sm-art

Analyses

1. Rainfall: London vs other UK place

First let’s look at within the UK.

Graph 2: Annual Average Rainfall Amount 1981-2010

Source: Met Office

OK, London area is one of the driest areas in the UK. In fact, London’s annual precipitation is just above 600mm - sounds much better than the >3,000mm areas in Scotland.

So at least it’s possible that London got its unfair share of bad weather reputation is true.

2. Rainfall: London vs other European cities

This time I’m focusing on historically important cities in Europe around 1800s, taken from this Wiki page. Well, it seems **London has below average annual rainfall among big European cities. **In fact, Milan, Istanbul, Rome, Lisbon, Paris and even Cordoba all have more rainfall than London.

Yes, I know, rainfall in mm alone doesn’t say much. So let’s look at number of rainy days in these cities. This time we’re onto something. London is 6/21 in terms of precipitation days, although it’s still behind Lisbon and Paris. Italy and Spain (of course) have the least rainy days.

Graph 3: Annual Rainfall and Number of Annual Rainy Days by City

Data Source: Wikipedia city pages climate sections; collated here

Then I also expanded this list to include other global cities such as New York, Shanghai, Tel Aviv etc, and London is still pretty much at the middle of the pack.

Graph 4: Annual Rainfall and Number of Annual Rainy Days by City (Extended)

Data Source:_Wikipedia city pages climate sections

So I guess it isn’t really true that London is much worse than other European cities in terms of rainfall or number of rainy days.

3. Sunshine, sunshine, sunshine

On the Wiki page of Climate of London, in the intro section:

While the city annually has modest precipitation, annually averaging less than cities like Rome, New York City, or Shanghai, unlike those cities, London has many long periods (weeks sometimes) of overcast skies and frequent light mist-type precipitation, which may account for the rainy image of the city.

However there is no source listed on this.

So it brought me to my most important piece of investigation (as it later transpired) - what about sunshine? Is it so that it’s just always gloomy in London, although it doesn’t actually rain much?

So I did the same analysis, but using yearly hours of sunshine as a metric. And bingo - among the 360 cities globally investigated, London is ranked 331 (bottom 8th percentile) in terms of sunshine hours. Notable cities even cloudier than London are Copenhagen, Guangzhou, Hanoi, Warsaw, Zurich, Brussels, Dublin, Edinburgh, Bergen etc.

Graph 5: Annual Hours of Sunshine, Colored by Decile

Data Source: Wiki page

So yes, based on this data, there’s some truth to the stereotype.

4. What about sunshine hours across the UK?

Important question left: but is London really bad by UK standard as well? We saw earlier that London is among the driest places in the UK, but what about sunshine duration?

For that, I used the Met Office Station Historical Data and selected a few stations with sunshine data across the UK.

And it seems London is pretty much in the low-middle (not much variance overall). Remember that London is among the driest, however,** it is more cloudy than rainy**, by UK standard.

Graph 6: Annual Hours of Sunshine, Avg 2015-2019

Data Source: Met Office

I also had a quick look at the time series (the data goes back quite a bit), but it seems to be pretty consistent and I can’t find any major changes.

Conclusion

Yes, there is some truth to the stereotype. Although I feel London’s weather is pretty fine (not too hot, not too cold, always mild, and I never need an umbrella - it’s either drizzle or you can wait it out), it seems its bad reputation mainly stems from its gloominess/cloudiness.

That being said, I still feel something not captured in this is what type of cloudiness it is. There is a major difference between a straight two weeks of absolutely no sunshine + straight two weeks of sunshine, vs half of a day of sunshine everyday. And I feel London is more of the latter. It’s not guaranteed, but sunny spells are quite common.

Okay, but what about Hypothesis 5? I don’t know - ask your British friends. My hypothesis is that the hypothesis is true, of course.

Bonus

With the data I have, it’s very tempting to do scatters (in the vein of the good old 2x2). Where do you want to live? Lots of sun and lots of rain? Lots of sun and no rain? Or maybe lots of rain and no sun? Or maybe rather you don’t care - then I have no idea why you’ve read till this point.

Graph 7: Annual Hours of Sunshine vs Rainfall (mm)