1. Air Masses How do you think these air masses effect our weather?

2. AIR MASSES AIR MASS - a huge body of air that has similar temperature, humidity, and air pressure throughout.

3. Air Masses Tropical air mass - warm, low pressure air mass. Polar air mass - cold, high pressure air mass.

4. Air Masses Maritime air masses form over oceans. The air is humid. Continental air masses form over land. The air is dry.

5. Air Masses Now put the two words together! Tropical Polar Continental Maritime

6. Air Masses Tropical Maritime In summer it brings hot, humid weather. In winter it can bring heavy rain or snow.

7. Air Masses Maritime It brings fog, rain, & cool temperatures. Polar

8. Air Masses It brings hot, dry weather. Continental Tropical

9. Air Masses It brings cool or cold air. Continental Polar

10. Air Masses Label your map!

11. Weather Fronts A ir masses are moved from one area to another by wind. Front - the area where the two air masses meet.

12. http://www.classzone.com/books/earth_science/terc/content/visualizations/es2002/es2002p age01.cfm?chapter_no=visualization Cold Front - when a cold air mass is moving rapidly pushes a warm air mass out of the way. The warm air rises, thunderstorms occur. After the front passes, cool & dry air moves in.

13. COLD FRONT

14. Warm Front - A fast moving warm air mass collides with a cold air mass. The less dense warm air rises. If the air is humid, it rains. If the air is dry, scattered clouds form. http://www.classzone.com/books/earth_science/terc/content/visualizations/es2002/es2002 page01.cfm?chapter_no=visualization

15. WARM FRONT

16. Other Fronts Stationary Front - When air masses meet, but neither one can move the other. Rain, snow, fog, or clouds can form. It could rain for many days.

17. STATIONARY FRONT

18. Occluded Front - a warm air mass is caught between two cooler air masses. The warm air rises and the 2 cooler air masses meet.

19. Occluded Front The air becomes cooler on the ground. The rising warm air condenses, & the weather may turn rainy.

20. OCCLUDED FRONT

21. High and Low Pressure High Pressure - signal of fair weather. The wind spins in a clockwise direction. Low Pressure - signal of rainy weather. The winds spin in a counterclockwise direction.

22. Predicting the Weather Instruments anemometer - wind vane - thermometer- psychrometer- barometer- rain gauge-

23. How do you predict the weather? ·weather station ·satellite images ·radar images

24. Before we are ready to predict the weather, we have to learn a couple things! ·weather map symbols ·calculating relative humidity http://library.thinkquest.org/5818/maps.ht ml