Isobars are lines on a weather map joining together places of equal atmospheric pressure. On the map the isobar marked 1004 represents an area of high pressure, while the isobar marked 976 ...

An alarming weather map has shown exactly when Storm Eowyn will hit the UK with 90mph winds, rain and show all on the cards.

On the map the isobar marked 1004 represents an area of high pressure, while the isobar marked 976 represents an area of low pressure. Not only do isobars tell us whether there is high or low ...