Wednesday, February 29, 2012

Less Windy, Cool, Clear

Climbers on Stag Rocks above Loch Avon

Hells Lum and the Feith Bhuidhe

Climbers on Fingers Ridge - Coire an t Sneachda

Ptarmigan still wearing it's winter gear !

Tuesday, February 28, 2012

Dry and Mild

Looking toward Ben Macdui from the SE slopes of Cairngorm.
Coire Raibert and the plateau in the fore ground with the dark cliffs of Carn Etchachan in the centre.

Monday, February 27, 2012

Mild, Windy, Firm Snow!

Coire an Lochain - looking toward twin burns area and the cliffs

Looking at Cairngorm and the Northern Cairngorms from Glenmore
Another mild day with strong winds, snow remains on mainly East aspects, and is hard and compact.

Sunday, February 26, 2012

Snow cover on the plateau

Looking towards Coire Raibert

Snow holes in Coire Raibert

Dropping down Coire Raibert to Loch Avon, full depth glide cracks seen at the top of the snow field, brought about by the thawing conditions.


Jet stream seen in the clouds, winds increased from light to strong in just a few hours.

Saturday, February 25, 2012

Firm under foot

The freezing level rose at midday to around summit level.  
Snow was firm under foot with some very icy patches 

 Patchy snow but still plenty of depth, this Easterly aspect holds over 4 metres of snow in places.

Friday, February 24, 2012

Cooler temperatures today.

The remaining snow is now re-frozen and firm as the freezing level lowered to below the summits.  
Looking towards the Goat track and Fiacaill Buttress.
Coire an Lochian

Thursday, February 23, 2012

Very Wet, Very Windy, Winter?

Coire Chais headwall area
Fiachaill Buttress area Sneachda
Alladdins Buttress and Goat track area Sneachda
Looking Toward Coire an Lochain

Tuesday, February 21, 2012

Mild and wet

If you are standing at the Cas car park staring at the Cairngorms thinking they look a little snowless and bleak at the moment, don't loose heart... With just a bit more walking you will still find some large snowfields on East and South facing slopes, well worth the effort. At the moment some deep, soft accumulations of windslab are going through a consolidation period, however the mild wet weather that we are having is still causing some instabilities, especially on steeper slopes.

Sunday, February 19, 2012

Cloud cleared at midday

Cover on the plateau has improved after yesterdays snowfall. E to S aspects have the best cover.Looking South, drifting on E slopes of Carn Etchachan
Beinn Mheadhoin

Saturday, February 18, 2012

Snowfall with drifting.

Aladdin's Buttress looking wintry, lots of spindrift blowing across the crags.Heavy drifting at the pit, several centimetres of wind slab accumulated within a few minutes.

Thursday, February 16, 2012

Conditions on the hill

Main gully lines in Sneachda holding out, waterfalls were cascading down some of the buttresses, ice looking a bit thin in places. What out for rockfall in the mild temperatures.Flat ice still intact for winter skills

Rain and drizzle cleared by mid afternoon
Coire an Lochain

Monday, February 13, 2012

Poor Viz

I couldnt see anything all day so I took a picture of this rock with some rime ice on it - A mild day zero degrees on the summits, the snowpack is pretty moist, it has refrozen at some point so it is pretty stable.

Friday, February 10, 2012

Avalanche Stories

Avalanche 6th Feb Coire Odhar above Corrour bothy - 2 persons - triggered by 1 person on descent who was carried 200m - all ok - release on weak facet layer
Avalanche report on SAIS Avalanche Mapping Page
Coire Odhar
Crown wall with Feith Bhuidhe and Hells Lum crag beyond - released on weak facet layer.
Avalanche stop point and where they came to rest
General scene
Area of incident 9th Feb 15:00hrs
Over the past couple of weeks or so the snowpack has been affected by the cold air temperatures which has created a temperature gradient in the snowpack, this has resulted in continued development of sugar like, loose grains called facets. Facets are grains that develop in the snow and are associated with shallow snowpacks, they are more frequently observed in countries with a consistent cold weather pattern, eg Alpine, Canada etc.
The weak facet layer has developed between the layers of old firm snow and the newer windslab layer. The windslab layer has been getting harder and firmer while the weak layer below has been getting weaker.
Currently the challenge for anyone going into the hills in the North and South Cairngorms is that there does not seem to be much snow about, therefore considering that an avalanche hazard is possible is not so obvious.
The weak snowpack is very isolated in its distribution and is mainly on East and South-East facing slopes above 900 metres.

In order for the weak layer to disappear it needs to be purged, by weather triggers which provide water to penetrate to it and enable its natural release as an avalanche, or by becoming solid and stable through getting wet with subsequent freezing in cold conditions .
At the moment it is warmer and moist and this layer is in transition, it has been weak and potentially is on its way to improving, we will be monitoring its development.

The following is an account of an avalanche that took place yesterday Thursday 9th Feb and was recounted to me by the the persons involved, it illustrates the conditions described above and is one of a number of avalanches that have taken place in the last week.

Two climbers were returning home after climbing near Shelterstone Crag and where ascending slopes to the south of Hells Lum to the Feith Buidhe. They felt comfortable with the conditions, and had not noted any evidence that made them feel uneasy, the snowpack was firm with a moist surface. At around the 1000 m level they triggered an avalanche and a tension fracture appeared 40m above them, the whole slope broke up into blocks and they were carried down, they stayed on the surface trying to scramble up at first, they went airborne over some small crags, and could see that they were heading toward some cliffs and considered the worst. Fortunately the avalanche stopped 10m short of this cliff. The guys were quite shocked and stated that they would find it difficult trusting any slope in the future because it was so surprising to them. !

The photos illustrate the location and scene

Wednesday, February 08, 2012

Windy with some snowpack instability

Snowpack cracking underfoot on layer of facets NE aspect 1000m
At the snowprofile site
Unstable layers of facetted crystals remain below the windslab and above the old hard snow pack this has been developing in the cold temperatures and strong temperature gradients - go here for info on this

This has produced isolated areas of weak snow with steep N to E aspects and convex terrain above 900m being most affected.

Tuesday, February 07, 2012

Cold an Clear

Loch Etchachan
Ben Macdui and Cairn Toul
Fiachaill Buttress Coire an t Sneachda

Monday, February 06, 2012

White but a thin cover

Looking toward Macdui and Carn Etchachan from Stac an Faraidh

below : Looking West at the Saddle, Strath Nethy and Loch Avon

Sunday, February 05, 2012

Busy day in the Cairngorms

Many people making the most of the snow on the Chais ridge
Lots of routes being done today especially on the buttresses.
Mess of potage looking good, although Jacobs Ladder is full of windslab!

Saturday, February 04, 2012

Weakly bonded windslab

Weakly bonded windslab even down to 750m. This new windslab fractured easily on a softer layer beneath

Friday, February 03, 2012

Cold, sunny and no wind!

Some old avalanche debris and crown wall from last Tuesday on the Chais Headwall
Coire an Sneachda
Wind eroded footprints at windy col
Still thin but improved snow cover on the plateau.