Cesson-Sévigné weather in September

In September, Cesson-Sévigné sees average daytime highs of 21°C and overnight lows near 11°C, with 50 mm of rain across 8.2 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 22°C in the first days to 19°C by the end. The sky is clear or mostly clear about 23% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 12 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Cesson-Sévigné's 2nd-clearest and 10th-windiest month. For the whole year in context, see Cesson-Sévigné's year-round climate.

Daytime high
21°
4th warmest
Overnight low
11°
9th coldest
Rainfall
50 mm
8.2 wet days
Daylight
12 h 18 min
6:50 AM – 7:11 PM
Cloud cover
62%
2nd clearest
Wind
12 km/h
10th windiest
Solar energy
3.65 kWh/m²
Travel score
6.5
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 22°C in the first days to 19°C by the end.

A typical September day in Cesson-Sévigné reaches about 21°C in the afternoon and slips back to 11°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 25°C. Set against its neighbours, September runs about 3°C cooler than August and about 4°C warmer than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12213
22213
32212
42212
52212
62212
72212
82212
92112
102112
112112
122112
132112
142111
152111
162111
172011
182011
192011
202011
212011
222011
232011
242011
251911
261911
271911
281911
291910
301910

How September really feels in Cesson-Sévigné

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

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

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Cesson-Sévigné weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 6811.40.58.61.4
Feb / 559.80.59.91.8
Mar12° / 5410.70.211.63.2
Apr15° / 5811013.44.3
May18° / 6410.9014.95.6
Jun21° / 12°548.9015.86.5
Jul23° / 14°488.2015.47.1
Aug23° / 14°488.4014.17.1
Sep21° / 11°508.2012.46.5
Oct16° / 7111.4010.64.8
Nov12° / 6711.5092.8
Dec / 7512.10.48.21.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 59%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14456
24456
34456
44456
54456
64456
74456
84357
94357
104258
114258
124258
134159
144159
154159
164159
174159
184060
194060
204060
214060
223961
233961
243862
253862
263565
273565
283466
293268
303268

Chance of precipitation in September

Any precipitation

Cesson-Sévigné gets around 50 mm of rain over 8.2 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 28% and peaks near 37% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
121
221
321
421
521
622
722
823
923
1024
1125
1226
1326
1427
1528
1629
1729
1830
1931
2031
2132
2232
2333
2434
2535
2635
2736
2836
2937
3037

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 65% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
15533111
25633101
35732101
4583291
5583291
6603181
7603181
8613180
9613180
10633070
11633070
12642970
13642970
14662860
15662860
16672760
17672760
18692650
19692650
20692650
21692650
22702640
23702640
24702640
25702640
26702640
27702640
28712540
29712540
30712540

Wind in September

Winds average 12 km/h in September.

Across September, daily wind ranges from about 12 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
112calm
212calm
312calm
412calm
512calm
612calm
712calm
812calm
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2813light breeze
2913light breeze
3013light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 12 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 102 minutes over September. Sunrise moves from 6:29 AM to 7:11 AM, and sunset from 7:43 PM to 6:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.26:297:43
213.26:317:41
313.16:327:39
413.16:337:37
513.06:357:35
612.96:367:33
712.96:387:30
812.86:397:28
912.86:407:26
1012.76:427:24
1112.66:437:22
1212.66:457:20
1312.56:467:18
1412.56:487:15
1512.46:497:13
1612.36:507:11
1712.36:527:09
1812.26:537:07
1912.26:557:05
2012.16:567:02
2112.06:587:00
2212.06:596:58
2311.97:006:56
2411.97:026:54
2511.87:036:52
2611.77:056:49
2711.77:066:47
2811.67:086:45
2911.67:096:43
3011.57:116:41

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.65 kWh/m².

For context, solar energy here swings from a low near 0.9 kWh/m² to a high of 5.73 kWh/m² in June across the year — September's 3.65 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.3Bright
24.3Bright
34.2Bright
44.2Bright
54.2Bright
64.1Bright
74.1Bright
84.0Bright
94.0Moderate
103.9Moderate
113.9Moderate
123.8Moderate
133.8Moderate
143.7Moderate
153.7Moderate
163.6Moderate
173.6Moderate
183.5Moderate
193.5Moderate
203.4Moderate
213.4Moderate
223.3Moderate
233.2Moderate
243.2Moderate
253.1Moderate
263.1Moderate
273.0Moderate
282.9Moderate
292.9Moderate
302.8Moderate
Planning a trip in September

Is September a good time to visit Cesson-Sévigné?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.5
Sightseeing
3rd-best month of the year
3.8
Beach & pool
4th-best month of the year

September is a reasonable time to visit Cesson-Sévigné for sightseeing.

What to pack for Cesson-Sévigné in September

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

In September, Cesson-Sévigné sees daytime highs around 21°C and nights near 11°C. Worth packing: rain gear. About 8 days see rain.

rain gear

Sea temperature near Cesson-Sévigné in September

The nearest coast averages about 18°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 56 km away) is warmest in August at about 19°C and coldest in February near 8°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan9Bracing
Feb8Bracing
Mar8Bracing
Apr10Bracing
May13Bracing
Jun16Cool
Jul18Cool
Aug19Cool
Sep18Cool
Oct16Cool
Nov13Bracing
Dec10Bracing

UV index in Cesson-Sévigné in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Cesson-Sévigné peaks around June 18 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 18UV 7Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr5High
May6High
Jun7High
Jul6High
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Cesson-Sévigné?

Cesson-Sévigné sits at 48.1°N, 1.6°W, 37 m above sea level, in France. The nearest listed city is Rennes, 5.0 km away.

Topography around Cesson-Sévigné

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

Within 3 km, the terrain around Cesson-Sévigné has only modest variations in elevation — a maximum elevation change of 69 m around an average of 48 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 125 m; within 80 km, significant variations in elevation — a maximum elevation change of 353 m.

The land around Cesson-Sévigné is covered by trees (29%), grassland (25%) and artificial surfaces (25%) within 3 km, cropland (33%), grassland (28%) and trees (27%) within 16 km, and cropland (44%), grassland (28%) and trees (21%) within 80 km.

3 km
69 m
16 km
125 m
80 km
353 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Rennes 5.0 km · Vitré 29 km · Fougères 39 km · Laval 62 km · Saint-Malo 66 km · Mayenne 76 km · La Chapelle-sur-Erdre 91 km · Carquefou 92 km

France travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / E
230 V · 50 Hz
Prices
≈ 77% of US
price level, 2025
GDP per capita
$48,986
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1.3
per 100k, 2023
Road deaths
5.1
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 539
Religion
Roman Catholic 47%none 33%Muslim 4%Protestant 2%

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 Cesson-Sévigné (48.1212°, -1.603°, elevation 37 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).