Weather Systems

3. ________ fronts occur when a warm air mass moves into an area of cold air.
8. The zone of low pressure where the trade winds meet is called the inter-tropical __________ zone.
9. The area of calm at the center of a hurricane.
10. Tropical waves develop from atmospheric disturbances as far away as this continent.
11. Cold fronts often result in _________.
13. A tropical _________ is a cyclonic storm with winds speeds of at least 39 miles per hour but less than 74 miles per hour.
16. There are five ________ of hurricanes.
19. When warm air meets cold air, the warm air is forced to _________.

1. A powerful cyclonic storm with maximum sustained winds of at least 74 miles per hour.
2. Hurricanes are known for powerful winds and heavy _________.
4. A tropical wave can develop into a tropical ___________.
5. Hurricanes generally move toward the _________.
6. Anticyclones are associated with _________ weather.
7. Tropical waves are troughs of low _________ which occur in tropical areas.
12. _______ fronts occur when a cold air mass moves into an area of warm air.
14. The most powerful hurricanes are category ________ .
15. _______ seas are the source of a hurricane's energy.
17. This is a high pressure system within which air is descending.
18. The strongest winds in a hurricane occur in the __________.