How It Works

Are Britain’s roads really going to melt this summer?

The British are not well equipped to deal with the heat and it turns out neither are our roads

You know the Met Office isn’t overreacting when announcing an amber alert (the second most severe alert issued by the agency) if the roads start to melt, and that’s exactly what is predicted to happen over the next couple of days.

So why are our roads suffering when millions of roads around the world are holding up just fine? It’s because we’re not prepared for many variations in our weather. Just like the British people, British roads also don’t like hot weather (or cold weather). Much like us, our roads are much more comfortable with high rainfall rather than temperatures soaring beyond 32C.

Tarmac starts to melt at around 50C so it sounds like it shouldn’t be a problem as the temperatures we are experiencing are mostly in the mid-30C range. But a combination of factors makes our roads much hotter than the air; predominantly that the temperature in direct sunlight is much hotter and so ground temperature has started to rocket. It also doesn’t help that tarmac is a dark material that absorbs heat. There are some materials that do withstand heat very well and these are used in other countries, but here in the UK this blistering heat only happens a few days every couple of decades. The high temperatures are expected to cause our roads to become slick and soft and the top layer between 3 – 5cm thick starts to melt and the effects will be more noticeable on high traffic roads.

It’s not pleasant and may result in road disruption as parts get closed and gritting lorries take to the motorways to grit over the softening surfaces, but is there much of a better excuse than to stay home and eat an ice cream more than ‘the roads have melted’?


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Other articles you may like:

Britain’s scorching heatwave: why is it here, and when will it leave us alone?
If body temperature is 37°C, why do we feel hotter when it’s 30°C outside?
Heatwaves explained: The causes and effects of hot weather