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Institute of Physics

The UK shrouded in snow. <em>Picture: NEODAAS/University of Dundee</em>

The UK shrouded in snow. Picture: NEODAAS/University of Dundee

There is no such thing as a standard Scottish winter – but, if there is something approaching a traditional format, one seen more often than others, it is roughly as follows.

First comes wild-and-mild stormy weather in the couple of months before the festive season, but with not much snow apart from on the really high ground, 1,000 metres-plus. Occasional ice and mixed (or messy, or thin, or however you want to label it) conditions on medium-sized hills, and nothing much more serious than overnight frost at lower levels.

January brings the main snow-dumps, with the third week of the month tending to be seen as the critical stretch. Then February settles down into lovely anticyclonic weather, the lower ground starts to feel almost springlike, while the hills – now with a substantial base of January snow – go through freeze-thaw cycles such that everyone is happy and there are great on-hill conditions for walkers, climbers and skiers right through until after the clocks change.

That’s the template, sort of. But by pretty much any assessment, whatever it is we’ve been having this time around, it’s very much not that.

There has been a lopsidedness to proceedings. Late November until early January saw plenty of snow at all levels and disruptively low temperatures. Then the bulk of January was mild and placid, with a retreat of the snowline rather than a bulking-up of the snowpack. And now, the current wave of gales and stormy mayhem notwithstanding, it looks like we could end up viewing this as a wrong-way-round winter, a curiosity rather than a classic.

Or will we? At the start of December, The Caledonian Mercury took soundings from a couple of well-informed people as to how they saw the weather and outdoor-activity prospects over the coming weeks. Now seems a good time to go back and ask for a reassessment.

“It looks like we will be back into a spell of wet, windy and relatively mild weather for the next month or so,” says Alison McLure – former BBC weather reporter, now the national officer for Scotland with the Institute of Physics. “I suppose that will be a relief for the general population, but I miss the stunning clear blue days with crisp snow on the ground.

“I was surprised at how quickly the snow melted from the hills, although hopefully the higher climbing routes will stay in good condition. It feels like we are back to the more ‘normal’ winters of the last 20 years or so. However, if you look into the history of Scotland’s weather and climate, we have lived through a remarkably stable period of weather in recent decades. Professor Alastair Dawson’s book, So Foul and Fair a Day: A History of Scotland’s Weather and Climate, makes fairly gruesome reading, with a litany of storms and extreme cold spells followed by famine. No wonder we Scots are thought of as a dour lot!”

McLure points out that the Met Office has a good explanation of the end-of-year cold spell, with the complex La Niña phenomenon being seen as significant. (La Niña is the counterpart of the better-known el Niño, and results from sustained lower-than-average sea-surface temperatures in the central Pacific. Its effects can be felt worldwide, and it appears to have been a factor in the recent extreme weather in Australia.)

“What I wonder,” McLure says, “is why the weather has returned to a more mobile pattern where we get the mild air off the Atlantic. Has la Niña faded, or have other factors such as sea-ice extent, sea-surface temperatures etc reimposed their influence? Maybe we’ll see a return to colder weather later on. Certainly last year saw a final fling of winter in March.”

In terms of the more localised effects, experienced mountain guide Andy Nisbet suggested in early December that he was “torn between thinking this will be the coldest winter since 1947 (or even colder), or merely cold until some time in January.”

He now sees the latter as much the more likely. “The pattern is similar to 1982,” Nisbet says, “following a very cold autumn 1981 and early January 1982. Not that the winter ended in January, just that only the higher cliffs stayed in good condition. And with plenty of snow in the high Cairngorms at present, there’s no need to feel despondent.

“Atlantic air does seem established, and the Scandinavian high only an optimistic dream. So that’s my prediction: milder than average now, but places like Braeriach and the Northern Cairngorms still good.

“In February 1982, I climbed Ebony Chimney in Coire Bhrochain of Braeriach, one of the best routes I’ve done. Plenty of snow, but also several gentle thaws producing loads of ice which made this deep chimney climb memorable.”

Then there is the skiing. It’s been a great first half to the season, both at the commercial centres and for touring in the forests and on the quieter hills – but what of the lead-up to Easter and beyond? Helen Rennie – one of The Caledonian Mercury’s outdoors people of 2010 – was asked for her thoughts.

