Oslo Weather Overview:
Oslo’s weather is unusual for a city that’s so far north. Tempered by the Gulf Stream, the city enjoys milder winters than would be expected and summers can be warm and regularly suffers heatwaves. This is the land of the midnight sun and in midsummer you can expect 18 hours of daylights per day with often 16 hours of sunshine.
All Time Highs and Lows:
The highest temperature ever recorded in Oslo was 35C which was experienced on 21st July 1901. The lowest temperature ever seen was -27.1C which was reached in January 1942.
The city enjoys a Hemiboreal Humid Continental climate according to the Koppen classification but one which is influenced by the Gulf Stream that washes the coast near the city.
Spring: Snowy days are much less frequent in early spring with three expected in March, one likely in April and none in May. The temperature rises from 5C in early spring to 15C in the middle of May whilst rainfall is slowly increasing to its summer peak. Already, before summer has begun, seven hours of sun per day can be expected in May.
Summer: Summer is a great time to visit Oslo, not only do you have seemingly endless hours of daylight, the temperatures are warm and pleasant, making perfect conditions for enjoying the outdoor life in the city. Rainfall can be a problem and is at its highest for the year over the summer months at twice the January average.
Autumn: The temperatures and sunshine tail off dramatically after mid-September with daylight hours a fifth of July’s by the time you get to the end of November. Temperatures will have plummeted from 20C at the beginning of September to barely above freezing at the end of November.
Winter: It’s usually from the beginning of January that appreciable amounts of snow accumulate. The temperature over this period rarely climbs above zero and you’ll be lucky to see an hour of sunlight a day as the city heads towards the shortest day. In cold winters the waters of the fjord can also freeze over.
Best Time to Visit:
The summer is by far the best time to see Oslo, not just because of the great weather but also because of the unending daylight. The city is warm enough for shorts and a T-shirt without you getting too hot enjoying the sights on foot.