West Side

Today: Mostly sunny. Breezy. Isolated showers in the morning. Highs 76 to 88. East winds 10 to 25 mph decreasing to up to 25 mph in the afternoon. Gusts up to 45 mph. Chance of rain 20 percent.

Tonight: Breezy. Partly cloudy with isolated showers. Lows 65 to 75. East winds up to 25 mph increasing to 10 to 25 mph after midnight. Gusts up to 45 mph. Chance of rain 20 percent.

Monday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 76 to 89. East winds 10 to 25 mph with gusts to 45 mph. Chance of rain 20 percent.

South Side

Today: Sunny and windy. Highs 78 to 90. Northeast winds up to 30 mph.

Tonight: Mostly clear. Breezy. Lows 68 to 73. Northeast winds up to 25 mph. Gusts up to 45 mph in the evening.

Monday: Sunny and windy. Highs 78 to 90. Northeast winds 10 to 30 mph.

North Shore

Today: Partly sunny in the morning then becoming mostly sunny. Breezy. Scattered showers. Highs 80 to 87 near the shore to around 66 near 5000 feet. East winds up to 25 mph with gusts to 45 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 69 to 74 near the shore to around 54 near 5000 feet. East winds up to 25 mph increasing to 10 to 25 mph after midnight. Gusts up to 45 mph. Chance of rain 50 percent.

Monday: Breezy. Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 81 to 87 near the shore to around 66 near 5000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Central Maui

Today: Mostly sunny. Windy. Highs 81 to 89. East winds 10 to 30 mph.

Tonight: Partly cloudy. Windy. Isolated showers after midnight. Lows 68 to 73. East winds 10 to 30 mph shifting to the northeast 10 to 20 mph after midnight. Chance of rain 20 percent.

Monday: Mostly sunny. Windy. Highs 81 to 89. East winds 10 to 30 mph.

Upcountry

Today: Breezy. Mostly sunny with isolated showers. Highs 54 to 71. East winds up to 25 mph. Chance of rain 20 percent.

Tonight: Breezy. Partly cloudy with isolated showers. Lows around 47 at the visitor center to around 45 at the summit. East winds 10 to 25 mph. Chance of rain 20 percent.

Monday: Mostly sunny. Breezy. Isolated showers in the morning. Highs 55 to 72. East winds 10 to 25 mph. Chance of rain 20 percent.

East Maui

Today: Partly sunny in the morning then becoming mostly sunny. Breezy. Scattered showers. Highs 80 to 87 near the shore to around 66 near 5000 feet. East winds up to 25 mph with gusts to 45 mph. Chance of rain 50 percent.

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 69 to 74 near the shore to around 54 near 5000 feet. East winds up to 25 mph increasing to 10 to 25 mph after midnight. Gusts up to 45 mph. Chance of rain 50 percent.

Monday: Breezy. Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 81 to 87 near the shore to around 66 near 5000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Lanai City

Today: Mostly sunny. Breezy. Isolated showers in the afternoon. Highs 72 to 82. Northeast winds up to 25 mph shifting to the east 10 to 20 mph in the afternoon. Gusts up to 45 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Breezy. Lows 60 to 68. Northeast winds 10 to 25 mph.

Monday: Mostly sunny. Breezy. Isolated showers in the afternoon. Highs 71 to 81. Northeast winds 15 to 25 mph. Chance of rain 20 percent.

Kaunakakai

Today: Mostly sunny. Breezy. Highs 71 to 89. East winds up to 25 mph increasing to 10 to 25 mph in the afternoon. Gusts up to 45 mph.

Tonight: Partly cloudy. Breezy. Lows 59 to 74. East winds 10 to 25 mph with gusts to 45 mph.

Monday: Mostly sunny. Windy. Highs 71 to 89. East winds 15 to 30 mph.

Detailed Forecast

Synopsis

A strong high pressure ridge anchored in place north of Hawaii will produce a stable and breezy to windy trade wind weather through Monday. Wind speeds will decrease slightly on Tuesday into moderate to breezy range. Brief passing showers will favor windward and mountain slopes, with late afternoon to evening showers along the Kona slopes of the Big Island, other leeward areas will be mostly dry.

Discussion

The satellite picture this morning continues to show fairly stable stratocumulus clouds riding into the windward mountain slopes of each island on the easterly trade winds. Upper air balloon soundings over the past 24 hours at Lihue and Hilo are observing temperature inversion heights in the 6,000 to 7,000 foot range. This means that brief passing showers as shown on local doppler radar will continue mainly over windward and mountain areas.
The strong ridge north of the state will build in over the islands today, increasing trade wind speeds into low level Wind Advisory thresholds for windier areas of Maui and Hawaii Counties. A Wind Advisory was issued this morning for 20 to 30 MPH wind speeds with gusts up to 50 MPH at times lasting through Monday afternoon. Fairly dry conditions with lower humidity levels coupled with these stronger winds will produce elevated fire weather conditions over leeward areas during the late morning to afternoon hours. Wind speeds will decrease slightly into the moderate to breezy range from Tuesday onward. Weather conditions into Wednesday continue to show a dry and breezy summer time conditions through much of the week. In the medium to long range weather outlook, operational models and model blends continue to show a slight increase in low level moisture and possibly a modest increase in shower activity from Wednesday night onward.

Aviation

A strong high pressure ridge north of the Hawaiian Islands will maintain fairly stable conditions and breezy to windy easterly trade winds through Monday. Passing showers will favor windward and mountain areas in the overnight to early morning hours, bringing the potential for brief MVFR conditions. Otherwise, VFR conditions will prevail.
AIRMET Tango remains in effect for moderate low-level turbulence over and downwind of island terrain. This AIRMET will likely persist as strong trade winds remain in the forecast.

Marine

High pressure will remain far north of area for the next several days, which will support fresh to strong trade winds across the islands. The Small Craft Advisory remains in effect for all Hawaiian coastal waters until 6 PM HST Monday, but this will likely need to be extended for some zones as gusty trades persist into early next week. The aforementioned surface high will move eastward and weaken slightly during the latter half of the week, but winds are likely to remain locally breezy in the typical windier channels and waters throughout much of the next seven days.
Surf along all shores will remain mostly unchanged through the rest of the weekend, though south shore surf is expected to slowly decline as a south swell fades over the next several days. The next small, medium- to long-period south swell is expected to arrive late Tuesday through Wednesday. This swell may boost south- facing shore surf heights to near summertime averages as it peaks on Wednesday. It will then decline through the rest of next week.
Surf along east-facing shores will be rough and choppy in response to the gusty easterly trade winds.

Fire weather

Breezy, gusty, and rather dry conditions will continue for the next few days. Minimum relative humidity at lower leeward elevations will likely fall at or below 45 percent each afternoon. Temperature inversion heights will drop as low as 5,000 feet. This will result in near critical fire weather conditions over dry leeward areas at times, though no headlines (watches or warnings) will be issued since the Keetch Byram Drought Index will remain below the 600 threshold at Honolulu.

HFO Watches/Warnings/Advisories

Wind Advisory until 6 PM HST Monday for Lanai Mauka, Kahoolawe, Maui Windward West, Maui Leeward West, Kohala, Molokai, Lanai Windward, Lanai Leeward, Lanai South, Maui Central Valley North, Maui Central Valley South, Windward Haleakala, South Haleakala, Big Island South, Big Island Southeast, Big Island North.
Small Craft Advisory until 6 PM HST Monday for all Hawaiian waters.

Data Courtesy of NOAA.gov