Even though she describes herself as “the eternal optimist who will ski on postage-stamp sizes of snow,” Rennie is sure there are some good days ahead, despite the general retreat during January.

“Certainly at Cairngorm the base on the upper part of the mountain has been there since November,” she says. “It has undergone many freeze-thaw cycles and been has repeatedly packed down by the piste machines and skiers, so should be solid enough to withstand some mild weather.

“I’ve kept a log of the days I’ve skied since 1996 when I bought my first season ticket after having my children, as they were both at secondary school then so I had more opportunities to ski. The patterns show that February is usually as good as or better than January, the exceptions being 2001 and 2004. March has always had more ski days that January or February, while April has had more ski days than January apart from 2005.

Rennie mainly skis at Cairngorm. “As for the other resorts,” she says, “I don’t feel quite so confident to predict the future. However, from experience, Nevis Range usually skis well in March and April, as does Glencoe. Glenshee, like Cairngorm, has had an excellent start and the base should be compacted – but it tends to have a shorter season.”

She has put together a five-minute YouTube film of the skiing during 2010 (see end of article). “It certainly brings home what fantastic cover we had over the year,” she says.

For now, though, we’re back into a stormy, unstable flow (a gust of 131mph was recorded on Aonach Mor at 5pm yesterday), with fresh snow being laid down on the middle-to-upper altitudes, but with no clarity as yet as to whether this will quickly be washed away/blown off, or whether some cool-weather stability will create a genuinely wintry February.

At present, the Met Office 30-day prediction doesn’t look promising – talk of settled weather from the middle of the coming week, but also “mild”, “southerly flow”, and “above average temperatures”.

As ever, it remains to be seen. This has certainly been a strange and memorable sequence of seasons, whatever now happens. One remarkable statistic about 2010 – a year that saw two serious winters within one cycle of the calendar – was that five of the 12 months saw temperatures drop to at least minus 18C somewhere in the UK.

That doesn’t happen very often – not since at least the 19th century, it is believed.

The UK shrouded in snow. <em>Picture: NEODAAS/University of Dundee</em>

The UK shrouded in snow. Picture: NEODAAS/University of Dundee

There is no such thing as a standard Scottish winter – but, if there is something approaching a traditional format, one seen more often than others, it is roughly as follows.

First comes wild-and-mild stormy weather in the couple of months before the festive season, but with not much snow apart from on the really high ground, 1,000 metres-plus. Occasional ice and mixed (or messy, or thin, or however you want to label it) conditions on medium-sized hills, and nothing much more serious than overnight frost at lower levels.

January brings the main snow-dumps, with the third week of the month tending to be seen as the critical stretch. Then February settles down into lovely anticyclonic weather, the lower ground starts to feel almost springlike, while the hills – now with a substantial base of January snow – go through freeze-thaw cycles such that everyone is happy and there are great on-hill conditions for walkers, climbers and skiers right through until after the clocks change.

That’s the template, sort of. But by pretty much any assessment, whatever it is we’ve been having this time around, it’s very much not that.

There has been a lopsidedness to proceedings. Late November until early January saw plenty of snow at all levels and disruptively low temperatures. Then the bulk of January was mild and placid, with a retreat of the snowline rather than a bulking-up of the snowpack. And now, the current wave of gales and stormy mayhem notwithstanding, it looks like we could end up viewing this as a wrong-way-round winter, a curiosity rather than a classic.

Or will we? At the start of December, The Caledonian Mercury took soundings from a couple of well-informed people as to how they saw the weather and outdoor-activity prospects over the coming weeks. Now seems a good time to go back and ask for a reassessment.

“It looks like we will be back into a spell of wet, windy and relatively mild weather for the next month or so,” says Alison McLure – former BBC weather reporter, now the national officer for Scotland with the Institute of Physics. “I suppose that will be a relief for the general population, but I miss the stunning clear blue days with crisp snow on the ground.

