Climate Insights for The Dalles

The climate in The Dalles is temperate. The average annual temperature is 11°C and approximately 783mm of precipitation falls per year. December is the wettest month, receiving around 139mm of rainfall. The Dalles is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are January, February, December, when temperatures can drop to -1°C. Snowfall occurs from January to December, with around 138cm accumulating over the season.

Temperatures in The Dalles vary considerably across the year, with a 32°C difference between the coldest and warmest months. The warmest month is August, when average highs reach 31°C and the mean temperature sits around 22°C. The coldest month is January, when overnight lows fall to -1°C and the daily average is 1°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between September and October, with a 7°C shift in average temperatures.

The Dalles is a relatively dry area, receiving approximately 783mm of precipitation annually, which averages out to around 65mm per month. The wettest month is December, averaging 139mm of rainfall. January and November also tend to see above-average precipitation. The driest month is July, with just 4mm. That's 135mm less than December, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Snowfall is a regular feature from January to December, with around 138cm accumulating over the season. February typically sees the most snow at around 41cm.

The Dalles is relatively calm, with an average annual wind speed of 8km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is July, averaging 10km/h, though still comfortable for most outdoor activities. The calmest conditions occur in January, with average winds dropping to 6km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 4km/h gap between the calmest and windiest months. Wind tends to pick up during the summer months. The seasonal averages are 7km/h in winter, 8km/h in spring, 10km/h in summer, 7km/h in autumn.

It is currently summer in The Dalles, which began on June 21, 2026. The Dalles is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 31°C, while the coldest stretch bottoms out in January near -1°C. Autumn is next, beginning on September 23, 2026 (7 days from now).

The best time to visit The Dalles is during June, July, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 20°C with modest rainfall averaging 15mm per month. By contrast, January can be quite cold with temperatures dropping to -1°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for The Dalles based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.