Synoptic charts and weather

A synoptic chart is a more detailed weather map which shows what type of weather system is moving over Britain.

Low and high pressure

The main weather element shown on a synoptic chart is air pressure.

Isobar lines which join up areas of equal air pressure are drawn on these maps. The pattern these lines make shows areas of low or high pressure.

Charts and symbols

Be sure to examine the information on the chart carefully. In the example below the date tells you the likely weather conditions of a high pressure system.

Synoptic chart for 14 November 2010

Synoptic chart for 14th November 2010 describing weather conditions

Synoptic charts often have weather circles shown on them.