firefly
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Try this out for size...
James Stuart, resident near Braemar, wrote to Lord Fife on the 16th September 1807, saying the following...
"I was very uneasy on Friday the 11th, knowing your Lordship was on the road and as it was very bad....I fear you would be much fatigued....It was a dreadful night in this place....I am told there are about 30 black cattle in Glenavin buried under snow....A great many sheep are also missing....Luckily mine were drove down the woods of Glenquoich and back the day before and are all safe in Glenquoich....They are digging the sheep from under the snow which is blown in some parts more than 10 feet deep....The potatoes are hurt by frost and I fear the green oats will not be seed....The weather is now settled and I hope will continue. "
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Yes, Coaster's Cave snow will be gone by now. A shame, but it still ranks as 2011's most important 'discovery'. The next week or so will be critical, as it looks like there's snow on the way around the 20-21st October. Quite a bit, by the look of the charts.
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A picture from Friday showing the old and new snow on Ben Nevis. The new stuff is pretty ephemeral, and won't be lasting. With mild weather predicted for the next few days, the old snow (whilst not in immediate danger) won't be able to stand sustained mild weather for much more than another 10 days or so. Cold weather is required!
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How deep would the snow be over those patches such as the Sphinx at their deepest (around March)?
This has often been debated, but we've no definitive answers. Depths are notoriously difficult to measure, for a variety of reasons which I won't go into here. However, we do have pretty informed estimates of depths based on winter snow levels against rock formations. These formations can be viewed in summer or autumn when the snow has melted. These are only ever guesses, mind, even though they're likely to be broadly accurate.
My own view is that maximum depths of snow in Scotland are, logically, achieved in the snowiest years (1951, 1967, 1994 etc). In such years, when storms deposit huge amounts in east-facing gullies and hollows, extraordinary depths are achieved. Spindrift posted a link in his post to the 1951 picture of Garbh Choire Mor on Braeriach, and quoted a depth of 20-25 metres in depth. I believe this to be roughly correct. Typically, the greatest depths at the longest-lying patches are achieved are in early spring (late March to mid-April), but there are exceptions. The patches that last longest tend to be around the 3500-3700 feet mark (with the notable exception of Aonach Beag, which lies at barely over 3000 feet), so winter lasts much longer at these locations than even 1000 foot lower altitudes. That's why sometimes a maximum depth is not always achieved until as late as May (Ben Nevis observatory records)!
I suspect that the place in Scotland where maximum depth is achieved is the north-east face of Ben Nevis. Specifically, the upper reaches of Observatory Gully (as per the photo below) will, I would estimate, routinely be around 20 metres deep. In exceptional years, it wouldn't surpise me if the snow was knocking on the door of 30 metres deep.
A discovery of 2011 was 'Coaster's Cave' (below). This hidden gem, located in a side gully off the main Observatory Gully, was measured by me as being 32.3 metres high from floor to 'chimney' opening. This cave fills up with snow completely in winter, and even on the 19th August there was 14.58 metres of depth present. In terms of pure depth, this stands as probably the most consistently deep bit of snow in the western Highlands, and possibly Scotland.
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Spindrift is quite correct. It is most certainly not snow. The flash of the light gives the impression that it's snow, but it isn't!
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Looking at the latest rainfall radar, heavy precipitation seems to be merging around the Nevis / Glencoe area. In addition to the strong NW'ly wind as Firefly mentions above, I think there's a fair chance lasting snow for the winter has arrived here meaning Ob Gully, Point 5, Beag and probably Coasters Cave are home and dry...
Oh, it's much too early to say for certain. It is almost certainly not lasting snow for Aonach Beag. The upper patches on Ben Nevis may have caught a lot of snow (I'll wait for Saturday when I see the evidence), but it's unwise to start saying that the snows are 'home and dry'. Much can change, and remember we're only in early October. In 1994 snow from the previous winter was still melting in December!
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Glencoe looking bleak!
Don't wish to be a pedant, but the hill in the picture is Meall a' Bhuiridh (m-YOUL a VOO-ree), which isn't in Glen Coe!
It's part of the Black Mount, which is complicated by the fact that the area is part of the 'Glencoe' ski area. Confused? -
Winter's here... Cairn Gorm this morning. -2.2 and showers coming in on a very strong NW flow
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The patches will get a fresh covering Thursday / Friday but I don't think this will be lasting snows.
Difficult to say. I fancy that if Ben Nevis gets enough precipitation then the very strong W and NW winds could blow a fair bit down on to the existing snows from last winter. It's amazing how much can build up there in such a short period, given a strong wind. Wind is absolutely crucial in accumulating large amounts of snow in localised hollows and gullies. I'm not saying your wrong, but it wouldn't surprise me in the slightest if we saw some reasonable accumulations over the next day or so.
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It will almost certainly snow heavily (at least for periods) on the high hills of western Scotland over the course of the next 24-36 hours. I would imagine that you'll see some on the webcams in the morning: http://www.highland-instinct.co.uk/webcams/
October snow isn't really that rare. Remember, the first snows of the new season came on the 28th August this year!
