Climate and average weather in Saint-Louis
In Saint-Louis, the weather is muggy, hot, fairly dry, and mostly clear and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around August.
Over the course of the year, the temperature in Saint-Louis typically varies from 19°C to 30°C, and is rarely below 17°C or above 33°C. October is the hottest month of the year, while April is the coldest.
Based on the travel score, the best times of year to visit Saint-Louis for warm-weather activities are from early January to late July and late November to late December.
- Hottest
- Oct
- 30°
- Coldest
- Apr
- 20°
- Wettest
- Aug
- 57 mm
- Driest
- May
- 0 mm
- Rain / yr
- 140 mm
- 20 wet days
- Daylight
- 11.0–13.0 h
- shortest–longest
- Elevation
- 8 m
- 16.0°N
- Clearest
- May
- 22% cloud
Saint-Louis is city and regional capital in Senegal.
- Founded
- 1659
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Saint-Louis 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 January to late July.
Temperature through the year
Daily average highs and lows in Saint-Louis, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
Temperatures in Saint-Louis 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 26°C; the coolest is April, with an average low of 20°C and high of 25°C.
Days typically run about 5°C warmer than nights, with the widest day–night swing (around 6°C) in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 25 | 25 | 25 | 25 | 25 | 27 | 28 | 29 | 30 | 30 | 29 | 27 |
| Avg low (°C) | 19 | 19 | 20 | 20 | 21 | 23 | 25 | 26 | 27 | 26 | 24 | 21 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 25 | 19 |
| Feb | 25 | 19 |
| Mar | 25 | 20 |
| Apr | 25 | 20 |
| May | 25 | 21 |
| Jun | 27 | 23 |
| Jul | 28 | 25 |
| Aug | 29 | 26 |
| Sep | 30 | 27 |
| Oct | 30 | 26 |
| Nov | 29 | 24 |
| Dec | 27 | 21 |
How hot and cold Saint-Louis really feels
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, Saint-Louis feels like about 36°C (around September 25). About 92 days a year carry some heat stress, peaking in September.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 25 | 25 | 25 | 25 | 25 | 27 | 31 | 34 | 36 | 34 | 29 | 27 |
| Air high (°C) | 25 | 25 | 25 | 25 | 25 | 27 | 28 | 29 | 30 | 30 | 29 | 27 |
| Feels-like low (°C) | 19 | 19 | 20 | 20 | 21 | 23 | 25 | 26 | 27 | 26 | 24 | 21 |
| Air low (°C) | 19 | 19 | 20 | 20 | 21 | 23 | 25 | 26 | 27 | 26 | 24 | 21 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 25 | 25 | 19 | 19 |
| Feb | 25 | 25 | 19 | 19 |
| Mar | 25 | 25 | 20 | 20 |
| Apr | 25 | 25 | 20 | 20 |
| May | 25 | 25 | 21 | 21 |
| Jun | 27 | 27 | 23 | 23 |
| Jul | 31 | 28 | 25 | 25 |
| Aug | 34 | 29 | 26 | 26 |
| Sep | 36 | 30 | 27 | 27 |
| Oct | 34 | 30 | 26 | 26 |
| Nov | 29 | 29 | 24 | 24 |
| Dec | 27 | 27 | 21 | 21 |
Average hourly temperature in Saint-Louis
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 April, near 20°C.
Saint-Louis weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 25° / 19° | 3 | 0.2 | 11.2 | 8.7 |
| Feb | 25° / 19° | 1 | 0.2 | 11.5 | 8.8 |
| Mar | 25° / 20° | 0 | 0 | 11.9 | 9.1 |
| Apr | 25° / 20° | 0 | 0 | 12.3 | 9.2 |
| May | 25° / 21° | 0 | 0 | 12.7 | 9.1 |
| Jun | 27° / 23° | 1 | 0.3 | 12.9 | 8.7 |
| Jul | 28° / 25° | 11 | 2 | 12.9 | 7.6 |
| Aug | 29° / 26° | 57 | 7.8 | 12.5 | 5.9 |
| Sep | 30° / 27° | 52 | 7.2 | 12.1 | 5.6 |
| Oct | 30° / 26° | 13 | 2.1 | 11.6 | 6.1 |
| Nov | 29° / 24° | 0 | 0.1 | 11.3 | 6.8 |
| Dec | 27° / 21° | 2 | 0.3 | 11.1 | 8.2 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Saint-Louis gets about 140 mm of precipitation a year. On a typical day the chance of rain is mostly dry, but that rises and falls sharply with the seasons.
