The worst smog of the year is set to hit the capital this week following a Saharan storm.
The Met office have issued their highest 10 out of 10 level of air pollution warning for tomorrow, following strong winds that have deposited sand from the Sahara across Southern England.
Levels in Croydon have already reached eight out of 10, and although not deadly, those with lung and heart conditions have been advised to avoid strenuous exercise outside.
Many were made aware of the storm this morning when motorists woke up to a thin layer of red dust on their cars, which had been carried west by the southerly winds from North Africa
Once picked up by the winds, the dust can reach high altitudes and cover distances of thousands of kilometers worldwide.
Paul Hutcheon, Met Office representative said: “We usually see this happen several times a year when big dust storms in the Sahara coincide with southerly winds to bring that dust here. More dust rain is possible during showers expected later this week.”