Scandinavian Mountains over 2000 metres - James Baxter
Introduction › Climate
The climate of the Scandinavian 2000 metre mountains is typically maritime, and it is strongly influenced by Atlantic weather systems. West weather brings with it the associated fronts, and these are unfortunately the prevailing influence on weather in most westerly ranges like Breheimen and Hurrungane. Rondane is one the very east of the spine of mountains and consequently enjoys more of a continental climate. However, quite frequently a high pressure system over Scandinavia or the Norwegian/North Seas builds and this diverts the progress of the low pressures.
High pressure regularly builds in the spring and late April, and May and early June are often blessed with superb weather. However, night temperatures frequently fall below zero in the higher valleys, especially during periods of high pressure.
By the end of May the main valley floors are usually devoid of snow, but new snow can arrive at any time in May, and above 1500m any time in June also. Unless there has been an exceptionally heavy snowfall in the winter and spring May is the last opportunity to go ski touring or make ski ascents, and June is best avoided as it is a melting limbo-land of snow and bare patches.
The summer weather is more mixed than the usually reliable spring. However, there are at least two long periods where high pressure dominates for at least a week at a time during July and August, giving fantastic conditions in near 24 hour daylight. Temperatures during such conditions may exceed +30 celsius. However, already by the end of August a rogue front could leave some snow on the summits, although this usually melts rapidly.
Summer may rarely also see some thunder storms, usually in the late afternoon and evening. A humming ice axe on the rucksack is telling you to get off the ridge pronto.
If there is a westerly wind during the summer months it normally brings warmer moist air in with it. This travels along the fjords when it is forced to rise, condensing rapidly into a thick mist. If during a summer visit the forecast is only of persistent fronts coming in from the west, which to be fair is not that common, it might be worth considering spending some days in north or east Jotunheimen, or even Rondane, until the weather stabilises again, which it will.
Autumn & Winter
September and October can be fine months but will see the first of the winter storms and established snow on the mountains. By late October the weather deteriorates into snow storms and gales which often persist through to mid March. In addition there are very few hours of daylight.
Most of the snow tends to fall towards the end of winter when the gales are diminishing. This encourages an even snow cover to become established in March for later spring ski tours. The temperature is usually -10 to -15 celsius during winter but may drop to -30 celsius during the few periods of stable high pressure.