December on the Big Island delivers a blend of reliable sunshine, gentle breezes, and cooler evenings that appeal to travelers seeking island warmth during the winter season. While trade winds keep humidity comfortable, shrinking crowds and festive events add extra charm to this time of year.
Below is a concise snapshot of what to expect, followed by dedicated sections that explore conditions by region, activities, and practical planning tips.
| Location | Avg High Temp | Avg Low Temp | Rainfall | Ocean Temp |
|---|---|---|---|---|
| Hilo (East) | 81°F (27°C) | 66°F (19°C) | 2.5–3 in | 75°F (24°C) |
| Kona (West) | 84°F (29°C) | 64°F (18°C) | 1.2–1.8 in | 76°F (24°C) |
| Waimea (Upcountry) | 78°F (26°C) | 58°F (14°C) | 2.0–2.5 in | 74°F (23°C) |
| Park City & Summit | 72°F (22°C) | 52°F (11°C) | 3.0–4.0 in | 73°F (23°C) |
Hilo Coast December Weather Patterns
Along the Hilo coast, December brings refreshing trade winds and steady tradewind showers that nourish lush rainforests. Average highs remain in the low 80s°F, while overnight lows dip into the mid 60s, creating a mild yet occasionally damp environment.
Rainfall is more common here than on the drier west side, so short, intense bursts are typical rather than all-day drizzle. Visitors should anticipate quick showers followed by sunshine, especially in the late morning and afternoon.
Water temperatures stay comfortable for snorkeling around popular black sand beaches, and surf along this coastline can build during passing storm systems. Packing a light rain jacket and waterproof footwear helps make spontaneous downpours more enjoyable.
Kona Side December Climate
The Kona side bakes under clearer skies in December, with less rainfall and more consistent sunshine compared to Hilo. Daytime highs often reach the mid 80s°F, while evenings cool into the low 60s, making layered clothing ideal.
Lows rarely drop to uncomfortable levels, and humidity feels moderate thanks to steady breezes from the ocean. This combination of warmth and airflow makes afternoon drives along the coast especially pleasant.
Diving and manta ray season remain strong during this month, as calm seas and good visibility attract both marine life and photographers. Remember that sunscreen, a hat, and hydration are essential even when clouds drift overhead.
High Elevation December Weather
Upcountry areas such as Waimea and Volcano experience noticeably cooler conditions in December, with daytime highs in the upper 70s and lows that can flirt with the 50s at higher spots.
Rainfall increases with elevation, and brief mountain showers are common, so driving between towns can bring sudden changes in visibility and road surface conditions.
Visitors heading to Hawaii Volcanoes National Park should prepare for variable weather, including wind and mist near the crater rim, while still enjoying crisp air and dramatic cloud formations over the landscape.
Planning Activities in December
December is a popular month to visit the Big Island, so booking tours, car rentals, and accommodations well in advance is strongly recommended. Surf lessons, cultural workshops, and rainforest hikes fill quickly as travelers take advantage of favorable weather windows.
Flexibility with timing helps maximize dry periods, especially for outdoor adventures like hiking, snorkeling, or stargazing at dark-sky sites. Keeping a lightweight rain layer and sun protection in the daypack covers most weather scenarios.
Festive island events and holiday markets add local flavor to visits, offering chances to sample seasonal treats and crafts while supporting community hosts during a busy season.
Key Takeaways for December Big Island Travel
- Kona side stays drier and sunnier, while Hilo side sees more frequent rain showers.
- Ocean temperatures are warm enough for snorkeling and diving, especially on the western coast.
- Upcountry and volcano areas are cooler and can be wetter, requiring flexible clothing layers.
- Advance bookings for tours, rentals, and lodging are essential due to higher winter demand.
- Packing rain gear, sun protection, and layers ensures comfort across different regions and elevations.
FAQ
Reader questions
Is December a good month for snorkeling on the Big Island?
Yes, December offers warm ocean temperatures, decent visibility, and calmer conditions on the Kona side, making it excellent for snorkeling and manta ray encounters.
Should I pack rain gear for a December trip to Hilo?
Absolutely, Hilo sees more frequent showers in December, so a compact rain jacket and waterproof shoes will keep you comfortable during rainforest walks and coastal explorations.
What clothing is best for evenings in Waimea in December?
Light layers work best, including a long-sleeve shirt, fleece or light jacket, and closed-toe shoes, since temperatures can drop into the 50s after sunset.
Are major roads and parks accessible in December on the Big Island?
Most roads and parks remain open, but high-elevation routes can experience temporary closures due to rain, so checking conditions before heading upcountry is advisable.