This is not my attempt at putting an original slant on a short-term weather forecast for North Germany, although it would be rash to discount the possibility of a spot of rain.

It is rather a reflection of the latest in a long stream of initiatives being devised in this Olympic candidate-city in a bid to ensure that the dream of bringing the 2024 Games to the banks of the Elbe endures beyond this month.

By the time we open the first window of our Advent calendars, we should know whether the project, recently costed at €11.2 billion (£8.2 billion/$12.5 billion), has survived a referendum among local people clearing the Hamburg bid team to press on in this high-stakes international contest pitting them against Budapest, Los Angeles, Paris and Rome.

The poll, in which postal voting is being encouraged and is expected to be prevalent, is of major significance, plainly, for this proudly independent port-city of 1.8 million.

But it is also enormously important for the Olympic Movement which has looked on in baffled/horrified/hurt amazement in recent times as a long line of cities, including St Moritz/Davos, Munich, Kraków, Stockholm, Oslo and Boston, have turned their backs in one way or another on the chance of hosting an Olympic Games.

If Hamburg adds its name to the list, it would make it hard to see how the Games could possibly be staged in the country of current International Olympic Committee (IOC) President Thomas Bach for the foreseeable future, while also diminishing the 2024 field at an unfortunately early point in proceedings and possibly increasing pressure for the other three European candidate-cities to hold referenda themselves.

On this occasion though, while it would be unwise for sports leaders to start counting chickens just yet, there are signs that a Yes vote, on a sufficiently high turnout of inhabitants, may be achievable, with a recent German Olympic Sports Confederation (DOSB) survey putting local support for the bid at 63 per cent.

If Hamburg does buck the trend, it would be well worth the Movement studying the persistent, innovative, community-spirited promotional drive that will have played a big part in winning the day.

And this is where we return to those multi-coloured rain-capes.

Blue, black, red, yellow and green are, as this audience will probably have spotted, the colours of the five Olympic rings.

Sunday’s idea is for Hamburg citizens to go to the park and form a giant (highly photogenic) human Olympic rings logo.

They have been asked to dress in one or other of the five colours in order to facilitate this.

The rain-capes are, as I understand it, insurance, both against those who neglect to do so and a November downpour.

This convivial, child-friendly exercise is typical of the type of initiative being laid on by the Feuer und Flamme (“fire and flame”) marketing campaign in the run-up to the referendum.

I must admit such publicity-drives generally leave me cold.

What makes this one unusual - and, for my money, unusually appealing and, I suspect, effective – is that it is being driven not by political or even sporting authorities, but by businesses and people who want the Games to come to the city.

“The whole idea is to have it bottom-up,” Alexander Otto, the Hamburg-born, Harvard-educated shopping-centre specialist who describes himself as Feuer und Flamme’s “key fundraiser”, told me in a telephone interview.

“We try to create a lot of little local events, not just VIP events, and not just downtown.

That very night, for example, Otto was due to speak at two events in southern Hamburg.

He explains to me that the Feuer und Flamme concept – in German idiom, the phrase can take the meaning of “I’m burning for it” or “I really want it” – actually dates back to the race to be German candidate for the 2012 Olympics and Paralympics in 2003, in which Hamburg was runner-up to Leipzig.

This time around, one of the first ideas was to erect a miniature stadium in one of Otto’s company ECE’s Hamburg shopping-centres.

Passers-by who favoured the Olympic project were invited to place a miniature spectator into this stadium.

Events have been put on with the local arts community – says Otto: “It was important to get people from the cultural side involved” – while sports days at which those arriving in sports clothing gain free admission have been another feature.

Otto tells me a total of €3.2 million (£2.3 million/$3.4 million) to promote the bid has been raised, in spite of a €100,000 (£71,500/$109,000) ceiling on donations – “I didn’t want anyone to dominate,” he explains.

With the clock now ticking down to the November 29 voting deadline, Otto says there is something just about every day.

Famous German athletes from the past including high-jumper Ulrike Meyfarth, Olympic gold medallist in both 1972 and 1984, and swimmer Michael “the Albatross” Gross, have been involved.

Two fun runners are aiming to jog through all Hamburg’s 104 quarters, or “stadtteile”, before November 29.

A sports foundation, funded by a handball/hockey arena, was set up by Otto around a decade ago.

This arena was used for an Olympic roundtable discussion featuring more than 40 participants seated around a big table.

Otto emphasises that opponents of the 2024 project are invited to all discussions.

There have, he acknowledges, been protestors at some events, though opposition is generally not “vehement”.

He describes the concept of the Olympic Games coming to his city as “a bit like a childhood dream”.

But, come on, surely a major retail-related business like ECE would do very nicely thank you out of such a massive event coming to town?

“I have declared that we won’t be building any Games-related buildings,” he replies, calmly.

“I think it is important for the key ambassador not to have any economic interest.”

The referendum result is certainly not yet in the bag: asked about the media storm that has engulfed the German Football Association (DFB), Otto replies: “Of course we are not very happy about it, but it is too early to tell if it will have an effect.”

He also sounds a little uneasy about the possible impact of the current refugee crisis, suggesting it might coax people towards the view that, while the Olympics is a good idea, there are other issues that need to be dealt with.

From what I have seen of this novel, privately-funded and above all local campaign, however, it strikes me as just the way to bring around an open-minded if sceptical and perhaps somewhat apathetic population to the opportunity that the Games can represent.

Come to think of it, with a big influx of new IOC members expected next summer, doesn’t Otto seem just the sort of individual whose enthusiasm for sport, commercial expertise and level-headed multiculturalism would make a valuable addition to this most prestigious of clubs?

This has only just occurred to me, so I neglected to ask him if he had the time or the interest to contemplate such a commitment.

But if they pull it off and actually clear this testing referendum hurdle, then one way or another Lausanne should take pains to absorb the lessons in humility and campaigning acumen that the Hamburg case-study could provide.