Oakley climate — normals and trends
Oakley (United States) has a warm-summer mediterranean climate (Csb) under the Köppen-Geiger classification. Its mean annual temperature is 15.4 °C and it receives 443 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 (21.0 °C on average) and the coldest is January (8.7 °C). Rainfall peaks in January.
Oakley averages 3 frost days, 47 hot days (≥ 30 °C) and 51 rainy days per year.
Oakley has warmed by +1.4 °C between 1940 and 2025, or +0.17 °C per decade. This trend is statistically significant.
The number of frost days there went from about 5 to 1 per year over the period.
The hottest day of the period reached 42.5 °C (on 2 June 1960) and the coldest -5.3 °C (on 22 December 1990).
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
OakleyCalifornia
- coords
- 38.00°, -121.71°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
15.4°C
Average daily high
21.8°C
Average daily low
10.3°C
Annual rainfall
443mm
Sunshine / day
10.6h
Mean relative humidity
68%
Average peak wind
15.0km/h
Seasonal range
12.3°C
Frost days (< 0 °C)
3 d/yr
Hot days (≥ 30 °C)
47 d/yr
Rainy days (≥ 1 mm)
51 d/yr
Annual snowfall
0.1 cm
Average feels-like high
20.8 °C
Average feels-like low
8.5 °C
Average peak gust
33.2 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
18.9 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.4 °C
since 1940
+0.2 °C per decade · r² = 0.45 · 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
42.5 °C
2 June 1960
Coldest day
-5.3 °C
22 December 1990
Wettest day
94 mm
13 October 2009
Windiest day
43.5 km/h
3 December 1983
Strongest gust
100.8 km/h
12 December 1995
Hottest feels-like
44.8 °C
14 July 1972
Coldest feels-like
-9.5 °C
22 December 1990
Snowiest day
1.5 cm
13 March 1975
Sunniest day
14.2 h
27 June 1958
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 | 15.4 °C | +2.1 °C | 15 mm | -73 mm |
| Feb | 16.8 °C | +1.0 °C | 126 mm | +48 mm |
| Mar | 18.0 °C | +0.1 °C | 59 mm | -8 mm |
| Apr | 21.9 °C | +1.0 °C | 8 mm | -24 mm |
| May | 26.1 °C | +1.8 °C | 1 mm | -13 mm |
| Jun | 26.3 °C | -1.2 °C | 0 mm | -3 mm |
| Jul | 26.6 °C | -2.7 °C | 0 mm | -1 mm |
| Aug | 29.3 °C | +0.3 °C | 0 mm | -1 mm |
| Sep | 28.0 °C | -0.1 °C | 2 mm | -2 mm |
| Oct | 22.9 °C | -1.1 °C | 43 mm | +20 mm |
| Nov | 17.3 °C | -0.4 °C | 83 mm | +29 mm |
| Dec | 12.5 °C | -0.9 °C | 45 mm | -34 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 Oakley?
Oakley has a warm-summer mediterranean climate (Köppen Csb). Over 1940-2025, the average annual temperature is 15.4 °C and it receives 443 mm of precipitation per year.
What is the hottest day ever recorded in Oakley?
The hottest day measured in Oakley between 1940 and 2025 was 2 June 1960, reaching 42.5 °C.
What is the coldest day in Oakley?
The coldest day measured in Oakley between 1940 and 2025 was 22 December 1990, at -5.3 °C.
Does it snow in Oakley?
Almost never: Oakley sees virtually no snow, with about 3 frost days per year.
Has the climate of Oakley warmed?
Yes: Oakley warmed by +1.4 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Oakley?
The wettest day measured in Oakley between 1940 and 2025 was 13 October 2009, with 94 mm of rain in 24 hours.
What was the windiest day in Oakley?
The windiest day measured in Oakley between 1940 and 2025 was 3 December 1983, with winds reaching 43.5 km/h.
What is the warmest month in Oakley?
The warmest month in Oakley is July (21.0 °C on average); the coldest is January (8.7 °C).
How much does it rain in Oakley?
Oakley receives on average 443 mm of precipitation per year, spread over about 51 rainy days.
Is it sunny in Oakley?
Oakley gets on average 10.6 hours of sunshine per day, roughly 3,869 hours per year over 1940-2025.
What is the biggest single-day snowfall in Oakley?
The heaviest 24-hour snowfall measured in Oakley between 1940 and 2025 was 13 March 1975, with 1.5 cm.
Are there tropical nights in Oakley?
Yes: Oakley has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Oakley?
In Oakley, between 1940 and 2025, the highest apparent temperature reached 44.8 °C on 14 July 1972, and the lowest was -9.5 °C on 22 December 1990.
Compare Oakley with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Oakley