The wetter season lasts 3.2 months, from around Jul 16 to Oct 20, peaking in August at about 31% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 25.
August is the wettest month by volume, with 57 mm over about 8 wet days; May is the driest, with 0 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 0 | 1 | 0 | 0 | 0 | 1 | 7 | 25 | 23 | 7 | 0 | 1 |
| Rain days | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 8 | 7 | 2 | 0 | 0 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 1 | 0 |
| Mar | 0 | 0 |
| Apr | 0 | 0 |
| May | 0 | 0 |
| Jun | 1 | 0 |
| Jul | 7 | 2 |
| Aug | 25 | 8 |
| Sep | 23 | 7 |
| Oct | 7 | 2 |
| Nov | 0 | 0 |
| Dec | 1 | 0 |
Monthly rainfall
Over a full year, Saint-Louis collects about 140 mm of rain across 20 wet days — roughly 12 mm in an average month.
It doesn’t fall evenly. August is the wettest month with 57 mm, while May is the driest at just 0 mm. The three wettest months alone bring about 87% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 3 | 1 | 0 | 0 | 0 | 1 | 11 | 57 | 52 | 13 | 0 | 2 |
| Rain days | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 8 | 7 | 2 | 0 | 0 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 3 | 0 |
| Feb | 1 | 0 |
| Mar | 0 | 0 |
| Apr | 0 | 0 |
| May | 0 | 0 |
| Jun | 1 | 0 |
| Jul | 11 | 2 |
| Aug | 57 | 8 |
| Sep | 52 | 7 |
| Oct | 13 | 2 |
| Nov | 0 | 0 |
| Dec | 2 | 0 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Saint-Louis, 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 February 19 and lasts for 4.9 months, ending around July 18. The clearest month is May, when the sky is clear, mostly clear, or partly cloudy 87% of the time on average.
The cloudier part of the year begins around July 19 and lasts for 2.5 months, ending around October 2. The cloudiest month is August, when it is overcast or mostly cloudy 47% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 64 | 70 | 81 | 86 | 87 | 85 | 72 | 53 | 58 | 71 | 60 | 59 |
| Cloudier (%) | 36 | 30 | 19 | 14 | 13 | 15 | 28 | 47 | 42 | 29 | 40 | 41 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 64 | 36 |
| Feb | 70 | 30 |
| Mar | 81 | 19 |
| Apr | 86 | 14 |
| May | 87 | 13 |
| Jun | 85 | 15 |
| Jul | 72 | 28 |
| Aug | 53 | 47 |
| Sep | 58 | 42 |
| Oct | 71 | 29 |
| Nov | 60 | 40 |
| Dec | 59 | 41 |
Daylight, sunrise and sunset
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. The longest day, around June 18, brings about 13 hours of light; the shortest, around December 18, only 11 hours — a swing of roughly 2 hours.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 11.2 | 11.5 | 11.9 | 12.3 | 12.7 | 12.9 | 12.9 | 12.5 | 12.1 | 11.6 | 11.3 | 11.1 |
| Sunrise (AM) | 7:41 | 7:37 | 7:19 | 6:55 | 6:40 | 6:38 | 6:46 | 6:54 | 6:58 | 7:02 | 7:14 | 7:31 |
| Sunset (PM) | 6:50 | 7:05 | 7:12 | 7:17 | 7:25 | 7:35 | 7:38 | 7:26 | 7:03 | 6:40 | 6:28 | 6:34 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 11.2 | 7:41 | 6:50 |
| Feb | 11.5 | 7:37 | 7:05 |
| Mar | 11.9 | 7:19 | 7:12 |
| Apr | 12.3 | 6:55 | 7:17 |
| May | 12.7 | 6:40 | 7:25 |
| Jun | 12.9 | 6:38 | 7:35 |
| Jul | 12.9 | 6:46 | 7:38 |
| Aug | 12.5 | 6:54 | 7:26 |
| Sep | 12.1 | 6:58 | 7:03 |
| Oct | 11.6 | 7:02 | 6:40 |
| Nov | 11.3 | 7:14 | 6:28 |
| Dec | 11.1 | 7:31 | 6:34 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Saint-Louis averages about 17 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 8 and 24 days.
