Jaco in Summer
In summer (June, July and August), Jaco sees average daytime highs around 27°C and overnight lows near 26°C, with 1393 mm of rain over about 87 wet days across the season. It is the 3rd-warmest season and the 2nd-wettest season.
Across summer, daytime highs hold fairly steady around 27°C. The sky is clear or mostly clear about 1% of the time across summer, and the air most often feels oppressive.
Summer is Jaco's weakest season of the year to visit on our travel score. Jaco has little temperature swing across the year, so its calendar seasons blur — the season framing matters less here than for a place with four distinct seasons. For the whole year in context, see Jaco's year-round climate.
- Avg daytime high
- 27°C
- 3rd-warmest season
- Avg overnight low
- 26°C
- Rainfall
- 1393 mm
- 87 wet days
- Avg wind
- 10 km/h
- Travel score
- 3.4
- weakest season of the year
- Months
- Jun · Jul · Aug
Temperature in Jaco in Summer
Across summer, daytime highs hold fairly steady around 27°C.
A typical summer day in Jaco reaches about 27°C and drops to 26°C overnight. The warmest of the three months is June, the coolest July.
Jaco weather by month
How the three summer months (June, July and August) 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 | 27° / 26° | 28 | 6.3 | 11.5 | 7.4 |
| Feb | 28° / 27° | 16 | 3.4 | 11.7 | 7.9 |
| Mar | 28° / 27° | 23 | 5.8 | 11.9 | 7.3 |
| Apr | 28° / 26° | 108 | 18.4 | 12.2 | 5.1 |
| May | 28° / 26° | 405 | 28.3 | 12.4 | 3.6 |
| Jun | 27° / 26° | 430 | 28.4 | 12.6 | 3.4 |
| Jul | 27° / 26° | 456 | 29 | 12.5 | 3.4 |
| Aug | 27° / 26° | 506 | 29.4 | 12.3 | 3.4 |
| Sep | 27° / 25° | 470 | 29.1 | 12.1 | 3.4 |
| Oct | 27° / 25° | 571 | 29.3 | 11.8 | 3.5 |
| Nov | 27° / 25° | 371 | 25.6 | 11.6 | 4.1 |
| Dec | 27° / 26° | 123 | 15.2 | 11.4 | 5.9 |
Cloud cover in Summer
The sky is clear or mostly clear about 1% of the time across summer.
Chance of precipitation in Summer
Jaco gets around 1393 mm of rain over 87 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 10 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 30 min in early June to 12 h 12 min by late August. 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 4.5 kWh/m².
Hazard calendar for Jaco
In summer, Jaco overlaps its rainy season season. The full year is below, with each hazard's peak months called out.
Jaco's rainy season runs May–November, when most of the year's rain falls.
Is summer a good time to visit Jaco?
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 Jaco.
What to pack for Jaco in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Jaco sees daytime highs around 27°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 87 days see rain.
Sea temperature near Jaco in Summer
The nearest coast averages about 29°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in April at about 29°C and coldest in November near 28°C.
The water stays above 20°C all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 28 | 28 | 28 |
| Comfort | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Tropical | Warm | Tropical |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 29 | Tropical |
| Feb | 29 | Tropical |
| Mar | 29 | Tropical |
| Apr | 29 | Tropical |
| May | 29 | Tropical |
| Jun | 29 | Tropical |
| Jul | 29 | Tropical |
| Aug | 29 | Tropical |
| Sep | 29 | Tropical |
| Oct | 28 | Tropical |
| Nov | 28 | Warm |
| Dec | 28 | Tropical |
UV index in Jaco in Summer
Clear-sky midday UV across summer averages around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Jaco peaks around March 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 9 (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) | 11 | 13 | 13 | 13 | 12 | 13 | 11 | 12 | 12 | 11 | 11 | 9 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Very high |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 11 | Extreme |
| Feb | 13 | Extreme |
| Mar | 13 | Extreme |
| Apr | 13 | Extreme |
| May | 12 | Extreme |
| Jun | 13 | Extreme |
| Jul | 11 | Extreme |
| Aug | 12 | Extreme |
| Sep | 12 | Extreme |
| Oct | 11 | Extreme |
| Nov | 11 | Extreme |
| Dec | 9 | Very high |
Air quality in Jaco 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 Jaco is worst in May — around 18 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (January, 9 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) | 9 | 10 | 11 | 16 | 18 | 16 | 17 | 15 | 14 | 12 | 11 | 9 |
| Level | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 9 | Good |
| Feb | 10 | Good |
| Mar | 11 | Good |
| Apr | 16 | Moderate |
| May | 18 | Moderate |
| Jun | 16 | Moderate |
| Jul | 17 | Moderate |
| Aug | 15 | Moderate |
| Sep | 14 | Moderate |
| Oct | 12 | Moderate |
| Nov | 11 | Good |
| Dec | 9 | Good |
Where is Jaco?
Jaco sits at 9.6°N, 84.6°W, 0 m above sea level, in Costa Rica. The nearest listed city is Esparza, 42 km away.
Topography around Jaco
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Jaco.
Within 3 km, the terrain around Jaco has significant variations in elevation — a maximum elevation change of 401 m around an average of 35 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 802 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,811 m.
The land around Jaco is covered by water (38%) and trees (31%) within 3 km, water (56%) and trees (35%) within 16 km, and trees (45%) and water (43%) within 80 km.
Costa Rica travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 59% of US
- price level, 2025
- GDP per capita
- $19,970
- 2025
- Happiness
- 7.4 / 10
- World Happiness, 2025
- Safe drinking water
- 81%
- of population, 2024
- Homicide rate
- 17.7
- per 100k, 2023
- Road deaths
- 14.8
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Moderate
- EF EPI 516
- 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 Jaco (9.615°, -84.6298°, elevation 0 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.