Cwmbran weather in September

In September, Cwmbran sees average daytime highs of 17°C and overnight lows near 10°C, with 63 mm of rain across 9.9 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 18°C in the first days to 16°C by the end. The sky is clear or mostly clear about 12% 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 Cwmbran's 6th-clearest and 9th-windiest month. For the whole year in context, see Cwmbran's year-round climate.

Daytime high
17°
4th warmest
Overnight low
10°
9th coldest
Rainfall
63 mm
9.9 wet days
Daylight
12 h 24 min
5:55 AM – 6:18 PM
Cloud cover
72%
6th clearest
Wind
13 km/h
9th windiest
Solar energy
2.97 kWh/m²
Travel score
5.3
out of 10

Cwmbran is new town in south east Wales, United Kingdom.

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 18°C in the first days to 16°C by the end.

A typical September day in Cwmbran reaches about 17°C in the afternoon and slips back to 10°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 14°C and 20°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)
11911
21811
31811
41811
51811
61811
71811
81811
91810
101810
111810
121810
131710
141710
151710
161710
171710
181710
191710
201710
211710
221710
231610
24169
25169
26169
27169
28169
29169
30169

How September really feels in Cwmbran

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.

Cwmbran 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 / 7913.21.38.10.8
Feb / 6210.51.29.61.0
Mar10° / 6311.20.811.51.9
Apr12° / 6812.10.413.63.1
May15° / 7512.7015.34.2
Jun18° / 10°7011016.35.4
Jul20° / 12°6712015.95.9
Aug20° / 12°7411.4014.45.8
Sep17° / 10°639.9012.45.3
Oct14° / 9012.70.110.43.5
Nov10° / 8413.30.48.62.0
Dec / 8712.51.17.71.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 12% 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 73%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12971
22971
32872
42872
52872
62872
72872
82773
92773
102773
112872
122872
132872
142773
152773
162773
172674
182674
192674
202674
212575
222575
232575
242476
252575
262575
272575
282575
292575
302575

Chance of precipitation in September

Any precipitation

Cwmbran gets around 63 mm of rain over 9.9 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 33% 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 (%)
130
230
329
429
530
630
730
830
931
1031
1131
1231
1332
1432
1532
1633
1733
1833
1933
2034
2134
2235
2335
2436
2537
2638
2738
2839
2939
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 80% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
173252
274242
374242
475232
575232
676222
776222
876222
977212
1077212
1178202
1278202
1379192
1479192
1580191
1681181
1781181
1881181
1981181
2082180
2183170
2283170
2383170
2483170
2584160
2684160
2785150
2886140
2986140
3087130

Wind in September

Winds average 13 km/h in September.

Across September, daily wind ranges from about 12 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
112light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2513light 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 5:30 AM to 6:18 AM, and sunset from 6:54 PM to 5:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.45:306:54
213.35:316:51
313.35:336:49
413.25:356:47
513.15:366:44
613.15:386:42
713.05:406:40
812.95:416:37
912.95:436:35
1012.85:456:33
1112.75:466:30
1212.75:486:28
1312.65:506:25
1412.55:516:23
1512.55:536:21
1612.45:556:18
1712.35:566:16
1812.35:586:13
1912.26:006:11
2012.16:016:08
2112.16:036:06
2212.06:056:04
2311.96:066:01
2411.86:085:59
2511.86:105:56
2611.76:115:54
2711.66:135:52
2811.66:155:49
2911.56:175:47
3011.46:185:45

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 2.97 kWh/m².

For context, solar energy here swings from a low near 0.63 kWh/m² to a high of 5.18 kWh/m² in June across the year — September's 2.97 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.6Moderate
23.5Moderate
33.5Moderate
43.5Moderate
53.4Moderate
63.4Moderate
73.4Moderate
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
292.3Moderate
302.3Moderate
Planning a trip in September

Is September a good time to visit Cwmbran?

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

5.3
Sightseeing
4th-best month of the year
1.3
Beach & pool
4th-best month of the year

September is a reasonable time to visit Cwmbran for sightseeing.

What to pack for Cwmbran in September

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

In September, Cwmbran sees daytime highs around 17°C and nights near 10°C. Worth packing: rain gear. About 10 days see rain.

rain gear

Sea temperature near Cwmbran 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 at the nearest coast (about 32 km away) 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
Mar8Bracing
Apr9Bracing
May12Bracing
Jun15Cool
Jul17Cool
Aug18Cool
Sep17Cool
Oct15Bracing
Nov12Bracing
Dec9Bracing

UV index in Cwmbran 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 Cwmbran peaks around August 13 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 13UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun6High
Jul6High
Aug7High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Cwmbran?

Cwmbran sits at 51.7°N, 3.0°W, 66 m above sea level, in United Kingdom. The nearest listed city is Pontypool, 5.0 km away.

Topography around Cwmbran

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

Within 3 km, the terrain around Cwmbran has significant variations in elevation — a maximum elevation change of 422 m around an average of 114 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 576 m; within 80 km, large variations in elevation — a maximum elevation change of 864 m.

The land around Cwmbran is covered by trees (40%), grassland (35%) and artificial surfaces (23%) within 3 km, grassland (48%) and trees (34%) within 16 km, and grassland (52%) within 80 km.

3 km
422 m
16 km
576 m
80 km
864 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Pontypool 5.0 km · Risca 7.0 km · Newport 8.0 km · Blackwood 13 km · Gelligaer 16 km · Caerphilly 16 km · Ebbw Vale 19 km · Cardiff 22 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 Cwmbran (51.6545°, -3.0228°, elevation 66 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).