Blaenavon climate — normals and trends
Blaenavon (United Kingdom) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.5 °C and it receives 832 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 (15.9 °C on average) and the coldest is January (3.8 °C). Rainfall peaks in October.
Blaenavon averages 45 frost days, 0 hot days (≥ 30 °C) and 142 rainy days per year.
Blaenavon has warmed by +1.7 °C between 1940 and 2025, or +0.19 °C per decade. This trend is statistically significant.
The number of frost days there went from about 61 to 29 per year over the period.
The hottest day of the period reached 34.5 °C (on 18 July 2022) and the coldest -21.8 °C (on 21 January 1940).
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
BlaenavonWales
- coords
- 51.77°, -3.09°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.5°C
Average daily high
12.7°C
Average daily low
6.2°C
Annual rainfall
832mm
Sunshine / day
7.5h
Mean relative humidity
83%
Average peak wind
20.2km/h
Seasonal range
12.1°C
Frost days (< 0 °C)
45 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
142 d/yr
Annual snowfall
21.9 cm
Average feels-like high
10.0 °C
Average feels-like low
3.3 °C
Average peak gust
42.2 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
+1.7 °C
since 1940
+0.2 °C per decade · r² = 0.44 · 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
34.5 °C
18 July 2022
Coldest day
-21.8 °C
21 January 1940
Wettest day
54 mm
27 December 1979
Windiest day
58.6 km/h
30 November 1954
Strongest gust
129.2 km/h
25 January 1990
Hottest feels-like
34.6 °C
29 July 1948
Coldest feels-like
-27.1 °C
21 January 1940
Snowiest day
26.7 cm
8 January 1982
Sunniest day
16.0 h
22 June 2022
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 | 6.5 °C | +0.3 °C | 105 mm | +29 mm |
| Feb | 7.4 °C | +0.8 °C | 75 mm | +14 mm |
| Mar | 11.8 °C | +2.8 °C | 17 mm | -48 mm |
| Apr | 15.4 °C | +3.6 °C | 59 mm | -2 mm |
| May | 17.9 °C | +2.9 °C | 30 mm | -45 mm |
| Jun | 20.1 °C | +2.2 °C | 61 mm | -1 mm |
| Jul | 22.4 °C | +2.8 °C | 49 mm | -12 mm |
| Aug | 21.7 °C | +2.4 °C | 29 mm | -38 mm |
| Sep | 16.9 °C | 0.0 °C | 98 mm | +31 mm |
| Oct | 13.7 °C | +0.4 °C | 80 mm | -0 mm |
| Nov | 10.9 °C | +1.6 °C | 167 mm | +91 mm |
| Dec | 8.9 °C | +1.8 °C | 149 mm | +69 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 Blaenavon?
Blaenavon has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.5 °C and it receives 832 mm of precipitation per year.
What is the hottest day ever recorded in Blaenavon?
The hottest day measured in Blaenavon between 1940 and 2025 was 18 July 2022, reaching 34.5 °C.
What is the coldest day in Blaenavon?
The coldest day measured in Blaenavon between 1940 and 2025 was 21 January 1940, at -21.8 °C.
Does it snow in Blaenavon?
Yes. Blaenavon gets on average 21.9 cm of snow per year and has around 45 frost days.
Has the climate of Blaenavon warmed?
Yes: Blaenavon warmed by +1.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Blaenavon?
The wettest day measured in Blaenavon between 1940 and 2025 was 27 December 1979, with 54 mm of rain in 24 hours.
What was the windiest day in Blaenavon?
The windiest day measured in Blaenavon between 1940 and 2025 was 30 November 1954, with winds reaching 58.6 km/h.
What is the warmest month in Blaenavon?
The warmest month in Blaenavon is July (15.9 °C on average); the coldest is January (3.8 °C).
How much does it rain in Blaenavon?
Blaenavon receives on average 832 mm of precipitation per year, spread over about 142 rainy days.
Is it sunny in Blaenavon?
Blaenavon gets on average 7.5 hours of sunshine per day, roughly 2,738 hours per year over 1940-2025.
What is the biggest single-day snowfall in Blaenavon?
The heaviest 24-hour snowfall measured in Blaenavon between 1940 and 2025 was 8 January 1982, with 26.7 cm.
Are there tropical nights in Blaenavon?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Blaenavon.
What was the most extreme apparent temperature in Blaenavon?
In Blaenavon, between 1940 and 2025, the highest apparent temperature reached 34.6 °C on 29 July 1948, and the lowest was -27.1 °C on 21 January 1940.
Compare Blaenavon with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Blaenavon