A summer day in the meteorological sense is a day on which the maximum daily temperature is 25°C or more. Last Sunday, April 3, was a summer day in Innsbruck with over 26°C. You can literally watch the snow melt - the summer air licks the white off the mountains.
The same effect on a global scale is called ice-albedo feedback. The more ice melts at the poles and glaciers, the lower the Earth's albedo becomes, the warmer it gets and the more ice melts. This is therefore a positive feedback loop; the melting of the ice leads to more and more melting ice. Systems theory knows that positive feedbacks jeopardize the stability of the system and unstable systems break down easily. What this means for the global climate remains to be seen - for fans of snow sports, it means that winter in the Alps below 2500 m is more or less over, at least in three out of four exposures.
Cold front provides some powder sugar
No amount of sugar-coating will help, and neither will the cold front, which caused temperatures to plummet by up to 10 degrees on Monday (4 April) and provided a few centimetres of fresh snow. Initially, the snow line was a good 2500m, then it snowed a little further down during the night. It wasn't more than ankle-deep anywhere, at least if you assume average-sized freeriders and serious measuring methods. Compared to the rest of the winter, it was still quite OK on the north side in places sheltered from the wind, to be fair.
Sunny prospects
The rest of the week will once again be dominated by an area of high pressure over the Alps. Apart from a small disturbance far to the east on Wednesday, it will remain very sunny and Thursday will probably be another "summer day" in some areas. After that, an increasing north-westerly current will cool things down a little with increasingly strong winds. In the Eastern Alps, a few clouds will pass through again on Friday, otherwise it will remain sunny towards the weekend. The longer-term trend also looks like mild weather above average.
