Caernarfon weather by month

Check out Caernarfon weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature
Rainfall
Sunshine & UV index

Temperature in Caernarfon (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	7	7	8	11	14	17	18	18	16	14	10	8
Min temperature (night-time)	2	2	3	4	7	9	11	11	10	8	4	3
Heat & Humidity	0	0	0	0	0	0	0	0	0	0	0	0
Sea temperature	8	7	7	8	10	13	15	16	15	14	12	10

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & UV index in Caernarfon

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	1	3	3	5	6	6	6	5	4	3	2	1
Daily hours of daylight	8	10	12	14	16	17	16	15	13	11	9	8
UV Index (Maximum)	0	1	2	4	5	6	6	5	4	2	1	0

Rainfall in Caernarfon

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	20	16	18	14	15	14	14	15	16	19	20	20
Average monthly rainfall (mm)	164	111	128	92	90	94	99	131	141	174	183	183

More about Caernarfon

Caernarfon by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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The climate guide for Wales (Caernarfon) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Caernarfon?

Caernarfon has a temperate climate with warm summers and some rainfall in all months.

Caernarfon weather in January

Expect daytime maximum temperatures of 7°C in Caernarfon, Wales in January based on long-term weather averages. There is 1 hour of sunshine per day on average with 20 days with some rainfall and typically 164 mm of rainfall in the month.

7
7°C max day temperature
1
1 hour of sunshine per day
20
20 days with some rainfall
2
2°C min night temperature
8
8 hours of daylight per day
0
No heat & humidity
164
164 mm of monthly rainfall
0
No UV (Maximum) Index UV index
8
8°C sea temperature

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Caernarfon weather in February

Expect daytime maximum temperatures of 7°C in Caernarfon, Wales in February based on long-term weather averages. There are 3 hours of sunshine per day on average with 16 days with some rainfall and typically 111 mm of rainfall in the month.

7
7°C max day temperature
3
3 hours of sunshine per day
16
16 days with some rainfall
2
2°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
111
111 mm of monthly rainfall
1
1 (Low) UV index
7
7°C sea temperature

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Caernarfon weather in March

Expect daytime maximum temperatures of 8°C in Caernarfon, Wales in March based on long-term weather averages. There are 3 hours of sunshine per day on average with 18 days with some rainfall and typically 128 mm of rainfall in the month.

8
8°C max day temperature
3
3 hours of sunshine per day
18
18 days with some rainfall
3
3°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
128
128 mm of monthly rainfall
2
2 (Low) UV index
7
7°C sea temperature

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Caernarfon weather in April

Expect daytime maximum temperatures of 11°C in Caernarfon, Wales in April based on long-term weather averages. There are 5 hours of sunshine per day on average with 14 days with some rainfall and typically 92 mm of rainfall in the month.

11
11°C max day temperature
5
5 hours of sunshine per day
14
14 days with some rainfall
4
4°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
92
92 mm of monthly rainfall
4
4 (Moderate) UV index
8
8°C sea temperature

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Caernarfon weather in May

Expect daytime maximum temperatures of 14°C in Caernarfon, Wales in May based on long-term weather averages. There are 6 hours of sunshine per day on average with 15 days with some rainfall and typically 90 mm of rainfall in the month.

14
14°C max day temperature
6
6 hours of sunshine per day
15
15 days with some rainfall
7
7°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
90
90 mm of monthly rainfall
5
5 (Moderate) UV index
10
10°C sea temperature

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Caernarfon weather in June

Expect daytime maximum temperatures of 17°C in Caernarfon, Wales in June based on long-term weather averages. There are 6 hours of sunshine per day on average with 14 days with some rainfall and typically 94 mm of rainfall in the month.

17
17°C max day temperature
6
6 hours of sunshine per day
14
14 days with some rainfall
9
9°C min night temperature
17
17 hours of daylight per day
0
No heat & humidity
94
94 mm of monthly rainfall
6
6 (High) UV index
13
13°C sea temperature

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Caernarfon weather in July

Expect daytime maximum temperatures of 18°C in Caernarfon, Wales in July based on long-term weather averages. There are 6 hours of sunshine per day on average with 14 days with some rainfall and typically 99 mm of rainfall in the month.

18
18°C max day temperature
6
6 hours of sunshine per day
14
14 days with some rainfall
11
11°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
99
99 mm of monthly rainfall
6
6 (High) UV index
15
15°C sea temperature

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Caernarfon weather in August

Expect daytime maximum temperatures of 18°C in Caernarfon, Wales in August based on long-term weather averages. There are 5 hours of sunshine per day on average with 15 days with some rainfall and typically 131 mm of rainfall in the month.

18
18°C max day temperature
5
5 hours of sunshine per day
15
15 days with some rainfall
11
11°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
131
131 mm of monthly rainfall
5
5 (Moderate) UV index
16
16°C sea temperature

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Caernarfon weather in September

Expect daytime maximum temperatures of 16°C in Caernarfon, Wales in September based on long-term weather averages. There are 4 hours of sunshine per day on average with 16 days with some rainfall and typically 141 mm of rainfall in the month.

16
16°C max day temperature
4
4 hours of sunshine per day
16
16 days with some rainfall
10
10°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
141
141 mm of monthly rainfall
4
4 (Moderate) UV index
15
15°C sea temperature

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Caernarfon weather in October

Expect daytime maximum temperatures of 14°C in Caernarfon, Wales in October based on long-term weather averages. There are 3 hours of sunshine per day on average with 19 days with some rainfall and typically 174 mm of rainfall in the month.

14
14°C max day temperature
3
3 hours of sunshine per day
19
19 days with some rainfall
8
8°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
174
174 mm of monthly rainfall
2
2 (Low) UV index
14
14°C sea temperature

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Caernarfon weather in November

Expect daytime maximum temperatures of 10°C in Caernarfon, Wales in November based on long-term weather averages. There are 2 hours of sunshine per day on average with 20 days with some rainfall and typically 183 mm of rainfall in the month.

10
10°C max day temperature
2
2 hours of sunshine per day
20
20 days with some rainfall
4
4°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
183
183 mm of monthly rainfall
1
1 (Low) UV index
12
12°C sea temperature

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Caernarfon weather in December

Expect daytime maximum temperatures of 8°C in Caernarfon, Wales in December based on long-term weather averages. There is 1 hour of sunshine per day on average with 20 days with some rainfall and typically 183 mm of rainfall in the month.