Synoptic charts display the observation data in a compact form, using a standard set of symbols to represent the various components that make up the weather, such as prevailing weather conditions, cloudiness and wind. An international station modelfor a synoptic weather chart Meteorologists analyse the synoptic charts to study how the weather patterns are likely to change in the short term. In tropical regions, synoptic charts are analysed by drawing streamlines to give a clearer picture of the wind flow. In the middle latitudes, synoptic charts with isobars , or lines joining points of equal air pressure, are more useful than streamlines. This is because the weather in the middle latitudes is controlled by a sequence of high and low pressure frontal systems.
Frontal systems arise from the meeting of two air masses of different temperature and moisture.