Saint-Lô weather in September

In September, Saint-Lô sees average daytime highs of 19°C and overnight lows near 11°C, with 61 mm of rain across 10.4 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 11th-wettest month of the year here.

Highs ease over the month, from about 20°C in the first days to 18°C by the end. The sky is clear or mostly clear about 20% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 18 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Saint-Lô's 3rd-clearest and 9th-windiest month. For the whole year in context, see Saint-Lô's year-round climate.

Daytime high
19°
4th warmest
Overnight low
11°
9th coldest
Rainfall
61 mm
10.4 wet days
Daylight
12 h 24 min
6:48 AM – 7:09 PM
Cloud cover
64%
3rd clearest
Wind
12 km/h
9th windiest
Solar energy
3.57 kWh/m²
Travel score
5.9
out of 10
Air quality
Good
PM10 15.7 µg/m³ · 2019

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 20°C in the first days to 18°C by the end.

A typical September day in Saint-Lô reaches about 19°C in the afternoon and slips back to 11°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 23°C. Set against its neighbours, September runs about 3°C cooler than August and about 4°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
12012
22012
32012
42012
52012
62012
72012
82012
92012
102012
112011
121911
131911
141911
151911
161911
171911
181911
191911
201911
211811
221811
231811
241811
251811
261810
271810
281810
291810
301710

How September really feels in Saint-Lô

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.

Saint-Lô weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 8213.30.68.51.1
Feb / 6711.81.19.81.4
Mar11° / 65120.511.62.6
Apr14° / 6712.50.113.43.7
May17° / 7112.10155.0
Jun20° / 11°6510.7015.95.9
Jul22° / 13°5610.7015.66.5
Aug22° / 13°6711.2014.26.3
Sep19° / 11°6110.4012.45.9
Oct15° / 8013.2010.54.2
Nov11° / 8113.80.18.92.4
Dec / 9814.20.78.11.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% 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 63%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14159
24159
34258
44258
54159
64159
74060
83961
93961
103961
113961
123862
133862
143664
153763
163763
173763
183664
193664
203664
213565
223466
233466
243565
253466
263367
273268
283268
293070
303070

Chance of precipitation in September

Any precipitation

Saint-Lô gets around 61 mm of rain over 10.4 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 35% and peaks near 42% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
130
230
330
430
530
631
731
832
933
1033
1134
1234
1334
1435
1535
1635
1736
1836
1937
2037
2137
2238
2338
2439
2539
2640
2741
2841
2942
3042

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 67% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
1543781
2553681
3563581
4583570
5593470
6603370
7613270
8623260
9633160
10643060
11643060
12652960
13672850
14672850
15682750
16692650
17702640
18712540
19712540
20722530
21722530
22722530
23712630
24722620
25722620
26722620
27722620
28722620
29732520
30742510

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
612light breeze
712light breeze
812light breeze
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
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 18 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 108 minutes over September. Sunrise moves from 6:26 AM to 7:09 AM, and sunset from 7:42 PM to 6:38 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.36:267:42
213.26:277:40
313.26:297:38
413.16:307:36
513.06:327:34
613.06:337:32
712.96:357:29
812.96:367:27
912.86:387:25
1012.76:397:23
1112.76:417:21
1212.66:427:18
1312.56:447:16
1412.56:457:14
1512.46:467:12
1612.46:487:09
1712.36:497:07
1812.26:517:05
1912.26:527:03
2012.16:547:00
2112.06:556:58
2212.06:576:56
2311.96:586:54
2411.97:006:52
2511.87:016:49
2611.77:036:47
2711.77:046:45
2811.67:066:43
2911.57:086:41
3011.57:096:38

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.57 kWh/m².

For context, solar energy here swings from a low near 0.83 kWh/m² to a high of 5.84 kWh/m² in June across the year — September's 3.57 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.2Bright
24.2Bright
34.2Bright
44.1Bright
54.1Bright
64.0Bright
74.0Moderate
83.9Moderate
93.9Moderate
103.8Moderate
113.8Moderate
123.7Moderate
133.7Moderate
143.6Moderate
153.6Moderate
163.5Moderate
173.5Moderate
183.5Moderate
193.4Moderate
203.4Moderate
213.3Moderate
223.3Moderate
233.2Moderate
243.1Moderate
253.1Moderate
263.0Moderate
273.0Moderate
282.9Moderate
292.8Moderate
302.8Moderate
Planning a trip in September

Is September a good time to visit Saint-Lô?

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

5.9
Sightseeing
3rd-best month of the year
2.5
Beach & pool
4th-best month of the year

September is a reasonable time to visit Saint-Lô for sightseeing.

What to pack for Saint-Lô in September

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

In September, Saint-Lô sees daytime highs around 19°C and nights near 11°C. Worth packing: rain gear. About 10 days see rain.

rain gear

Sea temperature near Saint-Lô 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 29 km away) is warmest in August at about 18°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
May12Bracing
Jun14Bracing
Jul17Cool
Aug18Cool
Sep18Cool
Oct16Cool
Nov13Bracing
Dec11Bracing

UV index in Saint-Lô 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 Saint-Lô peaks around June 17 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 6 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 17UV 7Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr5Moderate
May6High
Jun7High
Jul6High
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Saint-Lô?

Saint-Lô sits at 49.1°N, 1.1°W, 41 m above sea level, in France. The nearest listed city is Bayeux, 33 km away.

Topography around Saint-Lô

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

Within 3 km, the terrain around Saint-Lô has only modest variations in elevation — a maximum elevation change of 131 m around an average of 72 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 218 m; within 80 km, significant variations in elevation — a maximum elevation change of 389 m.

The land around Saint-Lô is covered by grassland (36%) and trees (31%) within 3 km, grassland (50%), cropland (27%) and trees (20%) within 16 km, and water (36%), grassland (28%) and cropland (24%) within 80 km.

3 km
131 m
16 km
218 m
80 km
389 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Bayeux 33 km · Caen 54 km · Flers 57 km · Hérouville-Saint-Clair 58 km · Tourlaville 68 km · Octeville 69 km · Cherbourg 70 km · Équeurdreville-Hainneville 72 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 Saint-Lô (49.1162°, -1.0903°, elevation 41 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).