Some professions are susceptible to superstition. At its most extreme, miners and fishermen know that their fate is only partly in their hands and that their lives, let alone their prosperity, are in the hands of forces that are bigger than them and implacable and unknowable. Sportsmen and women have their superstitions about what they need to do to win. Politicians, particularly those at the sharp end fighting for their seats, are equally at the mercy of events and look for every bit of folk wisdom they can find. There have always been beliefs about what the weather might mean for the political parties. The 2019 election is close enough to the end that polling day, 12 December, is now within the range for which meteorologists will hazard an estimate.

The forecast is, unsurprisingly for a December day in the UK, for some thoroughly grotty weather. Manchester and Glasgow will have snow and temperatures hovering near zero. London and the south are a bit warmer, but the precipitation will be liquid and getting around will probably be even more depressing and uncomfortable. 

The bad weather will chill the hearts of Labour supporters. The folklore is that good weather is better for Labour. Neil Kinnock alluded to this belief in 1992, when he quipped ‘the sun’s out, and so are the Tories.’ The result of that election, though, shows the extent to which one can rely on these folkways. Good weather is supposed to encourage high turnout because the marginal, unenthusiastic voter will saunter down to the polling station if the sun is out but be reluctant to face the wind and the rain out of civic duty. Historically, there has also been a strong belief that people who cast their votes at different times of day have different political leanings – that the pensioners and mums who vote during the day lean Tory but the Labour vote fights back when the men who come off shift at 5pm or 6pm stream to the polls. There is a reasonable case to be made that the October 1964 election result was affected by polling day weather – the heavy rain in the afternoon may well have dampened Labour turnout by enough to reduce the majority from a small but workable level to a perilously tight margin of 5 seats that necessitated another election 18 months later.

One way of resolving your voting dilemma is to blame the icy road and stay indoors

But do any of these rules still apply? Certainly, what happened in 1964 cannot be repeated. The gender gap in voting behaviour among working-age people has reversed, workforces are more balanced, and there are many fewer places where huge numbers of people clock off work at the same time and then go to vote. But how does it stack up given the political divides and social patterns that exist in 2019?

We can be sure that many more people vote by post than did in previous bad-weather elections. These people are therefore immune from the effects of polling day weather. These people are more likely to vote Conservative than Labour, despite some conspiratorial beliefs widely held on the right. Chalk one up to the Tories.

However, horrible weather on election day is more likely to be a deterrent to some Conservative-leaning sections of the electorate. Older people are less likely to go out, and the parties are less likely to be able to provide lifts to the polls, which in the 1950s was regarded as a secret weapon worthy of strict regulation. The further apart polling places are situated, the more likely the marginal voter is to not bother. This will affect rural areas, and the more sparsely populated suburbs. Chalk one up to Labour.

But what about campaigning leading up to polling day? As I have been meeting campaigners, it has become clear how much a December election disrupts the way elections are fought. The hours of darkness descend before many people have got home from work, rendering a higher proportion of voters than normal inaccessible to doorstep campaigning. Party volunteers may be less willing to come out on the doorstep anyway, although on a cold clear day on the England-Wales border there seemed to be no shortage of activists. Parties that depend on traditional campaigning and face to face contact therefore should lose out, while parties that rely on online propaganda, high-tech demographic targeting and paid-for mailshots should do better. Two-one to the Conservatives.

But the ultimate effect will depend on something that is still hard to know – how determined are the voters on each side? If you are cross-pressured, a hitherto Labour Leaver or a disgruntled Conservative Remainer, one way of resolving your dilemma is not to commit yourself, and tell yourself that you would have voted but there was ice on the road or the buses back from work were difficult and it was too late… But even so, who will that affect more: the people who vote for their own side with a clothes-peg on their nose, or those who had half-decided to cross over? The conventional wisdom was that Labour voters were more easily deterred by bad weather, but with support for the two main parties being driven by loathing for the other side, or weariness at politics itself, how would a negative, reluctant vote be affected by whether it is nice out?

Weather is only the smallest of nudges to an election result; it is dominated by all the more orthodox considerations that feed into electoral choice. But the tantalising thing is that there are too few general elections to really be able to say anything statistically reliable about how it does affect choice, and that we cannot rule out some combination of weather and political sociology from making it an important consideration in future. It is not surprising that weather-related superstitions still have influence over nervous campaigners.