Semi in Fall

In fall (September, October and November), Semi sees average daytime highs around 27°C and overnight lows near 26°C, with 263 mm of rain over about 52 wet days across the season. It is the 3rd-warmest season and the 3rd-wettest season.

Over the season highs climb from about 25°C in early September to 28°C by late November. The sky is clear or mostly clear about 26% of the time across fall, and the air most often feels oppressive.

Fall is Semi's 2nd-best season to visit on our travel score. Semi 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 Semi's year-round climate.

Avg daytime high
27°C
3rd-warmest season
Avg overnight low
26°C
Rainfall
263 mm
52 wet days
Avg wind
17 km/h
Travel score
5.3
2nd-best season
Months
Sep · Oct · Nov

Temperature in Semi in Fall

Average highAverage lowShaded bands: 10–90% of days

Over the season highs climb from about 25°C in early September to 28°C by late November.

A typical fall day in Semi reaches about 27°C and drops to 26°C overnight. The warmest of the three months is November, the coolest September.

20°23°25°28°30°SepOctNov

How fall really feels in Semi

Once humidity and wind are folded in, fall brings about 21 days that feel above 32°C and 0 that feel at or below 0°C.

Days feeling ≥ 32°C
21
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in fall is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Semi 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.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 26°216.611.77.1
Feb28° / 27°277.811.86.4
Mar29° / 27°4812.5125.3
Apr29° / 27°7315.712.14.8
May28° / 27°16423.412.34.0
Jun27° / 26°25926.112.43.9
Jul26° / 25°13218.912.35.2
Aug25° / 24°7313.312.26.1
Sep26° / 25°10518125.2
Oct27° / 26°11020.211.95.0
Nov28° / 27°4913.811.75.7
Dec28° / 27°277.611.66.9

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 26% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitation

Semi gets around 263 mm of rain over 52 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%80%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

Most of fall feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.

0%25%50%75%100%SepOctNov

Wind in Fall

Winds average 17 km/h across fall.

0510152025SepOctNov

Sunrise & sunset in Fall

DaylightNight

Daylight runs from about 12 h 06 min in early September to 11 h 42 min by late November. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMSepOctNov

Solar energy in Fall

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across fall, about 4.9 kWh/m².

0246SepOctNov
Planning a trip in fall

Hazard calendar for Semi

In seasonPeak

None of Semi's seasonal hazards peak in fall. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do.

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

Semi sees seasonal dust haze (January–April), heaviest in February.

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

Is fall a good time to visit Semi?

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.

5.3
Sightseeing
2nd-best month of the year
5.5
Beach & pool
3rd-best month of the year

fall is a reasonable time to visit Semi for sightseeing.

What to pack for Semi in Fall

From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In fall, Semi sees daytime highs around 27°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 52 days see rain.

light clothesrain gearsun protection

Sea temperature near Semi in Fall

The nearest coast averages about 27°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 May at about 29°C and coldest in August near 25°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Warm
Feb28Tropical
Mar29Tropical
Apr29Tropical
May29Tropical
Jun28Warm
Jul26Warm
Aug25Warm
Sep26Warm
Oct27Warm
Nov29Tropical
Dec28Tropical

UV index in Semi in Fall

LowModerateHighVery highExtreme

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 Semi peaks around April 10 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 8 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeExtremeVery highApr 10UV 13Dec 19UV 8
UV index (midday)Level
Jan8Very high
Feb10Very high
Mar12Extreme
Apr13Extreme
May11Extreme
Jun11Extreme
Jul11Extreme
Aug10Very high
Sep12Extreme
Oct12Extreme
Nov9Very high
Dec8Very high

Air quality in Semi in Fall

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.

Air quality in Semi is worst in January — around 78 µg/m³ PM2.5 (unhealthy), about 7.7× the cleanest month (September, 10 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyModerateGoodModerateJan 1676 µg/m³Sep 1810 µg/m³
PM2.5 (µg/m³)Level
Jan78Unhealthy
Feb61Unhealthy
Mar28Moderate
Apr24Moderate
May15Moderate
Jun15Moderate
Jul16Moderate
Aug13Moderate
Sep10Good
Oct12Good
Nov19Moderate
Dec61Unhealthy
Location & terrain

Where is Semi?

Semi sits at 6.4°N, 2.6°E, 8 m above sea level, in Benin. The nearest listed city is Ekpé, 9.0 km away.

Topography around Semi

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

Within 3 km, the terrain around Semi has only modest variations in elevation — a maximum elevation change of 13 m around an average of 3 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 30 m; within 80 km, only modest variations in elevation — a maximum elevation change of 171 m.

The land around Semi is covered by water (45%) and grassland (22%) within 3 km, water (58%) within 16 km, and water (37%) and trees (34%) within 80 km.

3 km
13 m
16 km
30 m
80 km
171 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
Fall weather nearby: Ekpé 9.0 km · Porto-Novo 15 km · Adjarra 19 km · Avrankou 21 km · Missérété 22 km · Cotonou 22 km · Ganvié 27 km · Badagry 30 km

Benin travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / E
220 V · 50 Hz
Prices
≈ 34% of US
price level, 2025
GDP per capita
$1,658
2025
Happiness
4.4 / 10
World Happiness, 2025
Safe drinking water
18%
of population, 2024
Homicide rate
1.1
per 100k, 2017
Road deaths
26.8
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Very low
EF EPI 406
Religion
Muslim 28%Roman Catholic 26%Protestant 14%Vodoun 12%

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 Semi (6.3667°, 2.6167°, 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.