Costa Rica in Summer
In summer (December, January and February), Costa Rica sees average daytime highs around 29°C and overnight lows near 21°C, with 687 mm of rain over about 75 wet days across the season. It is the 2nd-warmest season and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 29°C. The sky is clear or mostly clear about 9% of the time across summer, and the air most often feels muggy.
Summer is Costa Rica's weakest season of the year to visit on our travel score. For the whole year in context, see Costa Rica's year-round climate.
- Avg daytime high
- 29°C
- 2nd-warmest season
- Avg overnight low
- 21°C
- Rainfall
- 687 mm
- 75 wet days
- Avg wind
- 7 km/h
- Travel score
- 3.3
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Costa Rica in Summer
Across summer, daytime highs hold fairly steady around 29°C.
A typical summer day in Costa Rica reaches about 29°C and drops to 21°C overnight. The warmest of the three months is December, the coolest December.
How summer really feels in Costa Rica
Once humidity and wind are folded in, summer brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Costa Rica weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 29° / 21° | 256 | 26.2 | 13 | 3.3 |
| Feb | 29° / 21° | 215 | 23.6 | 12.6 | 3.3 |
| Mar | 30° / 21° | 181 | 23.8 | 12.1 | 3.6 |
| Apr | 29° / 20° | 81 | 12.4 | 11.6 | 5.0 |
| May | 28° / 18° | 39 | 5.7 | 11.1 | 7.0 |
| Jun | 28° / 17° | 18 | 2.4 | 10.9 | 7.9 |
| Jul | 28° / 16° | 11 | 1.4 | 11 | 7.6 |
| Aug | 30° / 18° | 17 | 2.5 | 11.4 | 6.0 |
| Sep | 31° / 20° | 67 | 8.7 | 11.9 | 4.5 |
| Oct | 31° / 21° | 129 | 18.5 | 12.4 | 3.7 |
| Nov | 30° / 21° | 175 | 22.2 | 12.9 | 3.5 |
| Dec | 29° / 21° | 217 | 25.6 | 13.1 | 3.4 |
Cloud cover in Summer
The sky is clear or mostly clear about 9% of the time across summer.
Chance of precipitation in Summer
Costa Rica gets around 687 mm of rain over 75 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 7 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 hours in early December to 12 h 24 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.6 kWh/m².
Hazard calendar for Costa Rica
In summer, Costa Rica overlaps its monsoon season. The full year is below, with each hazard's peak months called out.
Costa Rica's monsoon runs October–March, when most of the year's rain falls.
Is summer a good time to visit Costa Rica?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a weaker month for outdoor sightseeing in Costa Rica.
What to pack for Costa Rica in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Costa Rica sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 75 days see rain.
UV index in Costa Rica in Summer
Clear-sky midday UV across summer averages around 15 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Costa Rica peaks around January 22 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 7 (very high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 15 | 15 | 14 | 11 | 8 | 7 | 8 | 9 | 9 | 10 | 13 | 14 |
| Level | Extreme | Extreme | Extreme | Extreme | Very high | Very high | Very high | Very high | Very high | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 15 | Extreme |
| Feb | 15 | Extreme |
| Mar | 14 | Extreme |
| Apr | 11 | Extreme |
| May | 8 | Very high |
| Jun | 7 | Very high |
| Jul | 8 | Very high |
| Aug | 9 | Very high |
| Sep | 9 | Very high |
| Oct | 10 | Extreme |
| Nov | 13 | Extreme |
| Dec | 14 | Extreme |
Air quality in Costa Rica in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Costa Rica is worst in September — around 24 µg/m³ PM2.5 (moderate), about 5.2× the cleanest month (June, 5 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 7 | 7 | 6 | 5 | 5 | 5 | 8 | 10 | 24 | 12 | 6 | 6 |
| Level | Good | Good | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 7 | Good |
| Feb | 7 | Good |
| Mar | 6 | Good |
| Apr | 5 | Good |
| May | 5 | Good |
| Jun | 5 | Good |
| Jul | 8 | Good |
| Aug | 10 | Good |
| Sep | 24 | Moderate |
| Oct | 12 | Moderate |
| Nov | 6 | Good |
| Dec | 6 | Good |
Where is Costa Rica?
Costa Rica sits at 18.5°S, 53.1°W, 646 m above sea level, in Brazil. The nearest listed city is Chapadão do Sul, 60 km away.
Topography around Costa Rica
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Costa Rica.
Within 3 km, the terrain around Costa Rica has only modest variations in elevation — a maximum elevation change of 160 m around an average of 655 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 307 m; within 80 km, large variations in elevation — a maximum elevation change of 616 m.
The land around Costa Rica is covered by grassland (39%) and trees (22%) within 3 km, cropland (41%), grassland (28%) and trees (27%) within 16 km, and cropland (42%), grassland (31%) and trees (23%) within 80 km.
Brazil travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type C / N
- 127 / 220 V · 60 Hz
- Prices
- ≈ 46% of US
- price level, 2025
- GDP per capita
- $10,713
- 2025
- Happiness
- 6.6 / 10
- World Happiness, 2025
- Safe drinking water
- 89%
- of population, 2024
- Homicide rate
- 19.3
- per 100k, 2023
- Road deaths
- 16
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 482
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Costa Rica (-18.5439°, -53.1292°, elevation 646 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.