Usually, snow in the Canary Islands doesn't last long because the cold air that allows it to settle blows away quickly and the Sun melts it away. This causes its own problems as lots of locals get excited and drive up into the mountains to take advantage of this unusual event.
Does Tenerife have snow?
Temperatures reach highs of 21.1°C on average, but locations at altitude will tend to experience temperatures in the single figures in January and the sight of snow on Mount Teide is not uncommon.