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.