The climate of Hammerfest is subarctic, with very cold winters and very cool to quite cold summers.
The town is located on the northern Norwegian coast, in an area of islands and fjords, and about 90 km (55 mi) south-west of the North Cape. Since we are at the 70th parallel, therefore north of the Polar Circle, the sun does not rise (polar night) from November 23rd to January 19th, and does not set (midnight sun) from May 15th to July 30th. The white nights occur as early as April 9 and until September 3.
During the coldest winters, the temperature dropped to -20 °C (-4 °F) in January 1987 and February 2012, and to -21 °C (-6 °F) in January 1999. In summer, the temperature reached 28 °C (-18.5 °F) in July 2014, and 29.3 °C (85 °F) in July 2018.
The average temperature of the coldest month (February) is of -4.4 °C (24 °F), that of the warmest month (July) is of 11.4 °C (52 °F). In summer, there can be cold days, with highs of 8/10 °C (46/50 °F), and milder periods, with highs of 18/20 °C (64.5/68 °F). Here are the average temperatures.

Precipitation amounts to 820 millimeters (32.3 inches) per year: so, it is at an intermediate level. It ranges from 45 mm (1.8 in) in the driest month (May) to 95 mm (3.7 in) in the wettest (October). Here is the average precipitation.

The sea temperature ranges between 5 °C (41 °F) and 10 °C (50 °F). So, it is cold all year round. Despite the latitude, the sea does not freeze even in winter thanks to the Gulf Stream. Here are the average sea temperatures.

Best Time

The best time to visit Hammerfest is the summer, in July and August, since they are the mildest months. However, there are often cloudy skies, some rainy days and a bit of cold.