Isle of Lewis climate — normals and trends
Isle of Lewis (United Kingdom) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.0 °C and it receives 1,037 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 (13.7 °C on average) and the coldest is January (4.9 °C). Rainfall peaks in October.
Isle of Lewis averages 17 frost days, 0 hot days (≥ 30 °C) and 203 rainy days per year.
Isle of Lewis has warmed by +1.6 °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 25 to 9 per year over the period.
The hottest day of the period reached 26.8 °C (on 3 August 1999) and the coldest -9.1 °C (on 26 February 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
Isle of LewisScotland
- coords
- 58.22°, -6.39°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.0°C
Average daily high
11.3°C
Average daily low
6.6°C
Annual rainfall
1,037mm
Sunshine / day
7.5h
Mean relative humidity
80%
Average peak wind
26.5km/h
Seasonal range
8.8°C
Frost days (< 0 °C)
17 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
203 d/yr
Annual snowfall
18.4 cm
Average feels-like high
7.8 °C
Average feels-like low
2.8 °C
Average peak gust
51.4 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
9.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.53 · 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
26.8 °C
3 August 1999
Coldest day
-9.1 °C
26 February 1947
Wettest day
44 mm
11 August 2014
Windiest day
78.5 km/h
9 January 2015
Strongest gust
170.3 km/h
9 January 2015
Hottest feels-like
29.2 °C
30 July 1948
Coldest feels-like
-14.6 °C
26 February 1947
Snowiest day
15.4 cm
13 December 1950
Sunniest day
17.1 h
16 June 1949
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 | 7.3 °C | +0.6 °C | 50 mm | -42 mm |
| Feb | 8.5 °C | +1.5 °C | 86 mm | +13 mm |
| Mar | 10.8 °C | +2.5 °C | 89 mm | +7 mm |
| Apr | 13.4 °C | +3.1 °C | 52 mm | -21 mm |
| May | 14.4 °C | +1.6 °C | 59 mm | -19 mm |
| Jun | 15.8 °C | +0.9 °C | 126 mm | +46 mm |
| Jul | 18.7 °C | +2.5 °C | 90 mm | +1 mm |
| Aug | 17.6 °C | +1.3 °C | 85 mm | -8 mm |
| Sep | 15.7 °C | +1.3 °C | 98 mm | +1 mm |
| Oct | 12.7 °C | +0.8 °C | 170 mm | +68 mm |
| Nov | 9.7 °C | +0.7 °C | 99 mm | +11 mm |
| Dec | 9.1 °C | +1.7 °C | 93 mm | +3 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 Isle of Lewis?
Isle of Lewis has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.0 °C and it receives 1,037 mm of precipitation per year.
What is the hottest day ever recorded in Isle of Lewis?
The hottest day measured in Isle of Lewis between 1940 and 2025 was 3 August 1999, reaching 26.8 °C.
What is the coldest day in Isle of Lewis?
The coldest day measured in Isle of Lewis between 1940 and 2025 was 26 February 1947, at -9.1 °C.
Does it snow in Isle of Lewis?
Yes. Isle of Lewis gets on average 18.4 cm of snow per year and has around 17 frost days.
Has the climate of Isle of Lewis warmed?
Yes: Isle of Lewis warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Isle of Lewis?
The wettest day measured in Isle of Lewis between 1940 and 2025 was 11 August 2014, with 44 mm of rain in 24 hours.
What was the windiest day in Isle of Lewis?
The windiest day measured in Isle of Lewis between 1940 and 2025 was 9 January 2015, with winds reaching 78.5 km/h.
What is the warmest month in Isle of Lewis?
The warmest month in Isle of Lewis is July (13.7 °C on average); the coldest is January (4.9 °C).
How much does it rain in Isle of Lewis?
Isle of Lewis receives on average 1,037 mm of precipitation per year, spread over about 203 rainy days.
Is it sunny in Isle of Lewis?
Isle of Lewis 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 Isle of Lewis?
The heaviest 24-hour snowfall measured in Isle of Lewis between 1940 and 2025 was 13 December 1950, with 15.4 cm.
Are there tropical nights in Isle of Lewis?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Isle of Lewis.
What was the most extreme apparent temperature in Isle of Lewis?
In Isle of Lewis, between 1940 and 2025, the highest apparent temperature reached 29.2 °C on 30 July 1948, and the lowest was -14.6 °C on 26 February 1947.
Compare Isle of Lewis with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Isle of Lewis