Tualatin climate — normals and trends
Tualatin (United States) has a warm-summer mediterranean climate (Csb) under the Köppen-Geiger classification. Its mean annual temperature is 11.3 °C and it receives 1,256 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 (19.4 °C on average) and the coldest is January (4.1 °C). Rainfall peaks in December.
Tualatin averages 35 frost days, 21 hot days (≥ 30 °C) and 147 rainy days per year.
Tualatin 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 45 to 25 per year over the period.
The hottest day of the period reached 47.4 °C (on 28 June 2021) and the coldest -21.8 °C (on 31 January 1950).
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
TualatinOregon
- coords
- 45.38°, -122.76°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
11.3°C
Average daily high
16.4°C
Average daily low
6.8°C
Annual rainfall
1,256mm
Sunshine / day
8.7h
Mean relative humidity
74%
Average peak wind
12.7km/h
Seasonal range
15.3°C
Frost days (< 0 °C)
35 d/yr
Hot days (≥ 30 °C)
21 d/yr
Rainy days (≥ 1 mm)
147 d/yr
Annual snowfall
25.3 cm
Average feels-like high
15.0 °C
Average feels-like low
4.7 °C
Average peak gust
31.4 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
13.6 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.43 · 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
47.4 °C
28 June 2021
Coldest day
-21.8 °C
31 January 1950
Wettest day
83 mm
24 November 1960
Windiest day
49.7 km/h
14 November 1981
Strongest gust
113.4 km/h
12 October 1962
Hottest feels-like
45.6 °C
28 June 2021
Coldest feels-like
-26.1 °C
31 January 1950
Snowiest day
16.1 cm
20 January 1943
Sunniest day
15.2 h
16 June 2025
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 | 8.6 °C | +1.2 °C | 85 mm | -96 mm |
| Feb | 9.0 °C | -0.7 °C | 149 mm | +6 mm |
| Mar | 13.2 °C | +0.9 °C | 210 mm | +63 mm |
| Apr | 17.8 °C | +2.7 °C | 62 mm | -43 mm |
| May | 20.1 °C | +1.2 °C | 37 mm | -34 mm |
| Jun | 24.5 °C | +2.3 °C | 24 mm | -20 mm |
| Jul | 28.5 °C | +2.0 °C | 1 mm | -12 mm |
| Aug | 28.7 °C | +2.2 °C | 15 mm | -5 mm |
| Sep | 24.9 °C | +1.5 °C | 33 mm | -15 mm |
| Oct | 16.3 °C | -0.5 °C | 107 mm | -3 mm |
| Nov | 12.1 °C | +1.5 °C | 151 mm | -31 mm |
| Dec | 10.7 °C | +3.2 °C | 249 mm | +57 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 Tualatin?
Tualatin has a warm-summer mediterranean climate (Köppen Csb). Over 1940-2025, the average annual temperature is 11.3 °C and it receives 1,256 mm of precipitation per year.
What is the hottest day ever recorded in Tualatin?
The hottest day measured in Tualatin between 1940 and 2025 was 28 June 2021, reaching 47.4 °C.
What is the coldest day in Tualatin?
The coldest day measured in Tualatin between 1940 and 2025 was 31 January 1950, at -21.8 °C.
Does it snow in Tualatin?
Yes. Tualatin gets on average 25.3 cm of snow per year and has around 35 frost days.
Has the climate of Tualatin warmed?
Yes: Tualatin warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Tualatin?
The wettest day measured in Tualatin between 1940 and 2025 was 24 November 1960, with 83 mm of rain in 24 hours.
What was the windiest day in Tualatin?
The windiest day measured in Tualatin between 1940 and 2025 was 14 November 1981, with winds reaching 49.7 km/h.
What is the warmest month in Tualatin?
The warmest month in Tualatin is July (19.4 °C on average); the coldest is January (4.1 °C).
How much does it rain in Tualatin?
Tualatin receives on average 1,256 mm of precipitation per year, spread over about 147 rainy days.
Is it sunny in Tualatin?
Tualatin gets on average 8.7 hours of sunshine per day, roughly 3,175 hours per year over 1940-2025.
What is the biggest single-day snowfall in Tualatin?
The heaviest 24-hour snowfall measured in Tualatin between 1940 and 2025 was 20 January 1943, with 16.1 cm.
Are there tropical nights in Tualatin?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Tualatin.
What was the most extreme apparent temperature in Tualatin?
In Tualatin, between 1940 and 2025, the highest apparent temperature reached 45.6 °C on 28 June 2021, and the lowest was -26.1 °C on 31 January 1950.
Compare Tualatin with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Tualatin