The claim:

“It rains more in Rome than it does in London. That’s the key statistic. I can give you the official meterogical [sic] statistics. It’s officially not raining in London 94 per cent of the time.”

– London Mayor Boris Johnson, opening of Olympics Media Centre, July 16 2012.


The background:

When it came to his turn on the podium, Boris Johnson couldn’t resist but bring the weather into his spiel on the wonders of the English capital.

“You will discover a city that has twice as many bookshops as New York, and about a quarter of the murder rate, by the way,” he began. “More Michelin-starred restaurants than Paris, if I’ve got that statistic right…I think I’m getting some learned nods there, but if I’m wrong I’m more than happy to go and verify that. In Paris.”

Nobody laughed, so Mr Johnson went on: “It rains more in Rome than it does in London. That’s the key statistic.”

The audience didn’t sound convinced. So Mr Johnson got louder and started shaking his briefing notes at them, saying: “It does! Let me tell you. I can give you the official meteorogical [sic] statistics. It is officially not raining in London 94 per cent of the time.”

By now, people were laughing. “I hope that you will see what our great city has to offer,” he continued.

FactCheck doesn’t take issue with the virtues of London, but we didn’t think the weather was one of them. So we decided to investigate.

The analysis:

Let’s face it: the weather’s the main one that piques all of our interest.  We’ve been hearing for weeks now how it’s been the wettest summer since records began, to the extent that the dreaded hosepipe ban has even been lifted.

Yet the mayor claims to be in possession of statistics which suggest it’s drier in London than in Rome.

We asked the Met Office about that. They said they didn’t have a city-by-city breakdown. But certain areas are mapped out, with Greenwich, in south east London, being one of them.

From 1961 to 1990, on average per year, Greenwich was submerged in 585.8mm of rain. Rome, on the other hand, got some 813.8mm a year, on average, over the same period.

So Mr Johnson’s right – London is drier than Rome.

But the problem was that he didn’t stop there. He raced along to claim “it is officially not raining in London 94 per cent of the time”.

Again, all roads lead to the Met Office when it comes to rainfall calculations. They said that it rained for an average of 109.5 days a year from 1961 to 1990. That’s about once every three days.

Aside from the fact that that’s considerably higher than the once every 20 or so days Mr Johnson claims it rains, it’s also more than Rome’s yearly rainfall average over that period – 73.9 days a year, or one in every five days.

Where did Mr Johnson get his statistics from? We asked the London Mayor’s press office. “He might have that somewhere in his head,” came the answer from one spokeswoman.

FactCheck pointed out that Mr Johnson had said he could “give the official statistics”, so could we take him up on his offer?

Apparently not, as they never arrived.

We also did a quick check on a couple of other things the mayor raised – that there were more bookshops in London than in New York, and that there were more Michelin starred restaurants in London than in Paris.

The Booksellers’ Association told us that there were 256 bookshops in London at the end of 2011, including independents and chains. Their US equivalent didn’t have a number for total number of New York bookstores, but a quick check online revealed as many as 650, though admittedly, we didn’t phone each one individually.

At last count, there were 55 Michelin starred restaurants in London. Equivalent in Paris? 82.

And murder? Well, there were 490 murders in New York last year, according to police statistics. The Metropolitan Police say there were 117 murders across the city last year. Both cities have populations hovering just above the 8m mark.

The verdict:

FactCheck is going to have to pour cold water on Mr Johnson’s claim that it rains more in Rome than it does in London. Lots of his other claims are a washout too.

He’s right when he says Rome is drier than London, but there’s nothing to stand up his claim that it doesn’t rain in London 94 per cent of the time.

On restaurants, we foresee a trip to Paris in the offing, because he’s wrong on that one too. Likewise, it’s be worth him taking a trip to New York to visit one of the city’s many bookstores. He’d have a wider choice than in London.

He knows what he’s talking about when it comes to murder, however.

We asked the London Mayor’s office about the rainy day claims.

A spokeswoman said: “It was a joke comment made by the Mayor in answer to a couple of questions at the event. It was taken as such by all those who attended.”

She added: “However it is a fact that London is drier than Rome.”