Climate Insights for John Day

The climate in John Day is cool. The average annual temperature is 8°C and approximately 679mm of precipitation falls per year. March is the wettest month, receiving around 86mm of rainfall. John Day 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 December, January, February, when temperatures can drop to -6°C. John Day experiences heavy snowfall, typically from January through December.

Temperatures in John Day vary considerably across the year, with a 35°C difference between the coldest and warmest months. The warmest month is August, when average highs reach 29°C and the mean temperature sits around 20°C. The coldest month is December, when overnight lows fall to -6°C and the daily average is -3°C. On average, daily temperatures fluctuate by about 13°C between overnight lows and afternoon highs. The sharpest temperature change occurs between September and October, with a 7°C shift in average temperatures.

John Day is a relatively dry area, receiving approximately 679mm of precipitation annually, which averages out to around 57mm per month. The wettest month is March, averaging 86mm of rainfall. February and January also tend to see above-average precipitation. The driest month is July, with just 6mm. That's 80mm less than March, 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. John Day receives heavy snowfall, accumulating around 251cm annually from January through December. The snowiest month is February, with approximately 59cm. Winter travel should account for significant snow cover.

John Day is relatively calm, with an average annual wind speed of 2km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 2km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 0km/h between the calmest and windiest months.

It is currently summer in John Day, which began on June 21, 2026. John Day 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 29°C, while the coldest stretch bottoms out in December near -6°C. Autumn is next, beginning on September 23, 2026 — 94 days from now.

The best time to visit John Day is during July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 20°C with modest rainfall averaging 9mm per month. By contrast, December can be quite cold with temperatures dropping to -6°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for John Day 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.