The sunnier stretch runs 4.8 months, from around Feb 16 to Jul 12. The sunniest month is May, with roughly 24 sunny days (brilliant).
The greyest month is August, down near 10 sunny days — about 60% fewer than the May peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 16 | 17 | 22 | 23 | 24 | 22 | 17 | 10 | 13 | 18 | 14 | 14 |
| Sky | Bright | Bright | Bright | Brilliant | Brilliant | Bright | Bright | Mixed | Mixed | Bright | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 16 | Bright |
| Feb | 17 | Bright |
| Mar | 22 | Bright |
| Apr | 23 | Brilliant |
| May | 24 | Brilliant |
| Jun | 22 | Bright |
| Jul | 17 | Bright |
| Aug | 10 | Mixed |
| Sep | 13 | Mixed |
| Oct | 18 | Bright |
| Nov | 14 | Mixed |
| Dec | 14 | Mixed |
Humidity comfort
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.
In Saint-Louis, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 6.5 months, from around April 26 to November 10. The muggiest month is June, when the air feels humid, muggy or worse about 99% of the time.
The most comfortable stretch runs from around November 11 to April 25, and January is the most comfortable month — the air is dry or comfortable 93% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 79 | 65 | 38 | 9 | 2 | 0 | 0 | 0 | 0 | 1 | 21 | 61 |
| Comfortable (%) | 15 | 23 | 37 | 36 | 12 | 1 | 0 | 0 | 0 | 3 | 21 | 18 |
| Humid (%) | 6 | 11 | 24 | 52 | 54 | 8 | 0 | 0 | 0 | 6 | 24 | 12 |
| Muggy (%) | 0 | 1 | 1 | 2 | 29 | 42 | 7 | 1 | 1 | 19 | 26 | 8 |
| Oppressive (%) | 0 | 0 | 0 | 0 | 3 | 49 | 78 | 44 | 24 | 40 | 8 | 0 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 15 | 55 | 75 | 31 | 1 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| Jan | 79 | 15 | 6 | 0 | 0 | 0 |
| Feb | 65 | 23 | 11 | 1 | 0 | 0 |
| Mar | 38 | 37 | 24 | 1 | 0 | 0 |
| Apr | 9 | 36 | 52 | 2 | 0 | 0 |
| May | 2 | 12 | 54 | 29 | 3 | 0 |
| Jun | 0 | 1 | 8 | 42 | 49 | 0 |
| Jul | 0 | 0 | 0 | 7 | 78 | 15 |
| Aug | 0 | 0 | 0 | 1 | 44 | 55 |
| Sep | 0 | 0 | 0 | 1 | 24 | 75 |
| Oct | 1 | 3 | 6 | 19 | 40 | 31 |
| Nov | 21 | 21 | 24 | 26 | 8 | 1 |
| Dec | 61 | 18 | 12 | 8 | 0 | 0 |
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 Saint-Louis is typically light breeze, near 20 km/h, and varies moderately with the seasons.
The windier part of the year lasts 5.5 months, from around Dec 22 to Jun 5. The windiest month is April, averaging about 24 km/h (breezy).
The calmer part of the year runs from around Jun 6 to Dec 21, with September the calmest month at about 16 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 21 | 22 | 23 | 24 | 22 | 20 | 19 | 17 | 16 | 18 | 19 | 20 |
| Feels | breezy | breezy | breezy | breezy | breezy | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 21 | breezy |
| Feb | 22 | breezy |
| Mar | 23 | breezy |
| Apr | 24 | breezy |
| May | 22 | breezy |
| Jun | 20 | light breeze |
| Jul | 19 | light breeze |
| Aug | 17 | light breeze |
| Sep | 16 | light breeze |
| Oct | 18 | light breeze |
| Nov | 19 | light breeze |
| Dec | 20 | light breeze |
Hazard calendar for Saint-Louis
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Saint-Louis sits in the Atlantic hurricane belt; the season peaks August–October.