“I was surprised at how quickly the snow melted from the hills, although hopefully the higher climbing routes will stay in good condition. It feels like we are back to the more ‘normal’ winters of the last 20 years or so. However, if you look into the history of Scotland’s weather and climate, we have lived through a remarkably stable period of weather in recent decades. Professor Alastair Dawson’s book, So Foul and Fair a Day: A History of Scotland’s Weather and Climate, makes fairly gruesome reading, with a litany of storms and extreme cold spells followed by famine. No wonder we Scots are thought of as a dour lot!”

McLure points out that the Met Office has a good explanation of the end-of-year cold spell, with the complex La Niña phenomenon being seen as significant. (La Niña is the counterpart of the better-known el Niño, and results from sustained lower-than-average sea-surface temperatures in the central Pacific. Its effects can be felt worldwide, and it appears to have been a factor in the recent extreme weather in Australia.)

“What I wonder,” McLure says, “is why the weather has returned to a more mobile pattern where we get the mild air off the Atlantic. Has la Niña faded, or have other factors such as sea-ice extent, sea-surface temperatures etc reimposed their influence? Maybe we’ll see a return to colder weather later on. Certainly last year saw a final fling of winter in March.”

In terms of the more localised effects, experienced mountain guide Andy Nisbet suggested in early December that he was “torn between thinking this will be the coldest winter since 1947 (or even colder), or merely cold until some time in January.”

He now sees the latter as much the more likely. “The pattern is similar to 1982,” Nisbet says, “following a very cold autumn 1981 and early January 1982. Not that the winter ended in January, just that only the higher cliffs stayed in good condition. And with plenty of snow in the high Cairngorms at present, there’s no need to feel despondent.

“Atlantic air does seem established, and the Scandinavian high only an optimistic dream. So that’s my prediction: milder than average now, but places like Braeriach and the Northern Cairngorms still good.

“In February 1982, I climbed Ebony Chimney in Coire Bhrochain of Braeriach, one of the best routes I’ve done. Plenty of snow, but also several gentle thaws producing loads of ice which made this deep chimney climb memorable.”

Then there is the skiing. It’s been a great first half to the season, both at the commercial centres and for touring in the forests and on the quieter hills – but what of the lead-up to Easter and beyond? Helen Rennie – one of The Caledonian Mercury’s outdoors people of 2010 – was asked for her thoughts.

Even though she describes herself as “the eternal optimist who will ski on postage-stamp sizes of snow,” Rennie is sure there are some good days ahead, despite the general retreat during January.

“Certainly at Cairngorm the base on the upper part of the mountain has been there since November,” she says. “It has undergone many freeze-thaw cycles and been has repeatedly packed down by the piste machines and skiers, so should be solid enough to withstand some mild weather.

“I’ve kept a log of the days I’ve skied since 1996 when I bought my first season ticket after having my children, as they were both at secondary school then so I had more opportunities to ski. The patterns show that February is usually as good as or better than January, the exceptions being 2001 and 2004. March has always had more ski days that January or February, while April has had more ski days than January apart from 2005.

Rennie mainly skis at Cairngorm. “As for the other resorts,” she says, “I don’t feel quite so confident to predict the future. However, from experience, Nevis Range usually skis well in March and April, as does Glencoe. Glenshee, like Cairngorm, has had an excellent start and the base should be compacted – but it tends to have a shorter season.”

She has put together a five-minute YouTube film of the skiing during 2010 (see end of article). “It certainly brings home what fantastic cover we had over the year,” she says.

For now, though, we’re back into a stormy, unstable flow (a gust of 131mph was recorded on Aonach Mor at 5pm yesterday), with fresh snow being laid down on the middle-to-upper altitudes, but with no clarity as yet as to whether this will quickly be washed away/blown off, or whether some cool-weather stability will create a genuinely wintry February.

At present, the Met Office 30-day prediction doesn’t look promising – talk of settled weather from the middle of the coming week, but also “mild”, “southerly flow”, and “above average temperatures”.

As ever, it remains to be seen. This has certainly been a strange and memorable sequence of seasons, whatever now happens. One remarkable statistic about 2010 – a year that saw two serious winters within one cycle of the calendar – was that five of the 12 months saw temperatures drop to at least minus 18C somewhere in the UK.

That doesn’t happen very often – not since at least the 19th century, it is believed.

