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.
The patch at Garbh Choire Mor on Braeriach in the Cairngorms is believed to have 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.
Dr Adam Watson, a biologist dubbed Mr Cairngorms because of his years studying the mountains, has written of the snow at Garbh Choire Mor.
His research of snow lying there for years drew on information handed down by generations of stalkers and families that had worked in that area.
In a post on Twitter following a visit to Garbh Choire Mor, Stirling-based Mr Cameron wrote: "Sphinx has a matter of days left. I'm displeased."
The Sphinx is one of only two patches of snow surviving in Scotland's hills this year.
The second patch at Aonach Beag is also expected to melt away over the next few days, said Mr Cameron, whose records of snow patches are published by the Royal Meteorological Society.
In August, Mr Cameron reported that for the first time in 11 years there was no snow on Britain's highest mountain, Ben Nevis.
Garbh Choire Mor is described as Scotland's snowiest corrie because of the amount of snow it can hold even through summer months. Corries are a hollow-shaped geological features found high in Scotland's mountains.
UKClimbing.com describes Garbh Choire Mor as "remote" and having an "alpine feel".
It also warns that it is a place to avoid in winter because of cornices, large overhanging ledges of snow, that form above the corrie.
The snow patch that has so far survived on Aonach Beag was skied on earlier this month by Helen Rennie, who has skied on natural Scottish snow every consecutive month for almost eight years.
September's visit to Aonach Beag for BBC Radio Scotland's Brainwaves programme was the Inverness-based skier's 95th month.