Has Scottish economy actually been derailed by wrong kind of winter?

Bank of Scotland, publishing its latest survey of private sector output north of the Border on Monday, appeared at pains to explain away the economy having slammed back into reverse by citing "severe weather".

However, while January was a bit busier on the weather front after a quiet start to the winter with some strong winds, a bit of snow and freezing temperatures, overall conditions hardly seemed extreme. Remember the protracted Arctic spell during the winter of 2010/11? Did last month really feel like that for people in most of the country? You would imagine not.

Surely no-one was hoping for temperatures of 70 degrees Fahrenheit with bright sunshine and not a breath of wind. Hopefully, no-one cancelled their winter sun break to the Canaries on the basis of such an expectation.

In any case, the Bank of Scotland PMI (purchasing managers' index) report, compiled by financial information company Markit, is adjusted for seasonal factors.

That is not to say that weather played absolutely no part in the reverse. Bank of Scotland cited "mentions among panellists" in both the services and manufacturing sectors of "adverse weather disrupting activity".

However, given January did not appear that wild on the weather front and the seasonal adjustment of the survey findings, the assertion that weather was a crucial factor could be viewed as somewhat Panglossian.

It might be worth observing, in this context, that Glasgow and Edinburgh airports reported strong year-on-year growth in passenger numbers in January. So it was hardly as if the country ground to a halt.

The Scottish Retail Consortium, in a survey published today, reveals shopper footfall north of the Border in January was down by three per cent on the same month of last year. Shopping centres and high streets saw year-on-year drops in footfall, although out-of-town retail locations fared better.

What is most interesting about the SRC report, conducted in conjunction with customer counting specialist Springboard, is that the "bad" and "severe" weather highlighted in the Bank of Scotland survey is not flagged as a factor in the decline in footfall experienced by retailers last month.

In short, the tumble in the headline PMI for Scotland, from 52.8 in December to 47.7 in January, is a bit alarming. This fall took the index, a timely and closely-watched indicator of economic activity in Scotland, significantly below the level of 50 deemed to separate expansion from contraction. Both manufacturing and services fell from expansionary to contractionary territory.

Monthly surveys can have a degree of volatility, but such dramatic movements in the Bank of Scotland PMI are unusual. It will be interesting to see the survey findings for February.

Talking of Panglossian, Bank of Scotland was put in the shade yesterday by Mark Carney, as the Bank of England Governor gave an assessment of the UK economy with which the famously upbeat fictional character, Pollyanna, would probably have been well satisfied.

In spite of the domestic and international headwinds facing the UK economy, the Bank of England raised its growth projection, citing the beneficial impact on squeezed household incomes of the fall in oil and wider energy prices. It now expects UK economic growth of 2.9 per cent both this year and in 2016. It had previously projected 2016 expansion of 2.6 per cent. The 2015 forecast is unchanged from November, in spite of the recent slowdown in UK economic growth.

The Old Lady of Threadneedle Street's latest assessment of the position of, and prospects for, the UK economy will be read by many with particular interest, given the proximity of the General Election.

The Bank appears surprisingly optimistic on the prospects for pay growth in the UK. Average weekly earnings are forecast to rise by 3.5 per cent this year, double the 1.75 per cent rate of increase in 2014. The Bank has come to this upbeat view even though earnings growth has consistently proved lamentably weak in recent years.

Mr Carney highlighted the Bank of England's "fairly robust outlook" for consumer spending, but emphasised that this would, in the Old Lady's view, not be "debt-fuelled expansion".

Figures published last month by the Office for National Statistics showed annual UK consumer prices index inflation had plunged in December to 0.5 per cent - its joint-lowest since comparable records began in 1989.

Mr Carney said yesterday that annual CPI inflation could potentially turn negative in the spring, and be close to zero for the remainder of the year.

It is interesting that both he and Chancellor George Osborne have been at pains to claim such a scenario would not really constitute deflation.

However, this really is splitting hairs. If general prices are falling, you could certainly argue we have deflation.

We should remember that the Bank of England's target of two per cent for annual CPI inflation is symmetrical. A rate below this level is, according to the way the target is set, as bad as a differential of equal magnitude in the opposite direction.

However, Mr Carney appears unperturbed with the notion of temporary negative inflation, or deflation as some others might characterise it.

Indeed, there even seemed to be a hint of enthusiasm about inflation being way below target in his latest comments.

He said: "We're going to have a period where headline inflation is low - very low - for most of this year, and that's a good thing in general because of the causes of it."

In terms of causes, Mr Carney highlighted the tumble in energy prices.

At least he did acknowledge that very low inflation was "not a good thing if it persists". But never mind the wrong kind of snow, now it appears we can have the right sort of far below-target, or even negative, inflation.

Given the challenges facing the UK economy as the election looms, Mr Carney appeared surprisingly Panglossian. He seems to believe the UK economy is on the right track. But he and Mr Osborne should watch out for leaves on the line.