A winter trackIf it doesn’t seem long since we were last shovelling snow from pavements and generally skidding around all over the place, that’s because it’s not. There might have been a reasonable summer in between, but the winter of 2009/10 lasted into April, and the 2010/11 edition has started early.

Early Scottish snow isn’t unusual: anyone who ventures out to the hills will be familiar with the on/off nature of “thin” or “mixed” conditions during the couple of months before Christmas. There might not often be much at lower levels, but if you want to find streaks of water-ice, or slithery snow that’s no use to anyone, then the last two months of any year on the Scottish hills are the place to look.

Last winter, for instance, although the cold-clampdown didn’t start until the Sunday before Christmas, the first high-level snows arrived in early October, and other recent years have been similar. What’s strange about this current winter is that January-style snows have swept in two months early. There’s not been much by way of a starter – it’s jumped straight to the main course.

This prompts a question. Will the 2010/11 winter prove to be (a) ferocious for a couple of weeks, followed by relatively mild weather through the critical mid-January period; (b) severe and sustained along the lines of the last one, with all areas and all altitudes affected for several months; or (c) even more severe than that, a mid-November to early May job?

The first people to turn to for cautious predictions are of course the diligent souls at the Met Office. They tend to be mocked for their occasional misjudgements – the 1987 hurricane, the barbecue summer of 2009 – but the bulk of their information is excellent and reasonably accurate.

There’s a rolling 30-day Met Office forecast, divided into four sections, each of which will have a less strong level of confidence: Days 1 to 2 (equating to the daily TV and radio reports), 3 to 5, 6 to 15 and finally 16 to 30 – which at present takes us to the Wednesday between Christmas and New Year. The two shorter-term forecasts talk of continuing snow and ice over considerable parts of the UK. “Remaining cold” is the key phrase.

The longer forecasts are more complex, but continue to paint a wintry picture. “The snow may be heavy at times, especially from the Midlands northwards and also over high ground,” reads the forecast to mid-December – while the 30-day opinion suggests that “… temperatures are likely to continue below average, with widespread frosts, sometimes severe. However, some western and southern parts may be less cold at the start of the period in particular, but still with the risk of further rain, sleet and snow.”

Alison McLure was asked for her thoughts. A keen outdoors person – lots of sailing and hill-going experience – McLure is the national officer in Scotland for the Institute of Physics. She is also remembered as having been Heather the Weather’s predecessor in front of the forecast charts on Reporting Scotland.

“It’s very difficult to forecast accurately much beyond a couple of weeks,” says McLure. “I am also sceptical of anyone who thinks they can forecast beyond this, having been humbled many times as a forecaster. I would go with what the Met Office think, since they are the experts and they are going for it to stay cold until at least Christmas.”

She also offers some thoughts on a more general level. “Being a bit of a dour Scot, it does seem to me to be too good to be true to have two cold winters in a row, especially in a time when temperatures are rising globally. However, there has been research to suggest that Europe gets cooler winters on average when the sun’s magnetic output is low. Solar activity was expected to rise again soon, but doesn’t seem to be happening yet. So, perhaps we will have another cold winter after all.”

Another person keeping a close eye on the situation is Andy Nisbet, a hugely experienced mountain guide based at Boat of Garten. The weather is of particular relevance to Nisbet’s work, but he also has the reputation of being more interested in, and informed about, Scottish winter conditions than pretty much any active hillgoer in the country.

“I’m torn between thinking this will be the coldest winter since 1947 (or even colder),” Nisbet says, “or merely cold until some time in January. Both options are cold, which I’ve been saying all summer.”

He sees similarities with the winter of 1981–82: “I can remember going in to the Garbh Choire bothy [above the west side of the Lairig Ghru] in mid-December and stopping for chips in Keith where the temperature was -12 at midday. It was bitterly cold in the bothy but we climbed an ice route which rarely forms – The Culvert in Garbh Choire Dhaidh. It formed so well because it was early season and the springs were still flowing out into such cold air. Later, we had to walk out in a major blizzard, taking six hours to reach the Sugar Bowl car park in a state of exhaustion.”

