Mild and damp on Aonach Mor

A misty, damp and mild day on Aonach Mor. There is still good snow cover above around 900m on NE to SE facing slopes but the snowpack is moist or wet - it would be great to have some freezing conditions.

This is today's view of the North end of the Coire an Lochain crags from the "Climbers' Col".

The mild conditions continued today. The snowpack is gradually consolidating in the warm temperatures. The greatest hazard on Ben Nevis today was being hit by collapsing snow and ice. Saturated cornices are prone to spontaneous collapse. Observatory gully was filled with small shards of ice (see top picture). These are the remains of bigger chunks that have fallen of the crags during the past few days. The bottom pictures shows that there is some ice left on the crags around Point Five Gully.

Freezing rain on Aonach Mor

Another day with poor visibility on Aonach Mor. This is a view from the cairn at 1000m on Aonach an Nid looking south up the ridge.

Today's summit air temperature was at or just below freezing. The falling rain was freezing on contact with the ground, clothing, ropes, etc. A thin surface layer of rime was present on the snowpack above c1000m.

The freezing level was hovering around the 1200m mark today, with a thin crust on the snow surface at higher elevations. A few teams out on Aonach Mor doing various routes today. The snow conditions did not look as good as they were a couple of days ago. Despite the thaw, there is still plenty of snow around. Below is a photo of a winter skills group at around 850m.

Not a great deal happened today from a snow and avalanche point of view. In the continuing cold conditions the snowpack is slowly consolidating. The cloud base was generally about 1000m today, and this meant that we did not get a view of the crags on Aonach Mor. I imagine they are looking pretty white though. The picture shows a group practising winter skills at about 950m on the back of Aonach Mor. As can be seen there is lots of snow in some locations in the West Coast at the moment.

Visibility was very poor on the summits this morning (although it is clearing up now). Thick cloud like this really encourages the formation of hoar frost. Hoar frost forms on the wind ward side of objects. This is because the cloud consists of microscopic droplets of super cooled water. When these get blown onto surfaces they freeze on impact. Over time this process builds up a thick layer of snowy/icy material. Todays picture shows a hut on Aonach Mor looking fairly plastered in hoar

Up the Ben

Good amounts of snow up the Ben today, although virtually no fresh. Most of the snowpack has a very thin rime crust on the surface which has helped stability considerably. It still makes for some hard work when it comes to trail breaking though!
Quite a few teams out climbing today. Mass ascent of Ledge Route and quite a bit of activity on Carn Dearg Buttress. Photos to follow.....

View from Aonach Mor today.

Has anyone seen any avalanche activity up the Ben over the last few days? Please feel free to email me any details..

At last, a cloud free day on the summits. Cold with some fresh snowfall overnight. The NE wind has moved some of the soft windslab from yesterday. Most of the crags look plastered. Fab off-piste skiing today!

View up towards the crags on Aonach Mor.

Here is a shot of the shear that was obtained in the snowpit today. The bonding is inproving but the slab still pulls out in a fairly cohesive lump. It is sliding on a fairly thin melt-freeze crust that was formed a couple of nights ago.

A wild morning with some heavy snow showers. The picture shows an observer on an exposed ridge at an altitude of about 1000m. Large amounts of snow were being blown along the ground (note that you can't see the observers feet). This blown snow would form cornices and deposit windslab on lee slopes.

Back to trad conditions today. Come late afternoon, the freezing level had risen to around 1200m. Looks like it will get cold again overnight and the strong winds will ease durnng the day.

After inital snow it turned out to be a pleasant day on Aonach Mor. As this picture looking over to Carn Mor Dearg and Ben Nevis shows, there is a fair bit of snow on high North and East aspects. There is ice building in the gullies and on the crags for climbers, and some fresh snow for skiers. However some caution is needed with all this fresh snow around.

A wild day on the hill today. Strong winds and blowing snow made observing conditions difficult. More of the same is expected tomorrow.

Winter Wonderland

You couldn't complain much about the conditions today (unless you were a skier). Good Neve everywhere, virtually no wind and even the odd glimpse of sunshine. "The best climbing conditions in years" said one team we met. Anyway here are a few pics of the crags to give you an idea.:

Ben Nevis from the summit of Aonach Mor

Crags on Aonach Mor

Blair investigating the crevase at the cornice above Easy Gully

Blair relaxing inside the crevase!

Today was a wash- out. Need I say more....

Anyway, winter is coming back tonight. The wet snow will turn into Neve, some light powder on top and the sun will come out. Pack your sunglasses for tomorrow. (my forcast may not be 100% accurate!)

Just to prove that it does actually snow up here, this is Keith standing in fresh snowfall at about 800m today:

However, just after this moment in time, the freezing level rose above the summits again.
Tommorow looks like a washout again, but possibly looking more promising by tomorrow night.

Wet again

The freezing level rose very quickly this morning to bring rain to all levels by about 10am. Looks like it will snow overnight and then rain again tomorrow. WInds are going to stay on the strong side.

It all sounds like quite a good excuse to have a long lie tomorrow morning. While you are all doing that, I will no doubt be hiking up the Ben again!

Here is a photo of Aonach Mor at lunchtime, proving there is no new snow left!

Interpreting Snow Profiles

I thought it would be useful to try to give some assistance in interpreting the Snow Profiles that you will see now and again on the Blog.

These are prepared on a daily basis at a representative location of the current snow conditions. They are generally only dug down to the first stable layer. When I feel it is useful, I will post these on the Blog for all to see.

There now follows a key to all the symbols and their meanings. The symbols used are all Internationally recognised so once you get the hang of it here, you should be able to read these graphs anywhere.

