Average temperatures, rainfall and packing tips for Oslo, Norway in September
September in Oslo is typically mild, with average daytime highs around 16°C and nights near 9°C. Temperature-wise it sits mid-range for Oslo (the 5th warmest month).
September is one of the wetter months in Oslo, with around 109 mm of rain - plan around showers.
If your dates are flexible, the most comfortable months in Oslo are usually May, June, July and August.
← Oslo weather tomorrow (live)
In September, Oslo averages a daytime high of about 16°C and a night-time low of around 9°C, based on recent historical data.
September is one of the wetter months in Oslo, with around 109 mm of rain - plan around showers.
September is a workable time to visit Oslo, with mild days - just pack accordingly. If your dates are flexible, the most comfortable months in Oslo are usually May, June, July and August.