As residents and visitors of Hawaii brace for the weekend, the islands are set to experience a mix of typical summertime weather patterns punctuated by an increase in showers, especially across windward and mauka regions. The forecast, spanning from the Big Island to Kaua’i, reveals a nuanced picture of shifting trade winds, moisture pockets, and varying rainfall chances that promise to keep the islands’ weather interesting through the weekend and into early next week.
On the Big Island, tonight’s weather (July 11, 2025) in Hilo is expected to be marked by occasional showers in the evening, escalating to numerous showers after midnight. Temperatures will range from 64 to 71 degrees Fahrenheit near the shore, cooling down to 51 to 58 degrees at 4,000 feet elevation. East winds will blow up to 10 mph before shifting southwest after midnight, with rain chances near 100 percent. Saturday will bring partly sunny skies with scattered showers, highs between 79 and 86 degrees near the shore, and 66 to 71 degrees at 4,000 feet, accompanied by southeast winds up to 10 mph and a 50 percent chance of rain. The night will again see occasional showers with similar temperatures and rain probabilities.
Kona’s forecast for tonight includes mostly cloudy skies with isolated showers in the evening, clearing after midnight. Lows will hover around 73 degrees near the shore and dip to 48 to 53 degrees near 5,000 feet, with light winds and a 20 percent chance of rain. Saturday’s weather will start mostly sunny but become partly sunny with scattered showers in the afternoon; highs will be around 86 degrees near the shore and 66 to 71 degrees near 5,000 feet. Winds will shift to the southwest at up to 10 mph, and the chance of rain will rise to 40 percent. Saturday night will be mostly cloudy with scattered showers, then partly cloudy with isolated showers after midnight, with lows around 73 degrees near the shore and about 52 degrees at 5,000 feet, and a 50 percent chance of rain.
Waimea and Kohala are forecasted to have similar weather patterns tonight through Saturday night, with partly cloudy skies and scattered showers, temperatures ranging from the low 60s to low 80s depending on elevation, and east winds between 10 and 15 mph. Rain chances will hover around 50 percent throughout this period.
South Big Island will experience partly cloudy and breezy conditions with isolated showers tonight and Saturday, lows around 74 degrees near the shore, highs near 86 degrees, and east winds between 10 and 20 mph. Rain chances remain relatively low at 20 percent.
The Puna district mirrors Hilo’s weather with occasional showers tonight escalating to numerous showers after midnight, lows between 64 and 71 degrees near the shore, and a near 100 percent chance of rain. Saturday sees partly sunny skies with scattered showers and a 50 percent chance of rain, while Saturday night returns to occasional showers with near 100 percent rain probability.
Waikoloa’s forecast includes mostly cloudy conditions with isolated showers tonight, clearing after midnight, lows around 73 degrees near the shore, and light east winds up to 10 mph. Saturday will be mostly sunny in the morning, becoming partly sunny with scattered showers in the afternoon, highs between 85 and 90 degrees near the shore, and southeast winds shifting to northwest during the afternoon. Rain chances are about 40 percent. Saturday night will be partly cloudy with isolated showers and a 20 percent chance of rain.
Kaua’i’s weather tells a similarly dynamic story. West Kaua’i tonight expects partly cloudy skies with scattered showers in the evening and isolated showers after midnight. Lows will be 68 to 74 degrees near the shore and around 61 degrees above 3,000 feet, with northeast winds at about 10 mph and a 50 percent chance of rain. Saturday will bring partly sunny to mostly sunny skies with scattered showers, highs between 85 and 91 degrees near the shore, and east winds around 10 mph.
South Kaua’i faces mostly cloudy conditions tonight with scattered showers, increasing to numerous showers after midnight. Lows will be around 72 degrees with northeast winds of 10 to 15 mph and a 70 percent chance of rain. Saturday will see partly sunny skies with numerous showers in the morning, then scattered showers in the afternoon, highs between 80 and 88 degrees, and a 70 percent chance of rain.
