Colwyn Bay climate — normals and trends
Colwyn Bay (United Kingdom) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.5 °C and it receives 917 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (15.2 °C on average) and the coldest is January (4.3 °C). Rainfall peaks in December.
Colwyn Bay averages 32 frost days, 0 hot days (≥ 30 °C) and 173 rainy days per year.
Colwyn Bay has warmed by +1.5 °C between 1940 and 2025, or +0.18 °C per decade. This trend is statistically significant.
The number of frost days there went from about 48 to 16 per year over the period.
The hottest day of the period reached 33.6 °C (on 18 July 2022) and the coldest -17.2 °C (on 12 January 1963).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
Colwyn BayWales
- coords
- 53.29°, -3.73°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.5°C
Average daily high
12.3°C
Average daily low
6.6°C
Annual rainfall
917mm
Sunshine / day
7.9h
Mean relative humidity
82%
Average peak wind
20.8km/h
Seasonal range
10.9°C
Frost days (< 0 °C)
32 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
173 d/yr
Annual snowfall
20.8 cm
Average feels-like high
9.5 °C
Average feels-like low
3.6 °C
Average peak gust
46.2 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
10.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.5 °C
since 1940
+0.2 °C per decade · r² = 0.40 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
33.6 °C
18 July 2022
Coldest day
-17.2 °C
12 January 1963
Wettest day
54 mm
24 September 2012
Windiest day
66.7 km/h
24 December 1997
Strongest gust
144.4 km/h
23 April 1947
Hottest feels-like
33.7 °C
29 July 1948
Coldest feels-like
-21.3 °C
12 January 1963
Snowiest day
16.4 cm
16 January 1955
Sunniest day
16.4 h
26 June 1995
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 6.4 °C | 0.0 °C | 121 mm | +42 mm |
| Feb | 7.6 °C | +0.9 °C | 40 mm | -25 mm |
| Mar | 11.3 °C | +2.6 °C | 21 mm | -48 mm |
| Apr | 15.0 °C | +3.8 °C | 66 mm | -2 mm |
| May | 16.7 °C | +2.3 °C | 37 mm | -37 mm |
| Jun | 18.7 °C | +1.7 °C | 86 mm | +12 mm |
| Jul | 19.9 °C | +1.4 °C | 58 mm | -18 mm |
| Aug | 20.5 °C | +2.2 °C | 34 mm | -47 mm |
| Sep | 16.3 °C | +0.1 °C | 129 mm | +52 mm |
| Oct | 13.2 °C | +0.2 °C | 79 mm | -3 mm |
| Nov | 10.8 °C | +1.5 °C | 151 mm | +66 mm |
| Dec | 8.9 °C | +1.6 °C | 105 mm | +18 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Colwyn Bay?
Colwyn Bay has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.5 °C and it receives 917 mm of precipitation per year.
What is the hottest day ever recorded in Colwyn Bay?
The hottest day measured in Colwyn Bay between 1940 and 2025 was 18 July 2022, reaching 33.6 °C.
What is the coldest day in Colwyn Bay?
The coldest day measured in Colwyn Bay between 1940 and 2025 was 12 January 1963, at -17.2 °C.
Does it snow in Colwyn Bay?
Yes. Colwyn Bay gets on average 20.8 cm of snow per year and has around 32 frost days.
Has the climate of Colwyn Bay warmed?
Yes: Colwyn Bay warmed by +1.5 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Colwyn Bay?
The wettest day measured in Colwyn Bay between 1940 and 2025 was 24 September 2012, with 54 mm of rain in 24 hours.
What was the windiest day in Colwyn Bay?
The windiest day measured in Colwyn Bay between 1940 and 2025 was 24 December 1997, with winds reaching 66.7 km/h.
What is the warmest month in Colwyn Bay?
The warmest month in Colwyn Bay is July (15.2 °C on average); the coldest is January (4.3 °C).
How much does it rain in Colwyn Bay?
Colwyn Bay receives on average 917 mm of precipitation per year, spread over about 173 rainy days.
Is it sunny in Colwyn Bay?
Colwyn Bay gets on average 7.9 hours of sunshine per day, roughly 2,884 hours per year over 1940-2025.
What is the biggest single-day snowfall in Colwyn Bay?
The heaviest 24-hour snowfall measured in Colwyn Bay between 1940 and 2025 was 16 January 1955, with 16.4 cm.
Are there tropical nights in Colwyn Bay?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Colwyn Bay.
What was the most extreme apparent temperature in Colwyn Bay?
In Colwyn Bay, between 1940 and 2025, the highest apparent temperature reached 33.7 °C on 29 July 1948, and the lowest was -21.3 °C on 12 January 1963.
Compare Colwyn Bay with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Colwyn Bay