Climate in Oslo (Norway)

The climate of Oslo is Baltic semi-continental, that is, similar to that of the cities located along the coasts of the Baltic Sea, so it is very cold in winter, with average temperatures below freezing (0 °C or 32 °F), and mild or pleasantly warm in summer.
The city is the capital of Norway and is located in the south of the country, on the coast, but inside a fjord more than 80 kilometers (50 miles) deep, where the influence of the sea is less evident than on the coast of the Skagerrak.
At the Blindern university campus, the average temperature of the coldest month (January) is of -2.3 °C (27.9 °F), that of the warmest month (July) is of 18 °C (64.4 °F). Here are the average temperatures.

Precipitation amounts to 830 millimeters (32.7 inches) per year, and is well distributed over the seasons; however, the rainiest seasons are summer and autumn. Here is the average precipitation.

In winter, the temperature stays around freezing or below from November to March. There are about 80 days with snowfall, which occur from late October to mid-April.
However, there are different situations. When Atlantic currents prevail, the temperature can exceed freezing and rain can fall instead of snow: these periods are becoming more and more frequent.
On the other hand, on colder periods, when the currents blow from Siberia or a polar anticyclone moves over Scandinavia, the temperature can drop to -20 °C (-4 °F) or below.
The cold record, -26 °C, was recorded in January 1941. In the years 2010s, the temperature dropped below -20 °C (-4 °F) only in January 2010, with -20.5 °C (-5 °F).
However, in the countryside north of Oslo, it gets even colder. At Gardermoen Airport, located 35 km (21 mi) north of the city, the average minimum in January and February is -7.5 °C (18.5 °F), and the temperature dropped to -35.5 °C (-32 °F) in February 1966.
Owing to the high latitude, in Oslo, the days are short especially in December and early January (the sun sets at 3:10 p.m. in mid-December and at 3:45 p.m. in mid-January), while in February, the days are already a bit longer (in mid-February, the sun sets at 5 p.m.), although the temperature is usually the same as in January.

In spring, in April and May, the temperature rises quickly enough. In early April, it can still snow and the temperature can drop below freezing, while during the month, the first mild days occur. Spring is the season in which Atlantic disturbances are, albeit slightly, less frequent. In the second half of May, during some years, an anticyclone can move over northern Europe and Norway, able to bring a period of nice and warm weather.

Summer, from June to August, is mild or pleasantly warm, with cool nights. The rains can occur also in summer because the flow of Atlantic fronts at these latitudes never stops: in fact, there are 10/11 days with rainfall even in the summer months.
Hot days are rare, though the temperature can sometimes reach as high as 30 °C (86 °F). These hot periods are becoming more frequent due to global warming. In July 2018, the temperature even reached 34.5 °C (94 °F), and the average high was 28.5 °C (83.3 °F).
The days are very long: from May 12 to July 31, you can experience the phenomenon of the white nights, when it does not get completely dark even at midnight. However, the sun sets at 10.45 p.m. in late June, at 10 p.m. in late July, and at 8.45 p.m. in late August.

Autumn, is cool, cloudy and rainy already in September, and then gradually becomes colder. The first snowfalls can be seen already in October. In November, the days are short, it is cold, and the sun is a rarity: in fact, it's already winter.



Altogether, the amount of sunshine in Oslo is acceptable from May to August, thanks also to the length of the days. On the contrary, the sun is practically never seen from November to January, also because of the short days.
On average there are 1,740 hours of sunshine per year. Here are the average sunshine hours per day.

The sea in the Oslo fjord is cold even in summer, however, it reaches 17/17.5 °C (63/63.5 °F) in July and August, which means that the more daring can try to imitate the Norwegians and have a swim. Here are the average sea temperatures.

Best Time

The best time to visit Oslo is the summer, from June to August. The temperature is generally pleasant for outdoor activities, but at night, it can get cool, or even a little cold; moreover, there is a moderate amount of rainy days. However, if you are lucky, you can find daytime temperatures above 25 °C (77 °F). June is slightly cooler than August, but the days are very long, and the phenomenon of the white nights is more evident, especially around the summer solstice, June 21.