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Break it to us then, how did the snow cope with this warm spell.
All the patches that were there last week are still with us, I'm glad to report! However, as you would expect, they've taken a bit of a beating. As I mentioned above, Britain's most durable snow (so named "Sphinx", on Braeriach) is down to a very vulnerable 5 metres wide by 5 metres long. About 1 metre of depth in the middle. It shrunk quite a bit over the last week, but there's still a bit of melting left in it. I visited it yesterday...
This is the only patch in the Cairngorms, and there are several others on Ben Nevis and one on Aonach Beag. Unless we get some sustained cooling and a bit of snow, the Sphinx patch is in real danger of going. The summit temperature yesterday (4200-odd feet) was 8 Celcius. Scandalously warm, given that we're in October. I notice it's a bit cooler today (5 degrees), but really we're looking for temperatures of 2-3 degrees to prevent sustained melting. Not too much to ask on Britain's 3rd highest mountain!
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Well...
This year could very well see something happen that has never happened in the last 100 years. The Sphinx patch, the most durable in Britain, which is in the Garbh Choire Mor of Braeriach, is looking very vulnerable indeed. The warm weather that's forecast for the coming week will, I suspect, reduce the snow to a mere blob no more than a few metres across. If the mild weather endures into next week then it will probably go. Observatory Gully on Ben Nevis, on the other hand, is likely to persist quite a bit longer. This has never happened before. It will still be 10s of metres long at Ob Gully, though the weather in the next 7 days will probably obliterate a good part of it.
There is no old or new snow on Macdui, and the only patch left in the Cairngorms is Sphinx. In the west there are probably 4 or 5 (Aonach Beag, Point 5 Gully on Ben Nevis, Observatory Gully (x3).
Zerouali, there is no such book. Adam is about to publish one that shows the locations and years when snow has survived in Scotland since 1938. I have a copy of it, and it's fascinating stuff! You'll need to wait for it being published, which should be this year some time.
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Firefly
Thanks so much for posting your observations,! The images and the thoughts were in my mind long after I first read your post!
The pictures are really amazing to me, I had no idea that such snow scenes could still be possible at the height of summer (even at that relative high elevation).
Is it possible that the snow/ice buildup in that location (3rd picture) is accumulation over several years? ( Ice upon ice sheet )?
Pleasure! Thanks for the comments.
The snow you're seeing in these photographs is 'new'. That is, snow that fell in late 2010 and early 2011. There are tiny little bits of that patch that have been around since 2006, but they will be at the bottom, and won't be exposed until (I suspect) November. It's possible that we won't see them, as I expect lasting snow will come before they are exposed.
The oldest snow actually visible in Britain just now is a patch here. It is now, strangely, much smaller than we've seen in recent years given the time of year. The snow visible in this photograph fell in 2006.
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For those of you hankering after the first low-level snows of the new season, perhaps a few pictures of the remnants of last year's snow will keep you happy?!
At the start of May I wouldn't have given you odds on any snow remaining on the west coast of Scotland (more specifically, the Ben Nevis range of hills). Summer, though, proved to be a cool, largely wet affair. Like 2007, this preserved the snow remarkably well. As it stands at the moment, there are a few patches left on the Cairngorms, and a few more on Ben Nevis and one on Aonach Beag. The biggest snow by far is at Observatory Gully on Ben Nevis (71 metres long x 30 metres wide x 6 metres maximum depth). You can see the bergschrund of it below (taken Friday 16th).
As has been written elsewhere on these boards, the first snow of the new season has already fallen. This happened on the evening of the 28th August, when NWN winds and cold temperatures brought considerable snow to ground above 3600 ft in the Cairngorms. Such was the scale of the drifting that it persisted fully 12 days, well into September. The longest lying August snowfall since at least 1945 on the hills of Scotland.
If things remain cool into October then I suspect we'll be looking at a few survivals. How many we can expect is not yet clear, but another visit or two into the high hills will be required!
Myself and two friends were up on Ben Nevis on Friday 16th. Pictures and videos are here: http://www.flickr.com/photos/28183399@N03/sets/72157627690205816/
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Last year the first snowfall was in September in the Cairngorms, maybe we could see a repeat? I hope so.
I'm guessing snowfall in June would be considered the last snowfall, while snowfall in August or September would be considered the first.
The first snow-fall of the 2010-2011 season was on the 29th August, not September. This picture by Stuart Gordon was taken on that date, looking towards Ben Macdui in the Cairngorms. There were numerous falls in September, but these tend to be ephemeral.
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Well, as of the 1st July 2011 it was still possible to find a snow-patch in Scotland in the region of 450-500 metres long!
A selection of photographs from the Glenshee area and Ben Nevis range are on my flickr page, here. They were taken as part of the annual 1st July snow-patch survey.
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Both if you have them.
Don't have both in front of me at present, but here are the dates of lasting snow at Scotland's snow-patches:
2007: 4th October (Cairngorms), 13th November (Nevis range)
2008: 1st October (Cairngorms), 20th October (Nevis range)
2009: 1st October (Cairngorms), 5th November (Nevis range)
2010: 20th October (Cairngorms), 3rd November (Nevis range)
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Just wondered if anyone knows whether there has ever been snow in England in July or August and how often it happens and what the lowest ever recorded temperature in those months is?
