With a population of around 17,300, Onex sits in Geneva, Switzerland. The city operates in the Europe/Zurich time zone.
In 2025, Onex recorded an average annual temperature of 52°F. The hottest temperatures reached 98°F in August; the coolest were 22°F in November. Total precipitation for the year was 41 inches, with the wettest month being January. Snowfall for the year totaled approximately 3 inches.
View current conditions and forecast for Onex · More cities in Geneva