Sion
© Le NouvellisteSion, Switzerland
Police in the canton of Valais have warned skiers to keep on the marked runs as the avalanche risk rises to 3 or 4 out of 5 in resorts across the region.

Valais has experienced some of the heaviest December snowfall in years over the last few days, not just in the mountains but down to the valley floor.

Sion, the cantonal capital, received a record 65cms of snow over the weekend, and pictures published by local paper Le Nouvelliste showed residents skiing down the streets. Around 80cms fell at higher altitude.

While most of Switzerland experienced some snow on the weekend, temperatures warmed up on Sunday afternoon turning the precipitation to rain in many places, however the particular meteorological conditions in the Valais meant it kept snowing.

Sion, Switerland
© Le Nouvelliste‏Sion, Switerland
"It's what I call the Valais miracle, when cold air is trapped in the valley although there's a thaw at altitude," meteorologist Frederic Glassey told news agency ATS.

The weather played havoc on the roads, leaving some 2,000 motorists stuck on the A9 motorway. Strong winds meant snow was even carried into road tunnels, said Glassey.

On Tuesday Valais police warned people against walking in forests, saying trees have been weakened by the snowfall and the subsequent thaw, meaning there's a risk of some falling.

Skiers should stick to the pistes since "the few days following snowfall are the most dangerous" for avalanches, police warned.

However conditions for skiers who stay on the marked slopes are likely to be incredible.

It's certainly a change from last year when Switzerland experienced its driest December for 150 years.