Costa Rica in October: Turtle Season Closes, Leatherbacks Begin, and Dry Season Approaches

October is Costa Rica’s final month of transition. The Guanacaste dry season typically begins arriving in November, and late October sometimes delivers the first glimpse of what’s coming — a few clearer mornings and slightly lighter afternoon rain. The Caribbean’s Tortuguero turtle nesting season is winding down as the last green sea turtles nest and the final hatchlings emerge. On the Pacific side, the leatherback turtle nesting season opens at Playa Grande (Las Baulas National Park) in October — a different and extraordinary turtle experience. October also sees the Limón Carnival — the Caribbean coast’s biggest cultural event.

Weather & Conditions

Guanacaste: 23–31°C. Still rainy season but beginning to ease by late October.

Manuel Antonio: 23–29°C. Rain. Transitioning.

Arenal: 19–25°C. Heavy rain. Still the wet season.

Caribbean (Tortuguero): 23–28°C. Heavy rain. Turtle season closing.

Nicoya Peninsula: 23–31°C. Easing rain toward late October.

What to Do

Leatherback turtle nesting, Playa Grande (Las Baulas National Park): October marks the opening of the leatherback nesting season on the Pacific coast. The leatherback (Dermochelys coriacea) is the world’s largest sea turtle — females can reach 900kg. Playa Grande on the northern Nicoya Peninsula is one of the most important leatherback nesting sites in the Pacific. The season runs October–February. Ranger-guided night tours (similar to Tortuguero’s system) operate from the Las Baulas National Park entrance. Book through the park or the adjacent Hotel Las Tortugas.

Caribbean Carnival — Limón (Carnaval de Limón, mid-October): Puerto Limón’s 10-day carnival in the week around October 12 (Columbus Day, here celebrated as Día de las Culturas) is the Caribbean coast’s largest cultural event. The Afro-Caribbean character of the event — steel drums, reggae, calypso music, Caribbean food, and dancing — is entirely different from the mainland Costa Rican culture. The parade on the final Saturday is the centerpiece.

Tortuguero — final turtle activity and hatching: The green sea turtle nesting season at Tortuguero ends in October. Early October still has some nesting activity; late October primarily sees hatchling emergence. This is the final window for the Tortuguero turtle experience before the season closes. The lodges operate through October.

Pacific coast recovering — first October improvements: Late October in Guanacaste begins the transition toward dry season. The last weeks of October sometimes bring the first clear mornings and lighter showers that signal November’s arrival. Early travelers who arrive late in October occasionally get the green season’s low prices with the first glimpse of dry season conditions.

Arenal volcano and jungle activities: October’s heavy Arenal rain means the waterfalls are still at maximum flow (La Fortuna Waterfall, Río Celeste). The hot springs run year-round regardless of rain. The La Fortuna town infrastructure is fully operational.

Festivals & Events

Día de las Culturas (October 12): The Costa Rican equivalent of Columbus Day, reframed as a celebration of cultural diversity. In Puerto Limón, it’s the heart of Carnival.

Carnaval de Limón (mid-October): 10 days of Caribbean celebration centered on the Puerto Limón waterfront.

Practical Tips

Limón Carnival logistics: Puerto Limón is 3–4 hours from San José by road (MEPE buses run regularly, or drive the Route 32). Accommodation in Puerto Limón is limited — book well ahead for carnival week. Alternatively, base in San José and travel to Limón for parade day.

Las Baulas National Park tours: the leatherback night tours run on a strict system. Only 15 visitors are allowed on the beach at any time, accompanied by a guide and ranger with radio contact to active nests. Book through the park or Hotel Las Tortugas (directly adjacent to the beach).

Late October Guanacaste: the weather improvement is not guaranteed. Check forecasts. Some years late October is still fully wet; others give a genuine preview of dry season.

October car rental: prices are still green season rates — lower than January. 4WD still recommended for coastal and Osa access routes.

Who October Is For

Leatherback turtle opening season visitors. Carnaval de Limón cultural travelers. Final Tortuguero turtle hatching observers. Travelers who want October’s green season prices with the knowledge that November’s dry season is weeks away. And travelers combining the Caribbean carnival with the Pacific leatherback season in a single visit.