The single most common mistake people make when buying in Costa Rica is choosing a place in February. February is beautiful nearly everywhere. It tells you almost nothing about what living there is like in October.
Costa Rica packs an extraordinary range of climates into a small country, and the driver is altitude rather than latitude. Two places thirty minutes apart can differ by ten degrees and by two metres of annual rainfall. Choosing your climate is a more consequential decision than choosing your house, because you can renovate a house.
The two seasons, and why the names mislead
Costa Rica does not have four seasons. It has a dry season from roughly December to April and a green season from roughly May to November — and those labels apply properly only to the Pacific side.
Green season does not mean continuous rain. The typical pattern is clear mornings, building cloud, and rain in the afternoon or evening. Life adapts by moving outdoor activity to the morning. September and October are the wettest months on the Pacific and the point at which the pattern becomes genuinely persistent.
The Caribbean side follows a different rhythm entirely and does not share the Pacific dry season. It receives rain throughout the year, often with a relatively drier window around September and October — precisely when the Pacific is at its wettest.
Region by region
Guanacaste and the North Pacific. The driest and hottest part of the country. Dry season here is genuinely dry — brown landscape, dust, strong winds that can blow for days, and daytime heat that shapes the whole routine. Green season transforms it into somewhere lush. If you want reliable sun and beach heat, this is it. If you dislike heat, understand what you are signing up for.
The Central Valley. Roughly 1,000 to 1,500 metres, and the reason most Costa Ricans and most long-term foreign residents live here. Daytime temperatures generally sit in a comfortable range year-round, nights are cool, and air conditioning is largely unnecessary. Green season brings reliable afternoon rain. This is the most temperate, most liveable everyday climate in the country, and it is not a coincidence that the schools, hospitals and airport are here.
The Central and South Pacific. Warmer and considerably wetter than Guanacaste, with rainforest rather than dry forest. Manuel Antonio, Dominical, Uvita and the Osa are humid year-round with a heavy green season. Enormously biodiverse, and hard on buildings and belongings.
The Caribbean. Rain distributed through the year, high humidity, warm, with its own cultural character. Less developed for foreign residents, cheaper, and genuinely different in feel from the Pacific side.
The mountains and cloud forest. Monteverde, the Cerro de la Muerte corridor, San Gerardo de Dota. Cool to genuinely cold at night, misty, wet. People are frequently astonished that they need a fire in Costa Rica. Superb for anyone who dislikes heat.
The northern lowlands. Around Arenal, La Fortuna and Sarapiquí — warm, wet, green, with the volcano generating its own weather patterns.
Altitude as the control dial
A useful rule of thumb: temperature drops roughly 6°C for every 1,000 metres of elevation. That means you can select your temperature by choosing your altitude, and small changes matter. Moving from 800 metres to 1,400 metres in the same valley meaningfully changes how you sleep.
This is why buyers who think they must choose between "hot beach" and "cold mountain" are working with a false binary. The mid-altitude bands — 600 to 1,200 metres — contain a great deal of pleasant, underexplored country within reach of the coast.
The practical consequences for a house
- Humidity is the real enemy. In wet regions, expect mould on walls and leather, corrosion on electronics and hinges, and rapid decay of anything organic. Ventilation, dehumidifiers and material choice matter more than in temperate climates.
- Wind loading in Guanacaste. Dry-season winds are strong enough to affect roof design, landscaping and whether an outdoor dining area is usable.
- Water in dry regions. Guanacaste's dry season puts pressure on supply. Water availability letters and storage capacity are not paperwork details — they determine whether the property works.
- Drainage and landslides. In steep, wet terrain, how the site sheds water is a structural question. Ask about slope stability and historic slides.
- Cooling costs. Air conditioning at the coast is a substantial and continuous electricity expense. Central Valley houses often need none.
- Insects and screening. Wet lowland regions require serious screening and sealing. This is a design decision, not an afterthought.
How to choose properly
Visit in the worst month for the region, not the best. For the Pacific, that means late September or October. For Guanacaste, also visit in March to feel the heat and wind at full strength. Rent before buying — a rainy season in place teaches you more than five dry-season inspections.
Ask locals the specific question: what is the hardest month here, and why. People will tell you honestly, and the answer is often something you would not have thought to ask about — a wind, a road, a smell, a period when everything stays damp.
Reading a property for its climate
Beyond the region, the specific site matters more than buyers expect. Aspect determines how much sun a house takes and when — an east-facing terrace is pleasant in the morning and a west-facing one is punishing at four in the afternoon in the lowlands. Ridge positions catch breeze and also catch wind; valley floors are still, hotter by day and prone to pooling cold air and mist at night.
Ask how the house was built for the climate it is in. Deep eaves, cross-ventilation, raised floors and covered outdoor space are the marks of someone who understood the site. Sealed, air-conditioned boxes imported from a temperate design vocabulary tend to age badly here and cost a fortune to run.
The seasonal rhythm of daily life
One thing nobody mentions: the seasons change how the country behaves, not just how it looks. Dry season is when roads are passable, construction happens, tourism peaks and social life is busiest. Green season is quieter, cheaper, greener, and the months when locals get things done. Neither is better. But if you visit only in one, you have met half the country.
Common questions
Which region has the best year-round weather?
The Central Valley, by most people's definition — mild days, cool nights, no need for heating or cooling. It is also the least dramatic scenically, which is the trade-off.
Is green season a bad time to visit?
No. Mornings are frequently clear, the country is at its greenest, prices are lower and there are fewer visitors. It is arguably the better time to assess a place honestly.
Does Costa Rica get hurricanes?
Direct hurricane strikes are rare compared with much of the Caribbean, though passing systems can bring heavy rain and flooding, particularly on the Caribbean side and in the north.
Do I need air conditioning?
At the coast, generally yes. In the Central Valley, usually not. In the mountains, you may want heating instead.
How much does altitude really change things?
Substantially. A few hundred metres can be the difference between sleeping comfortably without cooling and running air conditioning nightly.
Choose the climate first
We would rather match you to the right region than sell you the first house you like. Tell us how you handle heat, humidity and rain, and we will narrow the map before we start sending listings.
Book a consultation to start there.
General information only — not legal or tax advice. Weather patterns vary year to year; confirm site-specific conditions locally.