It didn’t last, however. “Somewhere around 10 January 1982,” says Nisbet, “it turned much warmer and the winter carried on fairly mild. But that was following on from 1980–81, which was a very mild winter, whereas this time the jetstream is very far south and has been now for some two years.

“If the jetstream stays far south, then it could be like last winter but much colder – the sea temperature is colder, I believe. Last winter wasn’t that cold, but snowy and lasted a long time. If this year is colder, then the Scandinavian High should form and then it really will be cold and make last year seem like a picnic.”

It’s certainly seems likely that the high-level snows will stay for quite a while. They’re being shifted into massive drifts on west-facing slopes, so on that basis another “good” winter seems likely for the skiers, ice climbers and assorted neigeophiles.

But if conditions stay harsh at lower levels, this will have a knock-on effect. Ski centres won’t always be open even when the weather is ideal, and many glen roads leading to interesting hills will be skidpans or worse. January and February of this year saw big hills directly above main roads – Beinn Dorain and Beinn an Dothaidh above the A82 at Bridge of Orchy, for example – being unusually busy due to a general unwillingness to risk minor roads such as Glen Lyon and Glen Lochay.

There could also be the novelty-versus-fatigue factor. A week or two of low-level snow tends to be regarded as fun, even by those who would never dream of venturing beyond the local park for a bit of sledging. But once we’ve had a month of this – once the transport frustrations, fractured wrists and school closures start to mount up – there won’t be much of a feelgood mood.

Nine months ago, after three months of bitter weather, even some hardened winter hillgoers could be heard hankering for a partial, lower-ground onset of spring. But that was in March, with the daylight stretching and the sap beginning to rise. This time we still have the darkest months ahead, so it could prove to be a very long haul.

Ultimately, it’s an educated-guessing game, and we’ll just need to wait and see what happens week-on-week. Alison McLure probably has it right when – displaying a level of diplomacy that would disappoint WikiLeaks – she says: “As an ex-weather forecaster, I would prefer to sit on the fence with this one, but I’ll certainly make the most of the snow while it’s here.”

Some cold-weather thoughts (dated 30 November) from Ewen McCallum, chief meteorologist at the Met Office, can be found here.

A winter trackIf it doesn’t seem long since we were last shovelling snow from pavements and generally skidding around all over the place, that’s because it’s not. There might have been a reasonable summer in between, but the winter of 2009/10 lasted into April, and the 2010/11 edition has started early.

Early Scottish snow isn’t unusual: anyone who ventures out to the hills will be familiar with the on/off nature of “thin” or “mixed” conditions during the couple of months before Christmas. There might not often be much at lower levels, but if you want to find streaks of water-ice, or slithery snow that’s no use to anyone, then the last two months of any year on the Scottish hills are the place to look.

Last winter, for instance, although the cold-clampdown didn’t start until the Sunday before Christmas, the first high-level snows arrived in early October, and other recent years have been similar. What’s strange about this current winter is that January-style snows have swept in two months early. There’s not been much by way of a starter – it’s jumped straight to the main course.

This prompts a question. Will the 2010/11 winter prove to be (a) ferocious for a couple of weeks, followed by relatively mild weather through the critical mid-January period; (b) severe and sustained along the lines of the last one, with all areas and all altitudes affected for several months; or (c) even more severe than that, a mid-November to early May job?

The first people to turn to for cautious predictions are of course the diligent souls at the Met Office. They tend to be mocked for their occasional misjudgements – the 1987 hurricane, the barbecue summer of 2009 – but the bulk of their information is excellent and reasonably accurate.

There’s a rolling 30-day Met Office forecast, divided into four sections, each of which will have a less strong level of confidence: Days 1 to 2 (equating to the daily TV and radio reports), 3 to 5, 6 to 15 and finally 16 to 30 – which at present takes us to the Wednesday between Christmas and New Year. The two shorter-term forecasts talk of continuing snow and ice over considerable parts of the UK. “Remaining cold” is the key phrase.

The longer forecasts are more complex, but continue to paint a wintry picture. “The snow may be heavy at times, especially from the Midlands northwards and also over high ground,” reads the forecast to mid-December – while the 30-day opinion suggests that “… temperatures are likely to continue below average, with widespread frosts, sometimes severe. However, some western and southern parts may be less cold at the start of the period in particular, but still with the risk of further rain, sleet and snow.”

