Oroville climate — normals and trends
Oroville (United States) has a hot-summer mediterranean climate (Csa) under the Köppen-Geiger classification. Its mean annual temperature is 16.1 °C and it receives 1,085 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 (26.2 °C on average) and the coldest is January (7.5 °C). Rainfall peaks in January.
Oroville averages 12 frost days, 99 hot days (≥ 30 °C) and 74 rainy days per year.
Oroville has warmed by +2.3 °C between 1940 and 2025, or +0.27 °C per decade. This trend is statistically significant.
The number of frost days there went from about 19 to 5 per year over the period.
The hottest day of the period reached 45.6 °C (on 6 September 2022) and the coldest -11.5 °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
OrovilleCalifornia
- coords
- 39.51°, -121.56°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
16.1°C
Average daily high
22.7°C
Average daily low
10.0°C
Annual rainfall
1,085mm
Sunshine / day
10.5h
Mean relative humidity
57%
Average peak wind
13.0km/h
Seasonal range
18.7°C
Frost days (< 0 °C)
12 d/yr
Hot days (≥ 30 °C)
99 d/yr
Rainy days (≥ 1 mm)
74 d/yr
Annual snowfall
27.7 cm
Average feels-like high
21.3 °C
Average feels-like low
7.7 °C
Average peak gust
32.3 km/h
Tropical nights (≥ 20 °C)
13 d/yr
Solar radiation
18.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.3 °C
since 1940
+0.3 °C per decade · r² = 0.65 · 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
45.6 °C
6 September 2022
Coldest day
-11.5 °C
22 December 1990
Wettest day
143 mm
24 October 2021
Windiest day
45.5 km/h
4 January 2008
Strongest gust
120.2 km/h
4 January 2008
Hottest feels-like
46.4 °C
9 August 1978
Coldest feels-like
-16.7 °C
22 December 1990
Snowiest day
24.0 cm
16 February 1990
Sunniest day
14.3 h
5 July 2020
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 | 15.9 °C | +3.1 °C | 56 mm | -146 mm |
| Feb | 15.6 °C | +0.6 °C | 391 mm | +213 mm |
| Mar | 16.6 °C | -0.4 °C | 203 mm | +44 mm |
| Apr | 22.4 °C | +1.7 °C | 42 mm | -38 mm |
| May | 28.7 °C | +3.2 °C | 17 mm | -24 mm |
| Jun | 32.9 °C | +2.3 °C | 0 mm | -11 mm |
| Jul | 33.6 °C | -0.5 °C | 1 mm | -1 mm |
| Aug | 35.1 °C | +2.1 °C | 1 mm | -2 mm |
| Sep | 30.4 °C | +0.2 °C | 18 mm | +4 mm |
| Oct | 23.0 °C | -1.2 °C | 54 mm | -7 mm |
| Nov | 18.4 °C | +1.6 °C | 136 mm | -6 mm |
| Dec | 13.9 °C | +1.1 °C | 319 mm | +124 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 Oroville?
Oroville has a hot-summer mediterranean climate (Köppen Csa). Over 1940-2025, the average annual temperature is 16.1 °C and it receives 1,085 mm of precipitation per year.
What is the hottest day ever recorded in Oroville?
The hottest day measured in Oroville between 1940 and 2025 was 6 September 2022, reaching 45.6 °C.
What is the coldest day in Oroville?
The coldest day measured in Oroville between 1940 and 2025 was 22 December 1990, at -11.5 °C.
Does it snow in Oroville?
Yes. Oroville gets on average 27.7 cm of snow per year and has around 12 frost days.
Has the climate of Oroville warmed?
Yes: Oroville warmed by +2.3 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Oroville?
The wettest day measured in Oroville between 1940 and 2025 was 24 October 2021, with 143 mm of rain in 24 hours.
What was the windiest day in Oroville?
The windiest day measured in Oroville between 1940 and 2025 was 4 January 2008, with winds reaching 45.5 km/h.
What is the warmest month in Oroville?
The warmest month in Oroville is July (26.2 °C on average); the coldest is January (7.5 °C).
How much does it rain in Oroville?
Oroville receives on average 1,085 mm of precipitation per year, spread over about 74 rainy days.
Is it sunny in Oroville?
Oroville gets on average 10.5 hours of sunshine per day, roughly 3,833 hours per year over 1940-2025.
What is the biggest single-day snowfall in Oroville?
The heaviest 24-hour snowfall measured in Oroville between 1940 and 2025 was 16 February 1990, with 24.0 cm.
Are there tropical nights in Oroville?
Yes: Oroville has on average 13 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Oroville?
In Oroville, between 1940 and 2025, the highest apparent temperature reached 46.4 °C on 9 August 1978, and the lowest was -16.7 °C on 22 December 1990.
Compare Oroville with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Oroville