 to 71 near the shore to around 57 at 4000 feet. Northeast winds up to 10 mph. Chance of rain 90 percent.

Tuesday: Cloudy. Numerous showers in the morning, then scattered showers in the afternoon. Highs 79 to 84 near the shore to around 70 at 4000 feet. East winds up to 10 mph. Chance of rain 70 percent.

Waikoloa

Today: Breezy. Partly sunny with isolated showers. Highs around 85 near the shore to 69 to 75 above 4000 feet. Northeast winds up to 20 mph. Chance of rain 20 percent.

Tonight: Partly cloudy with isolated showers in the evening, then mostly cloudy with scattered showers after midnight. Lows 71 to 76 near the shore to around 54 above 4000 feet. Northeast winds up to 10 mph. Chance of rain 50 percent.

Tuesday: Mostly sunny in the morning then becoming mostly cloudy. Highs 82 to 88 near the shore to 66 to 75 above 4000 feet. Northeast winds up to 15 mph shifting to the north in the afternoon.

Detailed Forecast

Synopsis

A high pressure ridge will remain locked in place north of the Hawaii region through the rest of this week. A weak upper low drifting over the state into Tuesday will help produce periods of showers mainly over the windward and mountain areas in the overnight to early morning hours. The ridge to the north will strengthen from Wednesday onward, producing breezy to locally windy trade winds into next weekend.

Discussion

Radar imagery this morning shows scattered to numerous showers developing over and upstream of windward mountain ranges. Satellite imagery shows a band of low level clouds upstream of each island, moving into the windward slopes. This cloud band and a weak upper level low shown on the water vapor satellite channel will likely spread periods of showers along the windward and mountain slopes through the early morning hours. The weak upper level low continues to lift trade wind inversion heights this morning to around 7,000 feet at both Lihue and Hilo upper air observation sites. Temperature inversion heights at this level will support continued periods of trade wind showers favoring the windward and mountain areas through early Tuesday morning. This shower activity will decrease slightly during the mid morning to afternoon hours.
A subtropical high pressure ridge north of the Hawaiian Islands will produce moderate to breezy trade winds lasting through Tuesday. A slight increase in the easterly trade winds into the breezy to locally windy range will start on Wednesday and continue into next weekend as the ridge north of the islands strengthens. A cloud band from the likely remnants of an old East Pacific front may roll through the islands by Saturday, enhancing shower activity a bit for next weekend.
Otherwise little changes are forecast in the day to day island weather pattern with just more typical trade wind weather continues through the end of this week.

Aviation

Breezy easterly trades will continue, with clouds and showers favoring windward and mauka locations. Periods of MVFR conditions will continue over these windward sections through the morning hours. Otherwise, VFR conditions will prevail.
AIRMET Sierra for tempo mountain obscuration is in effect for most windward areas. Conditions should improve by mid morning.

Marine

Surface high pressure will remain north-northeast of the area, then gradually strengthen during the second half of the week. As a result, the trades will become fresh to locally strong, with near-gale winds in the Alenuihaha Channel and waters south of the Big Island beginning Wednesday. The Small Craft Advisory (SCA), currently in effect for the normally windier areas around Maui County and the Big Island, will likely continue through the week, with an expansion to include the waters around Kauai and Oahu on Wednesday.
Surf along south facing shores will continue to slowly decline as the south swell fades today. For the rest of the week, expect only background small, medium to long period, south to southeast swell energy moving through the local waters.
North shore surf is expected to be small through the week, coming from small, mainly medium-period, northwest swells. Surf along east shores will become increasingly rough and choppy from Wednesday onward as the trade winds strengthen across the state.

HFO Watches/Warnings/Advisories

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

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