The Kaua’i Mountains are expected to be breezy and mostly cloudy with numerous showers tonight and Saturday, lows from 64 to 69 degrees in valleys and around 59 degrees above 4,000 feet, with east winds ranging from 10 to 20 mph. Rain chances sit at 70 percent tonight and Saturday, increasing to near 100 percent after midnight Saturday night.
North Kaua’i tonight will be mostly cloudy with numerous showers, lows between 65 and 74 degrees, and east winds of 10 to 15 mph. Saturday will be partly sunny with scattered showers and a 50 percent chance of rain. East Kaua’i’s forecast calls for mostly cloudy skies with numerous showers tonight and Saturday, lows from 64 to 76 degrees, and a 70 percent chance of rain.
Underlying these localized forecasts is a dominant 1033 mb high-pressure system situated far northeast of the state, which is maintaining moderate to locally breezy trade winds across the islands. This system’s position is relatively stationary but is expected to shift northward over the next few days, keeping the trade wind flow consistent.
Water vapor imagery reveals a compact upper-level low several hundred miles north of Hawaii, slowly drifting westward. Despite this nearby low, atmospheric soundings indicate a typical subsidence inversion just below 7,000 feet at Lihue and down to 5,000 feet at Hilo. Over the past 12 hours, rainfall amounts across the state have ranged from a quarter to a half inch, with more reports coming from Kaua’i and Oahu.
This weekend, a shortwave trough rotating around the upper low is expected to raise inversion heights, enhancing rainfall chances across the islands. Satellite imagery shows a band of cumulus clouds just outside the offshore waters, signaling a pocket of moisture that will bolster showers. While trade wind speeds may dip slightly, they are expected to remain borderline breezy. Most rainfall will concentrate over windward areas, though some showers may briefly reach leeward sides.
Looking ahead to early next week, models indicate another moisture pocket east of 140°W with higher total precipitable water values (about 1.6 to 1.8 inches) compared to this weekend’s moisture band (1.3 to 1.5 inches). The Global Forecast System (GFS) model is more aggressive in bringing this moisture across Hawaii Monday and Tuesday, while the European Centre for Medium-Range Weather Forecasts (ECMWF) model suggests a weaker signal. Either way, an increase in windward showers is expected early next week, with some rain reaching leeward areas as well. Notably, the National Blend of Models (NBM) predicts showers across the Kona slopes on the Big Island Monday afternoon more prominently than any other day in this forecast period.
After Tuesday, the islands are projected to return to a more typical summertime trade wind pattern, with showers mainly occurring at night and in the early morning. Wind speeds may increase slightly as the high-pressure system strengthens and drifts north.
Marine conditions remain a concern for boaters and coastal activities. A Small Craft Advisory remains in effect until 6 AM HST Saturday for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, and Big Island Southeast Waters. Trade winds are expected to fluctuate, with a possible brief lull on Saturday before strengthening again next week. Surf along south-facing shores is forecasted to remain small through the weekend due to a small background south-southwest swell. However, a small, long-period south swell is anticipated to build at the start of next week, peaking near average on Tuesday before tapering off later in the week.
East-facing shore surf, typically rough and choppy, may ease slightly over the weekend as trade winds lessen locally but should pick up again starting next week. Additionally, a tiny northwest swell may pass through early next week, providing small surf along north-facing shores Monday and Tuesday before flattening out.
Fire weather conditions remain fairly typical for the season. Despite increased trade wind showers over windward sections this weekend and early next week, afternoon relative humidities across leeward areas are expected to stay near summertime normals. Moderate to locally breezy trade winds will decrease slightly over the weekend before picking up again next week.
As the islands navigate this shifting weather pattern, residents and visitors are advised to stay updated on forecasts, especially if planning outdoor activities or marine excursions. The interplay of high pressure, moisture pockets, and trade winds promises a dynamic weather weekend, blending sunshine with showers in a classic Hawaiian summer dance.
