What Is Fog? Types and Formation Explained 🌫️

You may well be familiar with fog, but have you ever wondered what it is, or how it forms? <br /><br />You can find more information on different types of fog, on the Met Office website: http://www.metoffice.gov.uk/learning/fog<br /><br />Put simply, fog is very low lying cloud. Like a cloud, fog is made up of millions of tiny water droplets or ice crystals that form when air is cooled close to the Earth’s surface and water vapour within it condenses.<br /><br />These droplets are light enough to remain suspended in the air<br /><br />There are several different types of fog, each forming under different conditions.<br /><br />Radiation fog forms in situ at night under clear, cold and relatively calm conditions, when water vapour close to the cold ground condenses as it cools.<br /><br />Radiation fog can be very slow to clear during the winter months when the sun is weak.<br /><br />Advection fog forms when moist air flows over a relatively cold surface and is cooled.<br /><br />When this happens the air can no longer hold moisture and so condenses, forming fog. <br /><br />A common example of this is coastal fog where relatively warm moist air passes over the cool surface of the sea.<br /><br />Coastal fog usually occurs in the spring and summer months when conditions begin to warm up but the sea which warms more slowly, stays relatively cold<br /><br />Music: Betty Trinh - Sunday Afternoon