Despite being located north of the Arctic Circle, Harstad features a sub polar oceanic climate with relatively mild winters and cool summers. Harstad does not have the brutal winters that most locations north of the Arctic Circle experience, and is sheltered from Atlantic gales by a range of mountains to the west. The city actually experiences warmer winters than major cities located 25 to 30 degrees farther south in latitude in the northern hemisphere such as Beijing, Chicago and Toronto. Summers in Harstad are cool, with average high temperatures seldom breaking the 22 �C (72 �F) mark. Mean annual temperature is 3.9 �C (39.0 �F) (1961�90) and annual average precipitation is 850 millimetres (33.5 in). With high pressure weather, winter temperatures can get down to about ?15 �C (5 �F), and in summer they can reach 27 �C (81 �F).
The city enjoys the midnight sun during the summer months, from 22 May to 18 July. There is also a period from early May to early August with twilight for a few hours each night as the sun just dips below the horizon, so there is no darkness. The polar night, when the sun is always below the horizon, lasts from 30 November to 12 January. At this time, there are 3�4 hours of dawn and dusk around noon, sometimes with colourful skies towards the south. From late January, the period of daylight rapidly increases, reaching 12 hours by March and 18 hours in April. Harstad is located in the midst of the aurora borealis (a.k.a. the northern lights) zone, and the aurora can often be seen on clear nights, but not in summer due to the continuous daylight