Oslo - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a very cold month. The average temperature is of -2.3 °C (28 °F), with a minimum of -4.7 °C (23.6 °F) and a maximum of 0.1 °C (32.1 °F).
On the coldest nights of the month, the temperature usually drops to around -14 °C (7 °F). However, it dropped to -20.5 °C (-4.9 °F) in January 2010.
On the warmest days of the month, the temperature usually reaches around 6.5 °C (43.5 °F). However, it reached 10.4 °C (50.7 °F) in January 2019.
Precipitation amounts to 60 mm (2.4 in), distributed over 10 days.
The day lasts on average 6 hours and 55 minutes. So the days are short.
There are on average 1.5 hours of sunshine per day. So, the sun shines 22% of the time.
The average humidity is 87%. Hence, the air is normally humid.
The average wind speed is 5 kph (3 mph).
The average sea temperature is of 4.5 °C (40.5 °F). Therefore, the sea is very cold for swimming.

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February is generally a very cold month. The average temperature is of -1.8 °C (29 °F), with a minimum of -4.7 °C (23.6 °F) and a maximum of 1.1 °C (33.9 °F).
On the coldest nights of the month, the temperature usually drops to around -13.5 °C (8 °F). However, it dropped to -20.7 °C (-5.3 °F) in February 2001.
On the warmest days of the month, the temperature usually reaches around 7.5 °C (46 °F). However, it reached 13.7 °C (56.7 °F) in February 1998.
Precipitation amounts to 45 mm (1.8 in), distributed over 8 days.
The day lasts on average 9 hours and 10 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 31% of the time.
The average humidity is 84%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 3.5 °C (38.5 °F). Therefore, the sea is very cold for swimming.

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March is generally a cold month. The average temperature is of 1.6 °C (35 °F), with a minimum of -2.1 °C (28.3 °F) and a maximum of 5.3 °C (41.6 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -9.5 °C (15.5 °F). However, it dropped to -16.9 °C (1.6 °F) in March 2005.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 13 °C (55.5 °F). However, it reached 21.5 °C (70.7 °F) in March 2012.
Precipitation amounts to 40 mm (1.6 in), distributed over 7 days.
The day lasts on average 11 hours and 55 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 3.5 °C (38.5 °F). Therefore, the sea is very cold for swimming.

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April is generally a quite cold month. The average temperature is of 6.5 °C (44 °F), with a minimum of 2.1 °C (35.8 °F) and a maximum of 11 °C (51.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -3.5 °C (25.5 °F). However, it dropped to -7.3 °C (18.9 °F) in April 1996.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 18.5 °C (65.5 °F). However, it reached 25.4 °C (77.7 °F) in April 2000.
Precipitation amounts to 50 mm (2 in), distributed over 8 days.
The day lasts on average 14 hours and 40 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 41% of the time.
The average humidity is 66%.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 6 °C (43 °F). Therefore, the sea is very cold for swimming.

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May is generally a mild month. The average temperature is of 11.7 °C (53 °F), with a minimum of 6.8 °C (44.2 °F) and a maximum of 16.7 °C (62 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 0.5 °C (33 °F). However, it dropped to -1.8 °C (28.8 °F) in May 2019.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 24.5 °C (76.5 °F). However, it reached 31.1 °C (88 °F) in May 2018.
Precipitation amounts to 60 mm (2.4 in), distributed over 9 days.
The day lasts on average 17 hours and 10 minutes. So the days are very long.
There are on average 8 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 63%.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 10.5 °C (50.5 °F). Therefore, the sea is very cold for swimming.

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June is generally a very mild month. The average temperature is of 15.6 °C (60 °F), with a minimum of 10.8 °C (51.5 °F) and a maximum of 20.4 °C (68.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 6 °C (42.5 °F). However, it dropped to 3 °C (37.4 °F) in June 2005.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 27 °C (80.5 °F). However, it reached 31.9 °C (89.4 °F) in June 2018.
Precipitation amounts to 80 mm (3.1 in), distributed over 10 days.
The day lasts on average 18 hours and 40 minutes. So the days are very long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 8 hours of sunshine per day. So, the sun shines 42% of the time.
The average humidity is 65%.
The average wind speed is 7 kph (4 mph).
The average sea temperature is of 14.5 °C (58 °F). Therefore, the sea is very cold for swimming.

