3. 1. What are the lines of equal air pressure called? 3.Draw the symbols for: i) a cold front ii) a warm front 4. What happens at cold and warm fronts? A Synoptic Chart 2. How can we tell this chart shows a depression? 5. How can we tell from the isobars that it is moderately windy?

4. The warm front is called the leading front as it is first to pass over places in the UK. The warm front marks where a mass of warm meets a mass of cold air. At this front warm air rises over the mass of cold air. As the air rises the air cools, condenses, forms clouds and produces rain. The passing of the warm front

5. As the warm front passes over the rain will stop and it will become drier. Places in the UK will now be in the warm air sector between the fronts and temperatures should be warmer as a result. The cold front will be next to pass over and this will again bring rain.

6. At the cold front the warm air is forced to rise above the cold air mass coming along. Again warm rising air cools, condenses, forms clouds and will give rain. Passing of the cold front

7. In the northern hemisphere winds in a depression blow anticlockwise around the depression and (roughly) parallel the isobars

8. 6. What causes it to rain along the cold front? 7. Why does it become warmer after the warm front passes over a place? 8. Describe what happens to the next to the weather as the cold front moves in. 9. In what direction do winds blow around a depression in the UK?

9. G 10. Describe the weather in Glasgow (G). 11. Describe and explain how the weather in Glasgow will change later in the day. A point to remember is that depressions move across the UK in a generally West to East Direction.