Climate and average weather in Kourou

In Kourou, the weather is muggy, hot, wet, and mostly clear and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around May.

Best: early August to mid November

Over the course of the year, the temperature in Kourou typically varies from 24°C to 30°C, and is rarely below 24°C or above 30°C. October is the hottest month of the year, while January is the coldest.

Based on the travel score, the best times of year to visit Kourou for warm-weather activities are from early March to late March and early August to mid November.

Hottest
Oct
30°
Coldest
Jan
24°
Wettest
May
392 mm
Driest
Sep
40 mm
Rain / yr
2322 mm
267 wet days
Daylight
11.7–12.3 h
shortest–longest
Elevation
7 m
5.2°N
Clearest
Sep
38% cloud

Kourou weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early August to mid November.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Kourou, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

Temperatures in Kourou stay fairly even through the year, without a distinct hot or cool season. The warmest month is October, with an average high of 30°C and low of 25°C; the coolest is January, with an average low of 24°C and high of 27°C.

Days typically run about 4°C warmer than nights year-round.

20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2724
Feb2724
Mar2825
Apr2825
May2825
Jun2824
Jul2924
Aug2925
Sep2925
Oct3025
Nov2925
Dec2824

How hot and cold Kourou really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Kourou feels like about 34°C (around October 12). About 135 days a year carry some heat stress, peaking in October.

20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan30272424
Feb30272424
Mar30282525
Apr31282525
May31282525
Jun31282424
Jul32292424
Aug33292525
Sep34292525
Oct34302525
Nov33292525
Dec31282424

Average hourly temperature in Kourou

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on October afternoons, near 30°C, and coldest before dawn in January, near 24°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Kourou weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 24°2362611.74.1
Feb27° / 24°19122.511.84.2
Mar28° / 25°16523.8124.3
Apr28° / 25°23625.312.14.0
May28° / 25°39228.912.23.6
Jun28° / 24°34628.712.33.4
Jul29° / 24°2042612.33.8
Aug29° / 25°9016.812.24.8
Sep29° / 25°4010125.5
Oct30° / 25°491211.95.2
Nov29° / 25°12820.411.84.2
Dec28° / 24°24426.911.73.8

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Kourou gets about 2322 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 8.1 months, from around Nov 23 to Jul 28, peaking in May at about 97% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Sep 21.

May is the wettest month by volume, with 392 mm over about 29 wet days; September is the driest, with 40 mm.

0%10%20%30%40%50%60%70%80%90%100%110%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetMay 27 · 97%Sep 21 · 33%
Rain on a day (%)Rain days
Jan8326
Feb8023
Mar7724
Apr8425
May9329
Jun9529
Jul8426
Aug5517
Sep3410
Oct4012
Nov6720
Dec8627

Monthly rainfall

Over a full year, Kourou collects about 2322 mm of rain across 267 wet days — roughly 194 mm in an average month.

It doesn’t fall evenly. May is the wettest month with 392 mm, while September is the driest at just 40 mm. The three wettest months alone bring about 42% of the year’s total.

050100150200250300350400450JanFebMarAprMayJunJulAugSepOctNovDec236191165236392346204904049128244
Rainfall (mm)Rain days
Jan23626
Feb19123
Mar16524
Apr23625
May39229
Jun34629
Jul20426
Aug9017
Sep4010
Oct4912
Nov12820
Dec24427

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Kourou, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around July 7 and lasts for 4.5 months, ending around November 20. The clearest month is September, when the sky is clear, mostly clear, or partly cloudy 81% of the time on average.

The cloudier part of the year begins around November 21 and lasts for 7.5 months, ending around July 6. The cloudiest month is May, when it is overcast or mostly cloudy 75% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecSep 21 · 82%May 25 · 21%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan3367
Feb3466
Mar3862
Apr3268
May2575
Jun3070
Jul5644
Aug7525
Sep8119
Oct7129
Nov4951
Dec3565

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. Close to the equator, Kourou barely changes through the year: days stay near 12 h 18 min of light in every season.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan11.76:486:32
Feb11.86:506:40
Mar12.06:416:39
Apr12.16:276:34
May12.26:206:34
Jun12.36:226:40
Jul12.36:286:44
Aug12.26:306:40
Sep12.06:246:26
Oct11.96:196:12
Nov11.86:236:09
Dec11.76:366:18

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Kourou averages about 8 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 3 and 19 days.

The sunnier stretch runs 4.3 months, from around Jul 9 to Nov 16. The sunniest month is September, with roughly 18 sunny days (bright).

The greyest month is May, down near 3 sunny days — about 84% fewer than the September peak.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightbrilliantSep 319 daysMay 213 days
Sunny daysSky
Jan4Gloomy
Feb3Gloomy
Mar4Gloomy
Apr3Gloomy
May3Gloomy
Jun4Gloomy
Jul10Mixed
Aug16Bright
Sep18Bright
Oct16Bright
Nov8Mixed
Dec4Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

Kourou is humid all year round — on a typical day the air feels at least humid, and there is no real dry season to wait for.

The stickiest month is January, when it feels muggy, oppressive or miserable about 100% of the time. Even in January, the mildest month, the air is dry or comfortable only 0% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecmiserableoppressivemuggy
Muggy (%)Oppressive (%)Miserable (%)
Jan4942
Feb7903
Mar6904
Apr28316
May07030
Jun08119
Jul0928
Aug08614
Sep07921
Oct07624
Nov07129
Dec18712

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Across the year, average wind speed in Kourou is typically light breeze, near 15 km/h, and varies moderately with the seasons.

