A Turbulent South-Easterly
7th February 2025
A lovely sunny day in Lochaber today. While not busy, there were a number of teams out climbing on Ben Nevis today. There were also a few teams who had been turned back by a strong South-Eaterly wind. A South-Eastlery wind always seems to be very gusty and turbulent on the Lochaber hills. It also seems to accelerate down the hill, so on a South-Easterly it is often as windy at 600 metres as on the summits. The snowpack is slowly consolidating at most levels with only the tops of the higher gullies creating any cause for concern.

It had been quite cold overnight with a fair bit of ice in many of the puddles and streams on the walk up to the CIC hut.

Looking up Carn Dearg buttress. Notice the spindrift catching the light coming off the top of the buttress, an indicator of strong winds up there.

At time the wind was quite strong, I would say I saw gusts of 60mph walking up from the CIC hut up to Coire na Cistse. There was blowing snow associated with this, as can be seen here coming off trident buttress. However, it felt like most of this blowing snow was dissipating back into the atmosphere, and I certainly didn’t see any significant deposits of fresh windblown snow. Interestingly when I walked down again an hour of so later, winds were light and variable.

The windspeed at the CIC hut for 6 hours up to just before 3pm today. I was walking up to Coire na Ciste about 10.30 where is was gusting 40mph at the hut, when I came came down about midday the wind had dropped right off. Just before 1pm it appears the wind turned back on again. There wind on Tower 17 of the gondola line over on Aonach Mor also showed period of much lighter winds around the same time. Is anyone able to explain this?

The temperature at the CIC hut for the 6 hours up to about 3pm today. It was above freezing for all this time other than from just before midday to around 1pm, the very period that the wind died as shown in the previous graph. I suspect the reason for this is that when the wind died, the air stopped mixing, and the layer within a few tens of meters of the ground was cooled by the cold ground. Also notice how low the wet bulb temperatures are (the lower row of dots), that explains why below the hut then the air temperature was actually above freezing, there was no melting of any snow and ice at that level.
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Sandy
7th February 2025 9:15 pm
The photo looking up to No 3 Gully, is that not No 2 Gully in the centre of the pic?
lochaberadmin
8th February 2025 8:57 am
Hi Sandy, definitely Number 3 Gully.
Chris
8th February 2025 11:27 am
Sandy, number 2 is at the other side of the comb in far left.