Heavy snow fell to 500m on Skiddaw (Lake District) on the 11th July 1888. Also, although not fresh snow, in 1979 the last patch to vanish in England was on the 18th August on the Cross Fell range of hills. The chart for the 11th July 1888 can be seen here.
Intriguingly, there were reports of snow falling on that day in London, but I find that almost impossible to believe.
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Sorry, mods! Didn't see this thread when I posted my own one...
Anyway, I see there is some debate as to how likely summer snowfalls are. As I type this, the temperature on top of Cairn Gorm is 0 Celcius, and the rain radar is showing some showers. Almost certainly fresh snow will have fallen overnight. However, snow in June is not unusual on the high tops. June is the third least snowy month in Scotland, beaten by July, and the least snowy month of them all, August.
Adam Watson, a colleague of mine, has been observing the Cairngorms snow for the best part of 70 years. In his time he has seen fresh snow in 12 Julys and 8 Augusts. The total number of days when he has seen no snow in July is 12, and 19 in August. The longest run of dates in either of these months without snow ever being known is 7-13th August and 21-27th August. Fresh snow has been known every other day of the year, including all dates in September and June.
The last time we had fresh snow in August on the Cairngorms was actually last year (2010). It snowed down to 3600 ft on the 28th August.
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First lying dates or lasting snow dates?
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A bit late in coming this year, but I hope the wait will be worth it!
As some of you may have known (or guessed), the very warm April weather decimated the existing snow-patches in England and Wales, and to a lesser extent in Scotland. Couple this with the remarkable lack of snow during the second half of winter and we were looking at the least amount of snow in England at the end of April for quite a few years. Wales fared even poorer, with snow vanishing by the first week of April. Its last snow was on Carnedd Llewelyn.
The snow that did survive in May was, unlike 2010 where it persisted in the Peak District until the 5th, confined to Cross Fell and a few locations in the Lake District. Unlike last year, the honour of having the longest-lying patch in England & Wales fell to Great End, where a wreath persisted until 8th May. I am publishing a paper on this in Weather in a couple of months' time, so keep your eyes peeled if you're a subscriber!
In Scotland, the general level of cover was reasonably average at the end of March. However, April seems to have gotten confused and swapped places with May. As a result, snow was stripped at a rate of knots from lower-lying elevations, so that by the time May came it looked more like the start of June on the hills. May, though, signalled a return to cooler weather. Fresh snow was evident even on the webcams right through the month. So much so, in fact, that the heavy falls of the 16th May were still evident 2 weeks later on Aonach Mor, by Ben Nevis. One local observer reported a net gain of snow in May at the long-lying sites of Aonach Mor.
The cool pattern continued into June, with further falls of snow reported. I myself was up Ben Nevis on the 11th June, and ate my sandwiches on the summit during a snow shower. I cooled my drink in the remains of a drift that had formed overnight in fresh snow.
In terms of the volume of snow that endure at present, we are still behind the game in terms of the last few years. However, the loss we saw in April has most definitely been stymied by the subsequent cool weather. This is very similar to the 'summer' of 2007. There wasn't a huge amount of snow around after winter, but a cool and wet summer meant that big patches survived until winter. Notably at Aonach Beag (920m altitude patch), which was over 50m long at time of new snows.
The next month will be crucial to whether any snow persists through until new falls of autumn. If you'd asked me 6 weeks ago would any survived I'd have said no. However, I'm more optimistic now and have my fingers crossed! As always, keep up-to-date with snow-patches on my flickr site, which is here: http://www.flickr.co...57626414064604/
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I've seen snow melt on Ben Lomond's south face earlier than April before, so nothing exceptional in that. The temperatures, however, are exceptional. Still a wee bit hanging on by the 10th April, according to this picture: http://www.flickr.com/photos/gordonjc/5607818164/sizes/l/in/set-72157626345845137/
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Yup!
I'm the same when I go abroad, if it's any consolation?
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Thanks, Spindrift.
If you want to email me the photographs my address is iainjamescameron@hotmail.com. I'd appreciate a look at them. All observations from southern Scotland and northern England are most welcome.
Glencoe looking bleak!
It's part of the Black Mount, which is complicated by the fact that the area is part of the 'Glencoe' ski area. Confused?
Snow and remaining snow patches
in Spring Weather Discussion
Posted
By-and-large that's true. When we visited Sphinx a couple of weeks ago the top layer was sugary and soft, no doubt due to it being exposed to the rain and warmer air. Below, though, towards the bottom it was like concrete. Really hard. Hardly surprising, though, given that the snow is getting on for 5 years old! Also, these types of patches are made up of avalanche debris and the like, which compacts the snow in winter. This, doubtless, helps the snow resist melting in summer.
Given the mild temperatures of the last week, Sphinx will be critically small by now. It was visited on the 11th and is only a few metres across. Note, the other snow in the picture is avalanche debris from the more recent snow.