Residents and visitors on Hawaii's Big Island can expect a mix of sun and clouds on Wednesday, July 29, 2026, as the National Weather Service issues its daily forecast. The day will feature passing showers, especially over windward and mauka areas, with breezy trade winds continuing across the island. Here's what you need to know to plan your day safely and comfortably.

Morning Conditions and Wind Patterns

The morning will start with partly cloudy skies and a few isolated showers, particularly along the Hamakua Coast and Hilo side. Temperatures are expected to range from the mid-70s to low 80s at sea level, with cooler readings at higher elevations. The trade winds will be moderate to breezy, with gusts possible in exposed areas, which could affect outdoor activities and driving, especially for high-profile vehicles.

According to the forecast, wind speeds will likely average 10 to 20 miles per hour, with higher gusts near the coasts and over passes. The breeze will help keep humidity levels in check, but it also means that any showers will move quickly. Sunrise is expected around 5:55 a.m., and by mid-morning, the sun may peek through the clouds in leeward spots like Kona and Kohala.

UV Index and Air Quality

The UV index is forecast to be high, so residents and tourists alike should apply sunscreen, wear hats, and seek shade during peak sun hours from 10 a.m. to 4 p.m. Air quality is expected to remain good, with no volcanic smog or vog advisories in effect for the day, as trade winds keep particulates dispersed.

Afternoon Showers and Thunderstorm Potential

In the afternoon, the chance of showers increases, especially over windward slopes and interior areas. The National Weather Service notes that an unstable air mass may trigger brief heavy downpours and isolated thunderstorms, particularly in the upper elevations of Mauna Kea and Mauna Loa. While severe weather is not anticipated, sudden downpours can lead to ponding on roads and reduced visibility.

Leeward areas, including the Kona coast and Waikoloa, will likely see less rain, but clouds may build in the afternoon, offering some relief from the sun. Temperatures will peak in the low to mid-80s at the coast, with cooler conditions at higher altitudes. Residents in flood-prone areas should stay alert to any rapid changes in weather, though no flash flood watches are currently in effect.

Marine and Surf Forecast

For ocean enthusiasts, the marine forecast calls for choppy seas in channels, with north-facing shores seeing a small northwest swell. Surf heights are expected to be 2 to 4 feet on north and west shores, while south shores may see 1 to 3 feet. Winds will make for bumpy conditions for small boats, so mariners should check the latest marine advisories before heading out.

Evening Outlook and Weekend Trend

As evening approaches, showers will diminish, but isolated light rain may persist over windward areas overnight. Lows will dip into the lower 70s at sea level, with cooler temperatures in the mountains. The trade winds will continue through the night, providing a comfortable and breezy evening for outdoor dining or evening walks.

Looking ahead, the forecast suggests that the trade wind pattern will persist into the weekend, with typical windward showers and mostly sunny leeward conditions. No major storm systems are on the horizon, but residents are encouraged to monitor updates for any changes, especially as we move into the peak of the hurricane season.

Safety Tips for Outdoor Activities

  • Stay hydrated: Even with breezy conditions, the tropical sun can cause dehydration.
  • Check road conditions: Heavy showers can cause slippery roads, especially on Highway 11 and Saddle Road.
  • Secure loose items: Strong gusts can blow umbrellas, patio furniture, or other light objects.
  • Use caution at beaches: Rip currents are possible, especially on north-facing shores.

Key Takeaways

Overall, July 29 will be a typical trade wind day on the Big Island, with a mix of sun and clouds, passing showers in windward and mauka areas, and breezy conditions. Temperatures will be seasonable, and no major weather hazards are expected. However, the public should remain aware of the potential for brief heavy rain and gusty winds, and always check the latest forecast from the National Weather Service before making outdoor plans. Stay safe and enjoy the island's natural beauty, whatever the sky brings.