Saint-Louis sees dust haze year-round, heaviest in June.
Best time to visit Saint-Louis
To characterize how pleasant the weather is in Saint-Louis throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around mid July, Saint-Louis 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 Saint-Louis for general outdoor tourist activities is from late November to late July, with a peak score in the first week of May.
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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 8.7 | 8.8 | 9.1 | 9.2 | 9.1 | 8.7 | 7.6 | 5.9 | 5.6 | 6.1 | 6.8 | 8.2 |
| Rating | ideal | ideal | ideal | ideal | ideal | ideal | ideal | good | good | good | good | ideal |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 8.7 | ideal |
| Feb | 8.8 | ideal |
| Mar | 9.1 | ideal |
| Apr | 9.2 | ideal |
| May | 9.1 | ideal |
| Jun | 8.7 | ideal |
| Jul | 7.6 | ideal |
| Aug | 5.9 | good |
| Sep | 5.6 | good |
| Oct | 6.1 | good |
| Nov | 6.8 | good |
| Dec | 8.2 | ideal |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, Saint-Louis suits hot-weather activities for most of the year, with a peak score in the third week of November.
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 Saint-Louis, by month
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.
Saint-Louis packs about the same all year — highs hold near 30°C. Across the year the things worth having are light clothes, sun protection and a windbreaker.
In October, Saint-Louis sees daytime highs around 30°C and nights near 26°C. Pack light clothes and sun protection.
Sea temperature near Saint-Louis
Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.
The sea at the nearest coast (about 19 km away) is warmest in September at about 28°C and coldest in February near 19°C.
It's comfortable for a long swim from May 3 to Jan 11 — about 8.4 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 20 | 19 | 19 | 19 | 21 | 24 | 26 | 28 | 28 | 28 | 25 | 22 |
| Comfort | Cool | Cool | Cool | Cool | Refreshing | Refreshing | Warm | Warm | Tropical | Warm | Warm | Refreshing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 20 | Cool |
| Feb | 19 | Cool |
| Mar | 19 | Cool |
| Apr | 19 | Cool |
| May | 21 | Refreshing |
| Jun | 24 | Refreshing |
| Jul | 26 | Warm |
| Aug | 28 | Warm |
| Sep | 28 | Tropical |
| Oct | 28 | Warm |
| Nov | 25 | Warm |
| Dec | 22 | Refreshing |
UV index (midday) in Saint-Louis by month
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 Saint-Louis peaks around March 18 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 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) | 8 | 11 | 13 | 11 | 12 | 10 | 10 | 11 | 11 | 9 | 8 | 7 |
| Level | Very high | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Extreme | Extreme | Very high | Very high | High |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 8 | Very high |
| Feb | 11 | Extreme |
| Mar | 13 | Extreme |
| Apr | 11 | Extreme |
| May | 12 | Extreme |
| Jun | 10 | Extreme |
| Jul | 10 | Very high |
| Aug | 11 | Extreme |
| Sep | 11 | Extreme |
| Oct | 9 | Very high |
| Nov | 8 | Very high |
| Dec | 7 | High |
Average hourly UV index in Saint-Louis
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 March the burn window is concentrated in the middle of the day: about 8 hours a day reach index 3 (protection recommended), and 6 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 6.5 | 7 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 7 | 6.5 | 6 |
| UV ≥ 6 (h/day) | 4 | 5 | 6 | 5.5 | 6 | 5.5 | 5.5 | 5.5 | 5.5 | 4.5 | 3.5 | 3 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 6.5 | 4 |
| Feb | 7 | 5 |
| Mar | 8 | 6 |
| Apr | 8 | 5.5 |
| May | 8 | 6 |
| Jun | 8 | 5.5 |
| Jul | 8 | 5.5 |
| Aug | 8 | 5.5 |