Click here for the full text of the International Classification

I shall work through an example of a surface profile and summarise the important points in the International Classification: First of all, lets look at the following snow profile:

The top section should be fairly self explanitory, however you should note that the Met Conditions are the mid day readings from the summit of Aonach Mor and the wind is a 24 hour vector average. The met conditions at the pit site are started in the comments. This is how it is recorded in Lochaber, other areas may do it differently.

Now looking at the graph, taking things from left to right:

Comments: This normally is used to record any shears in the snowpack. Here we use 2 main tests, the Shovel Test and the Rutshblock Test. Thus ES means an easy failure with a shovel test. WRB3 means a failure 3 with a walking rutchblock test. A walking rutshblocktest is an adaptation of the standard rutshblock test. The block size is approx 1m by 1m and you don't use skis. Click on this link for a description of the Rutshblock Test. Subsitute the new size and read boot every time it mentions ski in the description.

F: This is the international symbol for Snow Crystal Tipe. Summary info is given below. For more info, click on the International Classification link above.

E: This is simply the snow crystal diameter in mm.

R: This is the snow hardness. In the field, we measure this with a simple hand test. It is recorded on the form using the international symbols:













θ: This is the symbol for water content as follows:

To the right hand side, there is a pictorial representation of the different hardnesses for each layer (scale along the bottom). Superimposed on top of this is the temperature profile of the snowpack (scale along the top).

So there it is in a nutshell. Hopefully you will be able to make better sense of it all now!

Today was a really wet day on the hill. Strong winds, heavy rain and mild temperatures have saturated the snowpack. The cornices above many routes on Aonach Mor on Ben Nevis are quite unstable at the moment. The forecast is for cooler temperature tomorrow. These stormy freeze thaw cycles are likely to be forming lots of ice high on Ben Nevis.

Pretty wild day on the Ben today. Not many folk about at all!

Winds were blowing over 100mph on the summits and the freezing level gradually rose to around the summits.

We are expecting more snow tonight before a major thaw tomorrow.

Tomorrow, it doesnt sound worth getting out of bed for - heavy rain and very strong winds again.

Saturday looks better.....

There has been a light dusting of fresh snow but no significant accumulations. All the exposed old snow has started to refreeze and gives good cramponing practice on the plateau. Old snow on the crags should be be good but I have not tested it!

Vis was poor this morning but after we left the hill, the clouds lifted - typical.

Photo today is of some folk heading down Easy Gully this morning.

Last night the temperature shot up (5°C was recorded on the summit of Aonach Mor) and heavy rain fell. The snow that has accumulated in the past few days became very unstable. We saw debris from five avalanches on Ben Nevis. These would have released naturally during the night. The picture shows the debris of largest of these. This was at long avalanche. The release zone would probably be in Tower Gully (altitude 1300m). The avalanche decended Observatory Gully with debris down, well past the base of Observatory Ridge, to an altitude of about 900m. The other picture shows the base of Zero Gully/Orion Face. Although it was melting rapidly today, if it freezes tonight as forecast conditions will improve.

There seems to have been a brief warming last night before further snowfall and colder temperatures this morning. Much of the fresh snowpack has a very thin wet , crusty layer within it but this is not really adding to stability. Went in to the top of Easy Gully today on Aonach Mor. There was evidence of several surface releases on the East aspect at the top of the gully. The new snow sheared fairly easily in several places - see photo and surface pit graph(click to enlarge!) Looks like tomorrow afternoon is going to be warm again. This should bring a period of instability, with wet snow avalanches likely where the existing slab is present

The were some heavy showers today, which fell as snow above about 700m. Alot of this snow was blown into the gullies and onto scarp slopes. A few brave souls were seen heading down Easy Gully on Aonach Mor, where there looked to be alot of fresh windslab. There are now large cornices above many of the routes at Aonach Mor. One leader seemed very grateful to have a rope dropped to him for the top out around Forgotten Twin.

The freezing level dropped to around summit level today. The snowpack in general is still very wet, but with a thin icy crust at the highest levels. Here the crown wall, and debris, from an avalanche which occured on Aonach Mor during Wedensday (caused by a cornice collapse) is investigated.

Not much change out there from yesterday, except that the rain hs gone off.
Might get slightly cooler over the next few days but I wouldn't put much money on it..
Still loads of snow etc left in the gullies and a freeze now would be superb though unlikely!

Mild temperatures (+4°C on the summits) and rain produced a period of instability during the early hours of Wedensday morning. Numerous avalanches released naturally during this period. Here an observer investigates debris below Number Two Gully on Ben Nevis.

Quite a bit of fresh snow around up there now, although visibility this morning above 1000m was particularly poor.

Managed to get into Easy Gully, Aonach Mor (see photo) There had been several natural avalanches in here recently, with another soft slab release triggered by the cornice as we entered. You can see the end of the crown wall in the phto running down towards the pit.
Have included a picture of the surface pit from today, which clearly shows the 2 weaknesses within the snowpack. There was 120cm of fresh snow on top of the old snow layer.
Looks like it is all going to fall down tomorrow are a band of wet and windy weather crosses the area

Happy New Year!

Wild day on the tops today. Above is the best photo of the day: Geoff trying to be dynamic whilst negotiating the cornice at the top of Left Twin on Aonach Mor.

There is quite a bit of new snow now in the corries. Most of the day, the snow showers have been persisting and the winds have been fairly strong westerlies. On the summit this morning, they were blowing around 60 mph

The diagram below shows the surface pit from today, it was dug at the top of Left Twin on Aonach Mor. For those unfamiliar with the area, this is an easterly aspect at 1190m, just below the plateau cornice. As you can see, there is quite a depth of new snow with some fairly easy shears towards the top.