The windier part of the year lasts 5.3 months, from around Dec 8 to May 17. The windiest month is February, averaging about 19 km/h (light breeze).

The calmer part of the year runs from around May 18 to Dec 7, with July the calmest month at about 11 km/h.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmercalmlight breezebreezyFeb 11 · 19 km/hJul 15 · 11 km/h
Wind speed (km/h)Feels
Jan17light breeze
Feb19light breeze
Mar18light breeze
Apr17light breeze
May15light breeze
Jun13light breeze
Jul11calm
Aug12light breeze
Sep14light breeze
Oct14light breeze
Nov14light breeze
Dec16light breeze

Hazard calendar for Kourou

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Kourou's rainy season runs April–July, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Best time to visit Kourou

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Kourou throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late October, Kourou is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Kourou for general outdoor tourist activities is from early August to early November, with a peak score in the third week of September.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationSep 15 · 5.5

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan4.1fair
Feb4.2fair
Mar4.3fair
Apr4.0fair
May3.6fair
Jun3.4poor
Jul3.8fair
Aug4.8fair
Sep5.5fair
Oct5.2fair
Nov4.2fair
Dec3.8fair

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Kourou for hot-weather activities is from mid August to early November, with a peak score in the last week of September.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationSep 22 · 7.3

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Kourou, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

Kourou packs about the same all year — highs hold near 30°C. Across the year the things worth having are light clothes, rain gear and sun protection.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In October, Kourou sees daytime highs around 30°C and nights near 25°C. Pack light clothes and sun protection. Worth having: rain gear. About 12 days see rain.

Sea temperature near Kourou

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea offshore is warmest in July at about 28°C and coldest in January near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr27Warm
May28Warm
Jun28Warm
Jul28Tropical
Aug28Tropical
Sep28Tropical
Oct28Tropical
Nov28Warm
Dec27Warm

UV index (midday) in Kourou by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Kourou peaks around April 11 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 11 at about 10 (extreme).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeApr 11UV 14Dec 11UV 10
UV index (midday)Level
Jan13Extreme
Feb13Extreme
Mar14Extreme
Apr14Extreme
May13Extreme
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep12Extreme
Oct12Extreme
Nov11Extreme
Dec10Extreme

Average hourly UV index in Kourou

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in April the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan86
Feb86.5
Mar86.5
Apr8.56.5
May86.5
Jun86
Jul7.55.5
Aug7.55.5
Sep86
Oct86
Nov7.55.5
Dec7.55.5

Air quality in Kourou by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Kourou is worst in February — around 28 µg/m³ PM2.5 (moderate), about 4.0× the cleanest month (August, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateFeb 1627 µg/m³Aug 157 µg/m³
PM2.5 (µg/m³)Level
Jan26Moderate
Feb28Moderate
Mar26Moderate
Apr26Moderate
May21Moderate
Jun12Moderate
Jul8Good
Aug7Good
Sep8Good
Oct10Good
Nov12Good
Dec21Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Kourou is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Kourou banks about 5,987 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around October.

02,0004,0006,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan490
Feb444
Mar499
Apr490
May504
Jun484
Jul508
Aug522
Sep512
Oct531
Nov502
Dec500

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Kourou receives about 5.2 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 4.4 and 6.3 kWh/m².

The brighter stretch of the year lasts 4.3 months, from around Jul 15 to Nov 21. The brightest month is September, averaging about 6.2 kWh/m² (intense).

The dimmest month is May, down near 4.6 kWh/m² — roughly 27% less than the September peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseSep 256.3 kWhMay 304.4 kWh
Solar energy (kWh/m²)Level
Jan4.5Bright
Feb4.8Bright
Mar5.2Bright
Apr5.1Bright
May4.5Bright
Jun4.5Bright
Jul5.2Bright
Aug5.8Bright
Sep6.3Intense
Oct6.1Intense
Nov5.3Bright
Dec4.6Bright

Where is Kourou?

Kourou sits at 5.2°N, 52.6°W, 7 m above sea level, in French Guiana. The nearest listed city is Cayenne, 42 km away.

CayenneMatouryRémire-MontjolySaint-Laurent-du-MaroniOiapoque

Topography around Kourou

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Kourou.

Within 3 km, the terrain around Kourou has only modest variations in elevation — a maximum elevation change of 67 m around an average of 4 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 165 m; within 80 km, significant variations in elevation — a maximum elevation change of 403 m.

The land around Kourou is covered by water (45%) within 3 km, water (47%) and trees (34%) within 16 km, and trees (57%) and water (37%) within 80 km.

3 km
67 m
16 km
165 m
80 km
403 m
treesgrasslandartificial surfaceswaterwetlandmangroves
Nearby: Cayenne 42 km · Matoury 50 km · Rémire-Montjoly 50 km · Saint-Laurent-du-Maroni 158 km · Oiapoque 172 km · Blauwgrond 284 km · Rainville 286 km · Beekhuizen 289 km

French Guiana travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / E
220 V · 50 Hz

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 Kourou (5.1628°, -52.6427°, elevation 7 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).