Oslo Weather in September
Norway · Humid Continental climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
September in Oslo sees average temperatures ranging from a low of 10.1°C (50.2°F) to a high of 17.0°C (62.6°F), with a mean of 13.4°C (56.1°F). Compared to the annual average of 7.6°C (45.7°F), this month is 5.8°C warmer than the yearly norm. Precipitation averages 85.5mm, making it approximately 6.0mm wetter than the monthly average of 80.0mm. The city receives an average of 7.7 hours of sunshine per day during September, with relative humidity averaging 79.3%. Wind speeds reach an average maximum of 15.8 km/h. For travelers, this month offers a temperature experience in Oslo, with wetter-than-average conditions compared to the rest of the year.
There's something about Oslo in winter that feels like the city is performing for itself. I arrived in February expecting gloom and found magic: 50cm of snow, 4 hours of daylight, and the Holmenkollen ski jump lit up against the dark sky. Norwegians don't hibernate — they ski to work, light candles everywhere, and embrace kos, their version of coziness. Summer (June-August) is its opposite: 22°C, 18 hours of light, the fjord dotted with boats. May 17 (Constitution Day) is when the city bursts into bunader and parades. Each season here is a deliberate cultural choice.
September vs Adjacent Months
| Metric | August | September | October |
|---|---|---|---|
| Mean Temp | 16.8°C (62.2°F) | 13.4°C (56.1°F) | 8.1°C (46.6°F) |
| Rainfall | 91.1mm | 85.5mm | 96.4mm |
| Sunshine | 10.6 hrs | 7.7 hrs | 4.8 hrs |
| Humidity | 75.5% | 79.3% | 85.5% |
| Wind | 15.7 km/h | 15.8 km/h | 16.8 km/h |
| Rainy Days | 16.4 | 14.8 | 16.4 |
| Snowfall | 0.0 cm | 0.0 cm | 3.8 cm |
Seasonal Context
September falls in Autumn in the Northern Hemisphere. Autumn sees temperatures gradually cooling from summer highs. For travelers visiting Oslo in September, the data indicates mixed conditions based on the combination of temperature, precipitation, and daylight hours.
Frequently Asked Questions
What is the average temperature in Oslo in September?
The average temperature in Oslo during September ranges from 10.1°C (50.2°F) to 17.0°C (62.6°F), with a mean of 13.4°C (56.1°F).
How much does it rain in Oslo in September?
Oslo receives an average of 85.5mm of precipitation in September, spread across approximately 14.8 rainy days.
What should I pack for Oslo in September?
Based on September weather data, pack warm layers, a medium jacket, and waterproof outerwear.
Is September a good time to visit Oslo?
September is a cooler month, suitable for travelers who prefer mild weather and fewer crowds. Pack warm layers and enjoy indoor attractions.
Other Months for Oslo
Cities with Similar September Climate (Humid Continental)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 59.91°, 10.75°. Timezone: Europe/Oslo. Last updated: 2026-07-30.