Blood rain is set to fall on the UK tomorrow (Picture: Rex/Shutterstock)

Authorities have sent out a warning as a cloud of smog is set to hit the UK.

The Department For Food, Agriculture And Rural Affairs (Defra) has issued a level-8 red alert for air pollution as a cloud of toxic dust and ‘blood rain’ is set to engulf areas in south and central England.

South-eastern areas are expected to the worst hit tomorrow (Thursday December 17) as the smog blows in from the Sahara.

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Defra advise: ‘Adults and children with lung problems, and adults with heart problems, should reduce strenuous physical exertion, particularly outdoors, and particularly if they experience symptoms.



‘People with asthma may find they need to use their reliever inhaler more often. Older people should also reduce physical exertion.’

Adding: ‘Anyone experiencing discomfort such as sore eyes, cough or sore throat should consider reducing activity, particularly outdoors.’

What is blood rain? Blood rain is the term used for water carrying sand from the desert. It has a reddish colour when it falls and the thin layer of dust it leaves on the ground when it dries is also a red-brown. In the UK, storms in the Sahara desert are usually responsible for stirring up the dust that reaches our shores. Incidents of blood rain in Britain are usually short-lived. In other parts of the world, they can be more dramatic. The blood rain that fell on parts of India for two months in 2011 was so thick that it stained clothes.

A level-8 red alert is in the ‘high’ air pollution band and the director of advice at Asthma UK has warned the toxic dust cloud, paired with the changing weather create the ‘perfect storm’ for people with respiratory conditions and implores people not to underestimate the warning.

Asthma UK’s Andrew Proctor said: ‘People with asthma need to take extra care.

‘We are facing a perfect storm of asthma triggers, with air pollution and weather changes increasing the risk of potentially fatal asthma attacks for millions of people with the condition.

‘Two thirds of people with asthma find that air pollution makes their asthma worse, and even more tell us that changes in the winter weather can trigger asthma attacks.’

Experts have warned to keep outdoors physical exertion to a minimum (Picture: Rex)

He also added that people with asthma should ‘check forecasts and carry your reliever inhaler with you at all times.’

Thankfully, air pollution levels will fall back to low levels on Friday and for most of the weekend.

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