Figures 1—4 are weather maps for a 24-hour period. The maps show the position of pressure systems and fronts in the United States every 12 hours.
Examine the maps and think about what is occurring.
Then answer the following questions.
1. Briefly describe the movement of the high and low pressure systems shown on the maps.
2. Why do you think the cold front in Figure 1 developed?
3. What conditions were necessary for the development of the warm front in Figure 3?
4. What may be happening to the cold air mass as it moves southward from the Great Plains?
5. Explain what is happening to air along the cold front.