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July, the warmest month of the year, is generally a very mild month. The average temperature is of 18.0 °C (64 °F), with a minimum of 13.4 °C (56.1 °F) and a maximum of 22.7 °C (72.9 °F).
On the coldest nights of the month, the temperature usually drops to around 9 °C (48 °F). However, it dropped to 6.5 °C (43.7 °F) in July 1995.
On the warmest days of the month, the temperature usually reaches around 28.5 °C (83.5 °F). However, it reached 34.6 °C (94.3 °F) in July 2018.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 days.
The day lasts on average 17 hours and 55 minutes. So the days are very long.
There are on average 8 hours of sunshine per day. So, the sun shines 44% of the time.
The average humidity is 69%.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 17 °C (63 °F). Therefore, the sea is cold for swimming.

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August is generally a very mild month. The average temperature is of 16.9 °C (62 °F), with a minimum of 12.5 °C (54.6 °F) and a maximum of 21.3 °C (70.4 °F).
On the coldest nights of the month, the temperature usually drops to around 7 °C (45 °F). However, it dropped to 4.2 °C (39.6 °F) in August 2007.
On the warmest days of the month, the temperature usually reaches around 26.5 °C (80 °F). However, it reached 31.5 °C (88.7 °F) in August 2004.
Precipitation amounts to 105 mm (4.1 in), distributed over 11 days.
The day lasts on average 15 hours and 30 minutes. So the days are long.
There are on average 6.5 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 17.5 °C (63.5 °F). Therefore, the sea is cold for swimming.

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September is generally a mild month. The average temperature is of 12.5 °C (55 °F), with a minimum of 8.6 °C (47.5 °F) and a maximum of 16.4 °C (61.5 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 2.5 °C (36.5 °F). However, it dropped to -1 °C (30.2 °F) in September 1993.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 22 °C (71.5 °F). However, it reached 26.4 °C (79.5 °F) in September 1991.
Precipitation amounts to 80 mm (3.1 in), distributed over 9 days.
The day lasts on average 12 hours and 50 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 38% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 15 °C (59.5 °F). Therefore, the sea is cold for swimming.

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October is generally a quite mild month. The average temperature is of 6.7 °C (44 °F), with a minimum of 3.8 °C (38.9 °F) and a maximum of 9.6 °C (49.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -2.5 °C (27.5 °F). However, it dropped to -8 °C (17.6 °F) in October 1992.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 15.5 °C (60 °F). However, it reached 19.1 °C (66.4 °F) in October 2013.
Precipitation amounts to 90 mm (3.5 in), distributed over 10 days.
The day lasts on average 10 hours and 0 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 31% of the time.
The average humidity is 83%. Hence, the air is normally humid.
The average wind speed is 6 kph (4 mph).
The average sea temperature is of 12 °C (53.5 °F). Therefore, the sea is very cold for swimming.

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November is generally a cold month. The average temperature is of 2.2 °C (36 °F), with a minimum of 0 °C (32 °F) and a maximum of 4.4 °C (39.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -7 °C (19.5 °F). However, it dropped to -12.1 °C (10.2 °F) in November 2010.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 10.5 °C (51 °F). However, it reached 16.1 °C (61 °F) in November 2020.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 days.
The day lasts on average 7 hours and 30 minutes. So the days are short.
There are on average 2 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is 5 kph (3 mph).
The average sea temperature is of 9 °C (48.5 °F). Therefore, the sea is very cold for swimming.

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December is generally a very cold month. The average temperature is of -1.4 °C (29 °F), with a minimum of -3.7 °C (25.3 °F) and a maximum of 0.9 °C (33.6 °F).
On the coldest nights of the month, the temperature usually drops to around -12 °C (10.5 °F). However, it dropped to -19.7 °C (-3.5 °F) in December 2002.
On the warmest days of the month, the temperature usually reaches around 7.5 °C (45 °F). However, it reached 12.6 °C (54.7 °F) in December 1991.
Precipitation amounts to 50 mm (2 in), distributed over 10 days.
The day lasts on average 6 hours and 0 minutes. So the days are short. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 1.5 hours of sunshine per day. So, the sun shines 22% of the time.
The average humidity is 89%. Hence, the air is normally humid.
The average wind speed is 5 kph (3 mph).
The average sea temperature is of 6.5 °C (43.5 °F). Therefore, the sea is very cold for swimming.