According to the BBC:

Scotland’s longest lasting patch of snow could melt away by the weekend.
Iain Cameron, who seeks out and records snow that survives on Scotland’s highest mountains, believes the patch known as the Sphinx has days left.
Scientists say the patch at Garbh Choire Mor on Braeriach in the Cairngorms has disappeared only six times previously in the last 300 years.
According to records, the snow previously melted in 1933, 1953, 1959, 1996, 2003 and 2006.

Full article here.