Plymouth weather in September

In September, Plymouth sees average daytime highs of 16°C and overnight lows near 14°C, with 61 mm of rain across 10.3 wet days and about 12.4 hours of daylight. It is the 3rd-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 17°C in the first days to 16°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 Plymouth's 6th-clearest and 8th-windiest month. For the whole year in context, see Plymouth's year-round climate.

Daytime high
16°
3rd warmest
Overnight low
14°
10th coldest
Rainfall
61 mm
10.3 wet days
Daylight
12 h 24 min
6:00 AM – 6:22 PM
Cloud cover
66%
6th clearest
Wind
21 km/h
8th windiest
Solar energy
3.42 kWh/m²
Travel score
5.0
out of 10

Plymouth is city in Devon, England.

Air quality
Moderate
PM2.5 11.1 µg/m³ · 2019
Density
3,282/km²
people per km²

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 17°C in the first days to 16°C by the end.

A typical September day in Plymouth reaches about 16°C in the afternoon and slips back to 14°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 18°C. Set against its neighbours, September runs about 1°C cooler than August and about 2°C warmer than October.

10°13°15°18°20°151015202530
Avg high (°C)Avg low (°C)
11715
21714
31714
41714
51714
61714
71714
81714
91714
101714
111714
121714
131714
141714
151614
161614
171614
181614
191614
201614
211613
221613
231613
241613
251613
261613
271613
281613
291613
301513

Plymouth weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan / 10215.58.31.6
Feb / 7611.99.71.5
Mar10° / 6711.911.51.9
Apr11° / 6311.513.52.6
May13° / 10°6110.815.23.6
Jun16° / 13°6110.616.14.6
Jul17° / 15°6110.515.75.6
Aug18° / 15°7011.214.35.6
Sep16° / 14°6110.312.45.0
Oct14° / 12°10414.510.53.7
Nov12° / 11215.48.82.6
Dec10° / 10915.17.92.0

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 20% of September, with mostly cloudy or overcast conditions the remaining 61%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14060
24159
34060
44060
54060
64060
73961
83961
94060
104060
113961
123961
133961
144060
154060
164060
174060
184159
194159
204159
214060
224060
234060
243961
253862
263862
273763
283763
293763
303763

Chance of precipitation in September

Any precipitation

Plymouth gets around 61 mm of rain over 10.3 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 34% and peaks near 44% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
129
229
329
429
529
630
730
830
931
1031
1131
1232
1332
1432
1533
1633
1734
1834
1935
2035
2136
2237
2338
2439
2540
2641
2742
2843
2943
3044

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 58% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
145478
246468
347458
448448
549438
650428
751418
852408
953398
1054388
1155378
1257367
1357367
1458366
1559356
1660355
1760355
1861354
1963343
2063343
2164342
2264342
2364342
2465341
2565341
2666331
2767321
2869310
2970300
3071290

Wind in September

Winds average 21 km/h in September.

Across September, daily wind ranges from about 20 km/h on the calmest days to 23 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202530
Wind speed (km/h)Feels
120light breeze
220light breeze
320breezy
420breezy
520breezy
620breezy
721breezy
821breezy
921breezy
1021breezy
1121breezy
1221breezy
1321breezy
1421breezy
1521breezy
1621breezy
1721breezy
1822breezy
1922breezy
2022breezy
2122breezy
2222breezy
2322breezy
2422breezy
2522breezy
2622breezy
2722breezy
2822breezy
2923breezy
3023breezy

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 5:36 AM to 6:22 AM, and sunset from 6:56 PM to 5:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:366:56
213.35:386:54
313.25:396:52
413.15:416:50
513.15:426:47
613.05:446:45
713.05:466:43
812.95:476:41
912.85:496:38
1012.85:506:36
1112.75:526:34
1212.65:536:31
1312.65:556:29
1412.55:576:27
1512.45:586:24
1612.46:006:22
1712.36:016:20
1812.26:036:17
1912.26:046:15
2012.16:066:13
2112.06:086:11
2212.06:096:08
2311.96:116:06
2411.96:126:04
2511.86:146:01
2611.76:165:59
2711.76:175:57
2811.66:195:54
2911.56:205:52
3011.56:225:50

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.42 kWh/m².

For context, solar energy here swings from a low near 0.75 kWh/m² to a high of 5.82 kWh/m² in June across the year — September's 3.42 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.1Bright
24.0Bright
34.0Bright
44.0Moderate
53.9Moderate
63.9Moderate
73.8Moderate
83.8Moderate
93.7Moderate
103.7Moderate
113.6Moderate
123.6Moderate
133.6Moderate
143.5Moderate
153.5Moderate
163.4Moderate
173.4Moderate
183.3Moderate
193.3Moderate
203.2Moderate
213.2Moderate
223.1Moderate
233.1Moderate
243.0Moderate
253.0Moderate
262.9Moderate
272.9Moderate
282.8Moderate
292.8Moderate
302.7Moderate
Planning a trip in September

Is September a good time to visit Plymouth?

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

5.0
Sightseeing
3rd-best month of the year
0.9
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Plymouth for sightseeing.

What to pack for Plymouth in September

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

In September, Plymouth sees daytime highs around 16°C and nights near 14°C. Worth packing: a warm layer, rain gear and a windbreaker. About 10 days see rain.

a warm layerrain geara windbreaker

Sea temperature near Plymouth in September

The nearest coast averages about 16°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 16 km away) is warmest in August at about 17°C and coldest in March near 9°C.

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

10°15°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan10Bracing
Feb10Bracing
Mar9Bracing
Apr10Bracing
May12Bracing
Jun14Bracing
Jul16Cool
Aug17Cool
Sep16Cool
Oct15Bracing
Nov13Bracing
Dec12Bracing

UV index in Plymouth 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 Plymouth 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
Apr5Moderate
May6High
Jun6High
Jul6High
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Plymouth?

Plymouth sits at 50.4°N, 4.1°W, 14 m above sea level, in United Kingdom. The nearest listed city is Plymstock, 4.0 km away.

Topography around Plymouth

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

Within 3 km, the terrain around Plymouth has only modest variations in elevation — a maximum elevation change of 110 m around an average of 25 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 492 m; within 80 km, large variations in elevation — a maximum elevation change of 651 m.

The land around Plymouth is covered by artificial surfaces (45%) and water (29%) within 3 km, water (36%) and grassland (31%) within 16 km, and water (48%) and grassland (35%) within 80 km.

3 km
110 m
16 km
492 m
80 km
651 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Plymstock 4.0 km · Saltash 7.0 km · Paignton 41 km · Newton Abbot 41 km · Bodmin 43 km · Brixham 45 km · St Austell 45 km · Torquay 45 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 Plymouth (50.3715°, -4.143°, elevation 14 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).