Jaco in Fall
In fall (September, October and November), Jaco sees average daytime highs around 27°C and overnight lows near 25°C, with 1411 mm of rain over about 84 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Across fall, daytime highs hold fairly steady around 27°C. The sky is clear or mostly clear about 4% of the time across fall, and the air most often feels oppressive.
Fall is Jaco's 3rd-best season 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
- coldest season of the year
- Avg overnight low
- 25°C
- Rainfall
- 1411 mm
- 84 wet days
- Avg wind
- 11 km/h
- Travel score
- 3.7
- 3rd-best season
- Months
- Sep · Oct · Nov
Temperature in Jaco in Fall
Across fall, daytime highs hold fairly steady around 27°C.
A typical fall day in Jaco reaches about 27°C and drops to 25°C overnight. The warmest of the three months is September, the coolest October.
Jaco weather by month
How the three fall months (September, October and November) 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 Fall
The sky is clear or mostly clear about 4% of the time across fall.
Chance of precipitation in Fall
Jaco gets around 1411 mm of rain over 84 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 11 km/h across fall.
Sunrise & sunset in Fall
Daylight runs from about 12 h 12 min in early September to 11 h 30 min by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 4.3 kWh/m².
Hazard calendar for Jaco
In fall, 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 fall a good time to visit Jaco?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a weaker month for outdoor sightseeing in Jaco.
What to pack for Jaco in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, Jaco sees daytime highs around 27°C and nights near 25°C. Pack rain gear. Worth having: light clothes and sun protection. About 84 days see rain.
Sea temperature near Jaco in Fall
The nearest coast averages about 28°C across fall — 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 Fall
Clear-sky midday UV across fall averages around 11 (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 Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall 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.