A 500-mile-wide cloud of Saharan dust is set to blow across the UK on Wednesday, as one of the warmest Februarys on record continues.
Wednesday is forecast to rise into the teens once again, continuing an unseasonable mini-heatwave for the South West.
However, as well as warmth, the dusty air blown 2,000 miles from the Sahara will cause high levels of pollution, Devon Live reports.
Met Office forecaster Sophie Yeomans said: “Some air has come from the Sahara, with temperatures more than 10 C above average."
“Wednesday will be Britain’s worst air pollution episode for a year - since the Beast from the East, DEFRA forecasts show,” said Simon Birkett, director of campaign group Clean Air in London.
“It's a perfect storm of three factors – Saharan dust, pollution from the continent’s power stations, factories and farming fertilisers, and light winds meaning homegrown traffic pollution doesn't disperse.
The Department for Environment, Food & Rural Affairs said: “Moderate to high levels of air pollution are forecast to persist during Wednesday, with a risk of very high levels in urban centres of northern England.
“There is the potential for Saharan dust. There is a mixture of locally generated and continental sources coupled with light winds.”
DEFRA guidance for very high air pollution encourages older people, adults and children with lung problems and adults with heart problems to avoid strenuous physical activity.
People with asthma may find they need to use their reliever inhaler.
“The general population should reduce physical exertion, especially if you experience a cough or sore throat,” it said.
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