Nailsea weather in September

In September, Nailsea sees average daytime highs of 18°C and overnight lows near 11°C, with 57 mm of rain across 9.4 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 19°C in the first days to 16°C by the end. The sky is clear or mostly clear about 13% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 24 min at the start of September to 11 h 24 min by month's end. Set against the rest of the year, September is Nailsea's 6th-clearest and 9th-windiest month. For the whole year in context, see Nailsea's year-round climate.

Daytime high
18°
4th warmest
Overnight low
11°
9th coldest
Rainfall
57 mm
9.4 wet days
Daylight
12 h 24 min
5:54 AM – 6:17 PM
Cloud cover
71%
6th clearest
Wind
14 km/h
9th windiest
Solar energy
2.96 kWh/m²
Travel score
5.6
out of 10

Nailsea is town in North Somerset, England.

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 19°C in the first days to 16°C by the end.

A typical September day in Nailsea reaches about 18°C in the afternoon and slips back to 11°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 21°C. Set against its neighbours, September runs about 2°C cooler than August and about 4°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
11912
21912
31912
41912
51912
61911
71911
81911
91911
101911
111811
121811
131811
141811
151811
161811
171811
181811
191810
201710
211710
221710
231710
241710
251710
261710
271710
281710
291610
301610

How September really feels in Nailsea

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.

Nailsea 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 / 72130.88.11.1
Feb / 5710.50.89.61.3
Mar10° / 5710.80.511.52.3
Apr13° / 6311.60.113.53.4
May16° / 6711.7015.34.7
Jun19° / 11°6210.7016.35.7
Jul21° / 13°6110.7015.96.2
Aug20° / 13°7110.8014.46.1
Sep18° / 11°579.4012.45.6
Oct14° / 7912.3010.43.8
Nov11° / 7713.20.18.62.2
Dec / 7912.20.57.71.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 13% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 72%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13268
23169
33169
43070
53070
63070
72971
82971
93070
103070
112971
122872
132773
142773
152773
162773
172872
182872
192872
202872
212773
222773
232773
242773
252872
262773
272773
282872
292872
302872

Chance of precipitation in September

Any precipitation

Nailsea gets around 57 mm of rain over 9.4 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 31% and peaks near 39% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
128
227
327
427
527
628
728
828
928
1029
1129
1229
1330
1430
1530
1631
1731
1831
1932
2032
2133
2234
2334
2435
2536
2637
2737
2838
2938
3039

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 74% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
165314
265314
366304
467294
568284
668284
769274
870264
971263
1072253
1173243
1273243
1374233
1474233
1576222
1676222
1776222
1877221
1977221
2076231
2176231
2276231
2376231
2476231
2577221
2677221
2778211
2879201
2980191
3081181

Wind in September

Winds average 14 km/h in September.

Across September, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 24 min at the start of September to 11 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 120 minutes over September. Sunrise moves from 5:29 AM to 6:17 AM, and sunset from 6:52 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.45:296:52
213.35:316:50
313.35:326:48
413.25:346:45
513.15:366:43
613.15:376:41
713.05:396:38
812.95:416:36
912.95:426:34
1012.85:446:31
1112.75:466:29
1212.75:476:27
1312.65:496:24
1412.55:506:22
1512.55:526:19
1612.45:546:17
1712.35:556:15
1812.35:576:12
1912.25:596:10
2012.16:006:07
2112.16:026:05
2212.06:046:03
2311.96:056:00
2411.86:075:58
2511.86:095:55
2611.76:105:53
2711.66:125:51
2811.66:145:48
2911.56:155:46
3011.46:175:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.96 kWh/m².

For context, solar energy here swings from a low near 0.64 kWh/m² to a high of 5.14 kWh/m² in June across the year — September's 2.96 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.5Moderate
23.5Moderate
33.5Moderate
43.5Moderate
53.4Moderate
63.4Moderate
73.3Moderate
83.3Moderate
93.3Moderate
103.2Moderate
113.2Moderate
123.1Moderate
133.1Moderate
143.0Moderate
153.0Moderate
163.0Moderate
172.9Moderate
182.9Moderate
192.8Moderate
202.8Moderate
212.7Moderate
222.7Moderate
232.6Moderate
242.6Moderate
252.5Moderate
262.5Moderate
272.4Moderate
282.4Moderate
292.4Moderate
302.3Moderate
Planning a trip in September

Is September a good time to visit Nailsea?

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

5.6
Sightseeing
4th-best month of the year
1.9
Beach & pool
4th-best month of the year

September is a reasonable time to visit Nailsea for sightseeing.

What to pack for Nailsea in September

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

In September, Nailsea sees daytime highs around 18°C and nights near 11°C. Worth packing: rain gear. About 9 days see rain.

rain gear

Sea temperature near Nailsea in September

The nearest coast averages about 17°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 18°C and coldest in February near 7°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
Jan8Bracing
Feb7Bracing
Mar7Bracing
Apr9Bracing
May12Bracing
Jun15Cool
Jul18Cool
Aug18Cool
Sep17Cool
Oct15Bracing
Nov12Bracing
Dec9Bracing

UV index in Nailsea in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Nailsea peaks around August 12 at about 6 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowAug 12UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun6High
Jul6High
Aug7High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Nailsea?

Nailsea sits at 51.4°N, 2.8°W, 31 m above sea level, in United Kingdom. The nearest listed city is Portishead, 6.0 km away.

Topography around Nailsea

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

Within 3 km, the terrain around Nailsea has only modest variations in elevation — a maximum elevation change of 167 m around an average of 39 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 322 m; within 80 km, large variations in elevation — a maximum elevation change of 864 m.

The land around Nailsea is covered by grassland (56%) and trees (26%) within 3 km, grassland (38%) and water (29%) within 16 km, and grassland (50%) within 80 km.

3 km
167 m
16 km
322 m
80 km
864 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Portishead 6.0 km · Clevedon 7.0 km · Bristol 12 km · Kingswood 17 km · Weston-super-Mare 18 km · Keynsham 18 km · Mangotsfield 19 km · Mendip 24 km

United Kingdom travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type D / G / M
230 V · 50 Hz
Prices
≈ 89% of US
price level, 2025
GDP per capita
$57,602
2025
Happiness
6.7 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1.1
per 100k, 2021
Road deaths
3.2
per 100k/yr, 2019
Income group
High
World Bank
Religion
Christian 60%none 26%Muslim 4%other 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 Nailsea (51.4324°, -2.7585°, elevation 31 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).