The months of April and May this year were among the warmest on record, according to MeteoSwiss.
The national weather service said the first 11 days of April were particularly warm for that time of year, with parts of southern Switzerland setting a record with some days above 31°C.
On the whole, temperatures were between three and four degrees warmer than the spring average.
MeteoSwiss said March and April, in particular, were too dry, with most parts of the country only receiving 30-50 per cent of the normal amount of spring rainfall.
Not surprisingly, plants and flowers bloomed earlier than usual. The 2011 season came second on the weather service’s vegetation index to the spring of 1961.
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