Spotting features on a weather map

How are you getting along with the Week so far?

In this and the next Step we’ve provided two different exercises to help you test what you’ve just learnt about depressions.

In this first exercise, your task is to match up the words and pictures listed below, with the numbers on the weather map (Figure 1). Should you wish to, we’ve provided this activity on a PDF which you can print.

• Remember that we name winds by the direction they are blowing from
• The centres of low and high pressure areas are marked with a cross and the value of the pressure in the centre
• The wind follows the isobars (lines of constant pressure) and blows around a depression in an anticlockwise direction
• You can use the same number for more than one answer
• There may be more than one correct answer

Please note: The map projection is slightly odd – North is where the lines of longitude converge, in the top left corner. The lines of latitude are the east-west axis. This projection is used for UK weather maps so that as much as possible of the relevant area around the UK can be seen.

Figure 1: © Crown Copyright, Met Office

Figure 2: Cloud pictures © RMetS

There are some additional features on the weather map (Figure 1) that we haven’t talked about. For example, the black lines running down the west coast of Scotland and off the South West corner of Ireland mark the position of a trough. A trough is an elongated area of relatively low surface pressure. The troughs marked on weather charts may also represent an area of low atmospheric thickness (thickness trough), or a perturbation in the upper troposphere (upper trough). All are associated with increasing cloud and the risk of rainfall.

Another feature which is sometimes shown is a cold or warm front where the triangles or semi-circles on the front have not been filled in – this is a front which is only found higher up in the atmosphere.

The answers will be provided in Step 1.17.