Londonderry County Borough climate — normals and trends
Londonderry County Borough (United Kingdom) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.2 °C and it receives 984 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 (14.3 °C on average) and the coldest is January (4.5 °C). Rainfall peaks in August.
Londonderry County Borough averages 22 frost days, 0 hot days (≥ 30 °C) and 193 rainy days per year.
Londonderry County Borough has warmed by +0.9 °C between 1940 and 2025, or +0.11 °C per decade. This trend is statistically significant.
The number of frost days there went from about 32 to 12 per year over the period.
The hottest day of the period reached 28.2 °C (on 12 July 2025) and the coldest -13.7 °C (on 1 March 1947).
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
Londonderry County BoroughNorthern Ireland
- coords
- 55.00°, -7.31°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.2°C
Average daily high
11.8°C
Average daily low
6.5°C
Annual rainfall
984mm
Sunshine / day
7.2h
Mean relative humidity
83%
Average peak wind
21.8km/h
Seasonal range
9.8°C
Frost days (< 0 °C)
22 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
193 d/yr
Annual snowfall
21.9 cm
Average feels-like high
8.9 °C
Average feels-like low
3.3 °C
Average peak gust
47.4 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
9.2 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+0.9 °C
since 1940
+0.1 °C per decade · r² = 0.25 · 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
28.2 °C
12 July 2025
Coldest day
-13.7 °C
1 March 1947
Wettest day
49 mm
16 August 1970
Windiest day
63.8 km/h
16 September 1961
Strongest gust
140.4 km/h
23 May 2011
Hottest feels-like
32.2 °C
29 July 1948
Coldest feels-like
-18.3 °C
1 March 1947
Snowiest day
28.0 cm
30 March 2010
Sunniest day
17.0 h
9 June 1941
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 | 6.9 °C | +0.3 °C | 49 mm | -34 mm |
| Feb | 8.1 °C | +1.0 °C | 72 mm | +4 mm |
| Mar | 11.0 °C | +2.2 °C | 26 mm | -48 mm |
| Apr | 14.4 °C | +3.4 °C | 92 mm | +20 mm |
| May | 16.3 °C | +2.6 °C | 69 mm | -11 mm |
| Jun | 16.9 °C | +0.9 °C | 114 mm | +33 mm |
| Jul | 18.5 °C | +1.3 °C | 71 mm | -17 mm |
| Aug | 18.9 °C | +1.7 °C | 67 mm | -27 mm |
| Sep | 15.2 °C | -0.2 °C | 106 mm | +21 mm |
| Oct | 12.5 °C | 0.0 °C | 134 mm | +44 mm |
| Nov | 9.9 °C | +0.8 °C | 129 mm | +46 mm |
| Dec | 8.4 °C | +1.1 °C | 80 mm | -8 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 Londonderry County Borough?
Londonderry County Borough has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.2 °C and it receives 984 mm of precipitation per year.
What is the hottest day ever recorded in Londonderry County Borough?
The hottest day measured in Londonderry County Borough between 1940 and 2025 was 12 July 2025, reaching 28.2 °C.
What is the coldest day in Londonderry County Borough?
The coldest day measured in Londonderry County Borough between 1940 and 2025 was 1 March 1947, at -13.7 °C.
Does it snow in Londonderry County Borough?
Yes. Londonderry County Borough gets on average 21.9 cm of snow per year and has around 22 frost days.
Has the climate of Londonderry County Borough warmed?
Yes: Londonderry County Borough warmed by +0.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Londonderry County Borough?
The wettest day measured in Londonderry County Borough between 1940 and 2025 was 16 August 1970, with 49 mm of rain in 24 hours.
What was the windiest day in Londonderry County Borough?
The windiest day measured in Londonderry County Borough between 1940 and 2025 was 16 September 1961, with winds reaching 63.8 km/h.
What is the warmest month in Londonderry County Borough?
The warmest month in Londonderry County Borough is July (14.3 °C on average); the coldest is January (4.5 °C).
How much does it rain in Londonderry County Borough?
Londonderry County Borough receives on average 984 mm of precipitation per year, spread over about 193 rainy days.
Is it sunny in Londonderry County Borough?
Londonderry County Borough gets on average 7.2 hours of sunshine per day, roughly 2,628 hours per year over 1940-2025.
What is the biggest single-day snowfall in Londonderry County Borough?
The heaviest 24-hour snowfall measured in Londonderry County Borough between 1940 and 2025 was 30 March 2010, with 28.0 cm.
Are there tropical nights in Londonderry County Borough?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Londonderry County Borough.
What was the most extreme apparent temperature in Londonderry County Borough?
In Londonderry County Borough, between 1940 and 2025, the highest apparent temperature reached 32.2 °C on 29 July 1948, and the lowest was -18.3 °C on 1 March 1947.
Compare Londonderry County Borough with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Londonderry County Borough