Jacó Costa Rica Weather: Year-Round Climate Guide

Jacó sits on Costa Rica's Central Pacific coast in a zone that receives substantially more rainfall than Guanacaste but less than the Southern Pacific near the Osa Peninsula. Annual rainfall in Jacó averages 100–130 inches (2,540–3,300 mm), distributed across most months of the year. Even during the dry season (December–April), Jacó receives measurable rainfall—typically 1–4 inches per month—unlike Guanacaste which can go weeks without a drop.

This continuous moisture means Jacó is verdant and green year-round. The surrounding mountains and nearby Carara National Park maintain lush tropical forest regardless of season. This makes Jacó weather somewhat different from what travelers expect if they're used to other tropical destinations with sharply defined dry seasons.

Temperatures in Jacó are consistently warm throughout the year. Daytime highs range from 84–90°F (29–32°C) depending on the month, with slightly lower temperatures during the rainy season due to cloud cover and rain. Overnight lows range from 73–77°F (23–25°C). The humidity is high year-round—typically 75–85%—making Jacó feel warm and tropical in every season.

Jacó's dry season (December through April) brings the most consistently sunny weather of the year, but it's a relative term. Unlike Guanacaste where 'dry season' means almost no rain, Jacó in January might still receive 2–3 inches of rainfall—typically as brief afternoon showers rather than sustained rain. Mornings are almost always sunny and clear, and full dry days are common, particularly January through March.

January and February are Jacó's driest months, averaging 1–2 inches (25–51 mm) per month. This is the optimal beach season, with reliable morning sunshine, warm calm morning seas, and the best snorkeling visibility of the year. The surf at Jacó Beach itself is not ideal for swimming—rip currents are present year-round—but Playa Herradura just north and Playa Hermosa just south offer better swimming and world-class surfing respectively.

March and April see temperatures at their highest (88–92°F/31–33°C) and rainfall beginning to increase slightly toward the rainy season. The landscape around Jacó remains green due to rainfall from surrounding mountains feeding the rivers, making dry-season Jacó look greener than Guanacaste during the same period.

The rainy season in Jacó runs from approximately May through November, with rainfall peaking in September and October. May begins with increasing afternoon rains, gradually shifting to the classic tropical pattern of sunny mornings and afternoon thunderstorms. By July and August, significant rainy periods occur most days, though mornings remain largely clear.

September and October are the wettest months in Jacó. Monthly rainfall can reach 20–25 inches (508–635 mm) during these months. Multi-day rain events occasionally occur, and flooding in low-lying areas of town is possible after very heavy rainfall. The surf is at its most powerful in September–October due to strong south swells.

Despite the rains, Jacó remains functional and enjoyable during the rainy season. The town's bars, restaurants, and nightlife operate year-round. Surf conditions actually improve significantly during the rainy season, making Jacó more attractive to serious surfers in July through October than in the dry season. Hotel prices drop 25–40% from their dry season peaks.

January: High 88°F (31°C), Low 73°F (23°C), Rainfall 1.5 in (38 mm). Driest month. Best beach conditions.

February: High 88°F (31°C), Low 73°F (23°C), Rainfall 1.2 in (30 mm). Similar to January. Excellent weather.

March: High 90°F (32°C), Low 74°F (23°C), Rainfall 1.8 in (46 mm). Hottest, sunniest month. Spring break crowds.

April: High 90°F (32°C), Low 74°F (23°C), Rainfall 4.5 in (114 mm). First rains arriving. Still mostly sunny mornings.

May: High 87°F (31°C), Low 74°F (23°C), Rainfall 14.5 in (368 mm). Full rainy season. Big transition month.

June: High 85°F (29°C), Low 73°F (23°C), Rainfall 16.2 in (411 mm). Heavy afternoon rains. Mornings usually clear.

July: High 84°F (29°C), Low 73°F (23°C), Rainfall 14.5 in (368 mm). Good surf. Mornings sunny. Waterfalls spectacular.

August: High 84°F (29°C), Low 73°F (23°C), Rainfall 16.4 in (417 mm). Consistent rainy pattern. Great for surfers.

September: High 83°F (28°C), Low 73°F (23°C), Rainfall 22.5 in (572 mm). Wettest month. Powerful surf. Cheapest prices.

October: High 83°F (28°C), Low 73°F (23°C), Rainfall 21.8 in (554 mm). Very wet. Heavy surf. Off-season bargains.

November: High 84°F (29°C), Low 73°F (23°C), Rainfall 14.2 in (361 mm). Rains tapering. Conditions improving.

December: High 86°F (30°C), Low 73°F (23°C), Rainfall 4.5 in (114 mm). Dry season returning. Good conditions by mid-month.

Jacó and its neighboring Playa Hermosa are significant surf destinations on the Pacific coast. Conditions vary by season, but surf is present year-round at both locations.

Dry season (December–April): North swells can produce good waves at some beach breaks, but this is generally the lower-energy surf season at Jacó. Playa Hermosa receives consistent beach break year-round. The winds in the dry season are more consistent and can affect wave quality with onshore wind effects by afternoon.

Rainy season (May–November): The Pacific south swell season ramps up in May and reaches peak intensity in July–October. These south swells deliver the best and most powerful waves of the year to Jacó's beaches and Playa Hermosa. Playa Hermosa is a renowned Costa Rican surf competition venue and frequently hosts professional events during this peak season. The annual Surf City Jacó competitions are typically held during this rainy season swell period.

For beach vacations and general tourism: January through March offers the most reliable sunshine and lowest rainfall. These dry season months give Jacó its best beach conditions for swimming (at Herradura and protected areas), snorkeling (at nearby sites), and general outdoor activities. This is also peak season with higher prices and more tourists, particularly on weekends.

For surfing: July through October delivers the strongest south swells and best conditions for intermediate to advanced surfers. Playa Hermosa is at its most dynamic during this period. The rainy season's 25–40% price discounts and smaller crowds make this an excellent time for dedicated surf trips.

For value travel: May, June, and November offer a good balance—prices 20–30% below peak, manageable rainy season conditions (not the heaviest months), and access to all of Jacó's restaurants, bars, and activities at full operation.

Year-round essentials for Jacó: strong sunscreen (SPF 50+), swimwear, quick-dry clothing, sandals and closed-toe walking shoes, insect repellent, and a hat. The heat and humidity at Jacó's sea level location make lightweight, breathable fabrics essential—cotton feels stifling in Jacó's humidity; synthetic moisture-wicking fabrics are far more comfortable.

For rainy season visits (May–November): add a lightweight waterproof rain jacket or poncho (compact enough to fit in a daypack), waterproof sandals, and a dry bag for electronics during beach and boat activities. The afternoon rains at Jacó are often heavy enough that an umbrella won't cut it—a proper rain jacket is more effective.