Climate Insights for Oyonnax

The climate in Oyonnax is temperate. The average annual temperature is 12°C and approximately 1425mm of precipitation falls per year. Oyonnax receives a notable amount of rainfall throughout the year, including during its driest month. Oyonnax is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are January, December, February, when temperatures can drop to 1°C. Snowfall occurs from January to December, with around 120cm accumulating over the season.

Temperatures in Oyonnax vary considerably across the year, with a 26°C difference between the coldest and warmest months. The warmest month is July, when average highs reach 27°C and the mean temperature sits around 21°C. January is the coolest month, with minimum temperatures around 1°C and an average of 3°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between September and October, with a 5°C shift in average temperatures.

Oyonnax is a fairly wet location, receiving approximately 1425mm of precipitation annually, which averages out to around 119mm per month. The wettest month is December, averaging 177mm of rainfall. January and May also tend to see above-average precipitation. The driest month is July, with just 56mm. That's 122mm less than December, the wettest month. Precipitation varies noticeably between seasons, with the first half (January to June) of the year generally seeing more rainfall. Snowfall is a regular feature from January to December, with around 120cm accumulating over the season. January typically sees the most snow at around 31cm.

Oyonnax is relatively calm, with an average annual wind speed of 3km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is February, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.

It is currently summer in Oyonnax, which began on June 21, 2026. Oyonnax 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 July at around 27°C, while the coldest stretch bottoms out in January near 1°C. Autumn is next, beginning on September 23, 2026 — 91 days from now.

The best time to visit Oyonnax is during 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 70mm per month. By contrast, January can be quite cold with temperatures dropping to 1°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Oyonnax 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.