In Longyearbyen, the average temperature ranges from -14°C during the winter to +6°C during the summer. The very lowest temperature was measured in March 1986 at –46.3°C, while the very highest temperature was measured in July 1979 at +21.3°C. It is not uncommon on Svalbard to have long periods during the winter with temperatures between –20 and –30 °C; add to that a wind-chill factor that usually seriously compounds the cooling effect of the low temperatures. Periods of fog are common during the summer. In terms of precipitation, however, Svalbard may be described as an ”Arctic desert” with annual rain- and snowfall at a mere 200-300 mm. The weather on Svalbard can shift very quickly, and local variations are often considerable.
Light winter (March – May)
As the light returns, the activity level and amount of energy increase. Everyone wants to get out, to see and to explore! March through May is an exciting time on Svalbard. The days become increasingly longer, and by the end of April, the midnight sun has returned to warm a wintry landscape. The migrating birds start returning, the mountain sides are filled with bustling life, and the seals enjoy the rays of sunshine on the fjord ice. Facing the spectacular blue-green glacier fronts invite you to inner reflection. This time of year is ideal for outdoor activities and wilderness adventures.
Summer (June – August)
The snow disappears, small flowers blossom, and a rush of bird activity replace the quiet of winter. This is summertime on Svalbard. Mountains, valleys, glaciers, the sea, flowers, animals and birds attract you to adventures you will never forget. The summer in the Arctic region is short and hectic. Even with daylight around the clock, the days never seem long enough to fit everything you want to get done.
Autumn (September – October)
The landscape dons its autumn frock when orange colours cover valleys and mountains while the topsoil slowly freezes. Temperatures sink down toward zero. Gradually, the days become shorter, and suddenly one morning you wake up to find that the sky has sprinkled a layer of white frosting over the mountain peaks. Hikes at this time of year leave lasting memories. The frozen topsoil is easy to walk on, the air is pure, and a reddish-orange evening sun is on display in all its glory.
Winter and polar night (November – February)
By the end of October, the sun has sent its final rays for the year over the landscape, and Svalbard enters into a period of darkness. For more than two months, from mid- November to the beginning of February, darkness prevails around the clock. Yet when the weather is good, the moon is full, the skies are starry and the Northern Lights are dancing, it is possible to experience the characteristic blue lights that characterise polar nights. Many find the month of February the most beautiful month of the year. The polar night gives way to the rising sun, inching higher and higher for each passing day. On a clear day, the sky’s many blue hues blend with a shade of pink – and finally the day comes when the first pink rays from the sun touch the mountain peaks. After starting at the top, the sun gradually makes its way down the valley. At this time of the year, the area is filled with a unique atmosphere and mood which simply must be experienced.
The Polar Night
During the period between November 14th and January 29th, a very special phenomenon occurs in Svalbard; The Polar Night. During the Polar Night the archipelago is blacked out, and you can tell no difference between day and night. The phenomenon of Polar night is caused by the sun being more than 6 degrees below the horizon. During the periods between October 26th to November 14th and January 29th to February 14th, the sun still is below the horizon, but the light from the sun reaches over the horizon and gives us a twilight period.
The Northern Lights (Aurora Borealis) is beautiful, fascinating and mythical. The sky is filled with moving colors of green, pink and purple. On Svalbard, during the dark period, you can see the northern lights even at daytime. This makes Svalbard a suited place for northern lights research.
Read more about northern lights and research here:
Les mer om Nordlys og nordlysforskning her: http://www.eiscat.se/
The Midnight Sun
Longyearbyen has midnight sun from April 15th to August 26th. In contrast from the midnight sun in Northern Norway, which is quite low above the horizon, the midnight sun in Longyearbyen is high in the sky and makes it hard to tell night from day.