The UK has been warned of high pollution levels this week, particularly today Friday 10 April as the hot weather takes air pollution to level 10- the highest level.
The warm and still conditions are expected to have an effect on the air and so people are being advised to avoid strenuous activity.
Asthmatics in particular are at high risk of experiencing breathing difficulties thanks to a combination of traffic fumes, dust from the Sahara and pollution from the continent.
The pollution is expected to disappear by the weekend, however, when Atlantic winds disperse polluted air by Saturday.
Signs of air pollution affecting you include a dry throat or tickly cough and sore eyes.