| Sep | 8 | 5.5 |
| Oct | 7 | 4.5 |
| Nov | 6.5 | 3.5 |
| Dec | 6 | 3 |
Air quality in Saint-Louis by month
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 Saint-Louis is worst in January — around 99 µg/m³ PM2.5 (unhealthy), about 3.3× the cleanest month (August, 30 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) | 99 | 97 | 70 | 50 | 46 | 61 | 42 | 30 | 35 | 51 | 54 | 90 |
| Level | Unhealthy | Unhealthy | Unhealthy | Poor | Poor | Unhealthy | Poor | Moderate | Moderate | Poor | Poor | Unhealthy |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 99 | Unhealthy |
| Feb | 97 | Unhealthy |
| Mar | 70 | Unhealthy |
| Apr | 50 | Poor |
| May | 46 | Poor |
| Jun | 61 | Unhealthy |
| Jul | 42 | Poor |
| Aug | 30 | Moderate |
| Sep | 35 | Moderate |
| Oct | 51 | Poor |
| Nov | 54 | Poor |
| Dec | 90 | Unhealthy |
Growing season
Saint-Louis is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
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. Saint-Louis banks about 5,402 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around October.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 375 | 340 | 382 | 364 | 407 | 450 | 513 | 543 | 543 | 563 | 493 | 430 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 375 |
| Feb | 340 |
| Mar | 382 |
| Apr | 364 |
| May | 407 |
| Jun | 450 |
| Jul | 513 |
| Aug | 543 |
| Sep | 543 |
| Oct | 563 |
| Nov | 493 |
| Dec | 430 |
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.
Saint-Louis receives about 6.3 kWh/m² a day of solar energy on average — intense — with a clear seasonal swing between 5.0 and 7.4 kWh/m².
The brighter stretch of the year lasts 5.2 months, from around Feb 24 to Aug 1. The brightest month is May, averaging about 7.4 kWh/m² (intense).
The dimmest month is December, down near 5.0 kWh/m² — roughly 32% less than the May peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 5.3 | 5.9 | 6.9 | 7.3 | 7.4 | 7.1 | 6.6 | 6.0 | 6.1 | 6.1 | 5.5 | 5.0 |
| Level | Bright | Bright | Intense | Intense | Intense | Intense | Intense | Bright | Intense | Intense | Bright | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 5.3 | Bright |
| Feb | 5.9 | Bright |
| Mar | 6.9 | Intense |
| Apr | 7.3 | Intense |
| May | 7.4 | Intense |
| Jun | 7.1 | Intense |
| Jul | 6.6 | Intense |
| Aug | 6.0 | Bright |
| Sep | 6.1 | Intense |
| Oct | 6.1 | Intense |
| Nov | 5.5 | Bright |
| Dec | 5.0 | Bright |
Where is Saint-Louis?
Saint-Louis sits at 16.0°N, 16.5°W, 8 m above sea level, in Senegal. The nearest listed city is Louga, 53 km away.
What Saint-Louis looks like
Topography around Saint-Louis
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Saint-Louis.
Within 3 km, the terrain around Saint-Louis has only modest variations in elevation — a maximum elevation change of 9 m around an average of 1 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 26 m; within 80 km, only modest variations in elevation — a maximum elevation change of 57 m.
The land around Saint-Louis is covered by water (34%), artificial surfaces (27%) and wetland (22%) within 3 km, water (47%) and grassland (26%) within 16 km, and grassland (39%) and water (35%) within 80 km.
Senegal travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type C / D / E / K
- 230 V · 50 Hz
- Prices
- ≈ 36% of US
- price level, 2025
- GDP per capita
- $1,955
- 2025
- Happiness
- 4.8 / 10
- World Happiness, 2025
- Safe drinking water
- 27%
- of population, 2024
- Homicide rate
- 0.3
- per 100k, 2015
- Road deaths
- 23.5
- per 100k/yr, 2019
- Income group
- Lower middle
- World Bank
- English
- Very low
- EF EPI 442
- 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 Saint-Louis (16.0179°, -16.4896°, elevation 8 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).