Costa Rica Weather in December: Your Complete Guide

December marks the beginning of Costa Rica's dry season on the Pacific coast. After six months of afternoon rains, skies clear and the trade winds from the north bring cool, dry air from the Caribbean into the Pacific lowlands. The result is predominantly sunny days, lower humidity, and excellent conditions for outdoor activities.

In the Central Valley, including San José, December brings consistently dry and clear weather. The surrounding mountains turn green after the rains, creating beautiful scenery with fresh, clean air. Nights in the highlands can be quite cool—reaching into the low 60s°F (15–17°C)—making sweaters welcome in the evenings.

December in Costa Rica has a split personality: the first two weeks often retain some transition-season rain on parts of the Pacific coast, while the final two weeks (Christmas through New Year's) are typically very dry. The Caribbean coast, as always, follows its own rhythm, receiving more rainfall in December as its wetter season begins.

Guanacaste beaches (Tamarindo, Flamingo, Conchal): Highs of 88–92°F (31–33°C), Lows of 72–76°F (22–24°C). Hot and sunny by midday, with pleasant evenings.

Central Pacific (Jacó, Manuel Antonio): Highs of 86–90°F (30–32°C), Lows of 72–74°F (22–23°C). Excellent beach weather, particularly after mid-December.

San José and Central Valley: Highs of 77–80°F (25–27°C), Lows of 60–64°F (15–18°C). Pleasantly warm days and cool evenings.

La Fortuna / Arenal: Highs of 80–83°F (27–28°C), Lows of 66–70°F (19–21°C). Warm with reducing but still regular afternoon rains.

Monteverde Cloud Forest: Highs of 65–70°F (18–21°C), Lows of 55–60°F (13–15°C). Cool and misty; jacket required.

Caribbean Coast (Puerto Viejo, Limón): Highs of 82–86°F (28–30°C), Lows of 72–74°F (22–23°C). Entering wetter period; variable conditions.

December rainfall varies significantly by region. In Guanacaste, December typically receives only 0.5–1.5 inches (13–38 mm) of rain for the entire month—essentially minimal. The Central Pacific sees 2–4 inches (51–102 mm) of rain in December, primarily in the first half of the month. By late December, even Manuel Antonio and Jacó settle into dry season patterns.

Humidity drops noticeably from the rainy season's peak levels. In Pacific coastal areas, relative humidity in December ranges from 65–75%, compared to 80–90% during September and October. This makes outdoor activities significantly more comfortable, especially hiking and physical tours.

San José sees only about 1.5 inches (38 mm) of rain in December, concentrated in the first week. After that, the capital enjoys some of its clearest, driest weather of the year. The surrounding mountains visible from the city are sharp and detailed against blue skies during the dry season months.

December is a spectacular month for Costa Rica's Pacific coast. From Guanacaste in the north down through Manuel Antonio and the Central Pacific, December brings the beginning of dry season sunshine. Beach days feature brilliant blue skies, calm waters, and manageable heat—typically 86–92°F (30–33°C) at midday with sea breezes offering welcome cooling.

Surf conditions in December can be excellent along the Pacific. The swell season from the north brings waves to beaches like Nosara, Tamarindo, and Witch's Rock in Guanacaste. Jacó and Playa Hermosa on the Central Pacific also see good conditions. December is one of the better months for intermediate and advanced surfers on the Pacific coast.

Snorkeling and diving visibility improves dramatically in December compared to the rainy season. Calmer seas and clearer water make spots like Isla del Caño, the Bat Islands in Guanacaste, and various beach reef zones much more rewarding. Whale watching in the Southern Pacific (Drake Bay area) continues in December, with humpback whales still present through January.

The Caribbean coast in December is entering its wetter season, making it less ideal for beach vacations compared to other times of year. Cahuita National Park and Puerto Viejo de Talamanca can receive significant rainfall throughout December, and seas can be rough for swimming and snorkeling.

However, Tortuguero National Park—famous for sea turtle nesting—has a different appeal in December. While turtle nesting season has ended (peak was July–September), the park's canal system offers excellent wildlife viewing year-round. Manatees, river otters, caimans, and abundant birdlife make Tortuguero rewarding in any month.

December is Costa Rica's most festive month. The country celebrates Christmas with elaborate light displays in towns across the Central Valley. The Festival de la Luz (Festival of Light) parade in San José typically takes place in mid-December and draws huge crowds. Many families from across Costa Rica travel to beach destinations during the holiday period.

The last two weeks of December (Dec 16–31) are the busiest and most expensive travel period of the year in Costa Rica. Hotels at popular Pacific beach destinations like Tamarindo, Manuel Antonio, and Jacó often sell out 3–5 months in advance for the Christmas–New Year's period. Flight prices are also at their annual peak. Book everything as early as possible if traveling during this window.

New Year's Eve is celebrated enthusiastically throughout Costa Rica, with beach towns hosting parties and fireworks. Tamarindo, Jacó, and Puerto Viejo (Caribbean) all have notable celebrations. Many locals ring in the New Year on the beach, creating a festive and crowded atmosphere.

December calls for beach-ready clothing: lightweight breathable fabrics, swimwear, shorts, and t-shirts for coastal and lowland areas. Strong sunscreen (SPF 50+) is essential—the tropical sun is intense even in December, and UV exposure is high year-round at this latitude.

Despite the warm beach weather, pack at least one light jacket or sweater. San José evenings can reach the low 60s°F (15–17°C), and Monteverde Cloud Forest requires a warm layer even in the dry season. If visiting multiple climate zones, the layering strategy is key.

An umbrella or compact rain jacket is still useful for early December, particularly if visiting the Central Pacific. By late December the chances of rain are low on the Pacific coast, but the Central Valley can still see an occasional shower. The Caribbean coast requires rain gear throughout December.