Alison McLure was asked for her thoughts. A keen outdoors person – lots of sailing and hill-going experience – McLure is the national officer in Scotland for the Institute of Physics. She is also remembered as having been Heather the Weather’s predecessor in front of the forecast charts on Reporting Scotland.

“It’s very difficult to forecast accurately much beyond a couple of weeks,” says McLure. “I am also sceptical of anyone who thinks they can forecast beyond this, having been humbled many times as a forecaster. I would go with what the Met Office think, since they are the experts and they are going for it to stay cold until at least Christmas.”

She also offers some thoughts on a more general level. “Being a bit of a dour Scot, it does seem to me to be too good to be true to have two cold winters in a row, especially in a time when temperatures are rising globally. However, there has been research to suggest that Europe gets cooler winters on average when the sun’s magnetic output is low. Solar activity was expected to rise again soon, but doesn’t seem to be happening yet. So, perhaps we will have another cold winter after all.”

Another person keeping a close eye on the situation is Andy Nisbet, a hugely experienced mountain guide based at Boat of Garten. The weather is of particular relevance to Nisbet’s work, but he also has the reputation of being more interested in, and informed about, Scottish winter conditions than pretty much any active hillgoer in the country.

“I’m torn between thinking this will be the coldest winter since 1947 (or even colder),” Nisbet says, “or merely cold until some time in January. Both options are cold, which I’ve been saying all summer.”

He sees similarities with the winter of 1981–82: “I can remember going in to the Garbh Choire bothy [above the west side of the Lairig Ghru] in mid-December and stopping for chips in Keith where the temperature was -12 at midday. It was bitterly cold in the bothy but we climbed an ice route which rarely forms – The Culvert in Garbh Choire Dhaidh. It formed so well because it was early season and the springs were still flowing out into such cold air. Later, we had to walk out in a major blizzard, taking six hours to reach the Sugar Bowl car park in a state of exhaustion.”

It didn’t last, however. “Somewhere around 10 January 1982,” says Nisbet, “it turned much warmer and the winter carried on fairly mild. But that was following on from 1980–81, which was a very mild winter, whereas this time the jetstream is very far south and has been now for some two years.

“If the jetstream stays far south, then it could be like last winter but much colder – the sea temperature is colder, I believe. Last winter wasn’t that cold, but snowy and lasted a long time. If this year is colder, then the Scandinavian High should form and then it really will be cold and make last year seem like a picnic.”

It’s certainly seems likely that the high-level snows will stay for quite a while. They’re being shifted into massive drifts on west-facing slopes, so on that basis another “good” winter seems likely for the skiers, ice climbers and assorted neigeophiles.

But if conditions stay harsh at lower levels, this will have a knock-on effect. Ski centres won’t always be open even when the weather is ideal, and many glen roads leading to interesting hills will be skidpans or worse. January and February of this year saw big hills directly above main roads – Beinn Dorain and Beinn an Dothaidh above the A82 at Bridge of Orchy, for example – being unusually busy due to a general unwillingness to risk minor roads such as Glen Lyon and Glen Lochay.

There could also be the novelty-versus-fatigue factor. A week or two of low-level snow tends to be regarded as fun, even by those who would never dream of venturing beyond the local park for a bit of sledging. But once we’ve had a month of this – once the transport frustrations, fractured wrists and school closures start to mount up – there won’t be much of a feelgood mood.

Nine months ago, after three months of bitter weather, even some hardened winter hillgoers could be heard hankering for a partial, lower-ground onset of spring. But that was in March, with the daylight stretching and the sap beginning to rise. This time we still have the darkest months ahead, so it could prove to be a very long haul.

Ultimately, it’s an educated-guessing game, and we’ll just need to wait and see what happens week-on-week. Alison McLure probably has it right when – displaying a level of diplomacy that would disappoint WikiLeaks – she says: “As an ex-weather forecaster, I would prefer to sit on the fence with this one, but I’ll certainly make the most of the snow while it’s here.”

Some cold-weather thoughts (dated 30 November) from Ewen McCallum, chief meteorologist at the Met Office, can be found here.