Weather Producers

1. Weather Producers www.assignmentpoint.com

2. Introduction • There is a shift in weather during the changes of the seasons that is related to: • Movement of air masses • Leading fronts of air masses • high and low pressure areas www.assignmentpoint.com

3. Air Masses • Polar air mass • An air mass that moves from a cold region • Tropical Air Mass • An air mass that moves from a warm region • Continental Air Mass • Moves in from a land mass • Maritime Air Mass • Moves in from over an ocean www.assignmentpoint.com

4. Major types of air masses • Continental Polar • Cold • Dry • Maritime Polar • Cold • Moist www.assignmentpoint.com

5. Continental Tropical • Warm • Dry • Maritime tropical • Warm • Moist www.assignmentpoint.com

6. The general movement of the four main types of air masses that influence the weather over the contiguous United States. The tropical air masses visit most often in the summer, and the polar air masses visit most often during the winter. During other times, the polar and tropical air masses battle back and forth over the land. www.assignmentpoint.com

7. This satellite photograph shows the result of a polar air mass moving southeast over the southern United States. Clouds form over the warmer waters of the Gulf of Mexico and the Atlantic Ocean, showing the state of atmospheric instability from the temperature differences. www.assignmentpoint.com

8. Air mass weather • When the weather in an area is under the influence of an air mass. www.assignmentpoint.com

9. Weather Fronts • Front • A boundary between two different air masses • Cold Front • When a cold air mass moves into a warmer area, displacing the warm air mass • Provides lift to adiabatically cool the warm air, resulting in towering cumulus and thunderclouds. www.assignmentpoint.com

10. (A)A cold air mass is similar to a huge, flattened bubble of cold air that moves across the land. The front is the boundary between two air masses, a narrow transition zone of mixing. (B) A front is represented by a line on a weather map, which shows the location of the front at ground level. www.assignmentpoint.com

11. An idealized cold front, showing the types of clouds that might occur when an unstable cold air mass moves through unstable warm air. Stable air would result in more stratus clouds rather than cumulus clouds. www.assignmentpoint.com

12. Warm Front • When a warm air mass moves into an area, displacing the cold air mass • A gently sloping front as the Warm air moves over top of the cooler air. • Stationary Front • When the edge of a front ceases to advance www.assignmentpoint.com

13. An idealized warm front, showing a warm air mass overriding and pushing cold air in front of it. Notice that the overriding warm air produces a predictable sequence of clouds far in advance of the moving front. www.assignmentpoint.com

14. Waves and Cyclones • Occluded Front • One that has been lifted completely off the ground • Has s low pressure center and cyclonic activity • Cyclone • a low pressure area with winds moving into the low pressure area and being forced upward. • Friction and the Coriolis effect cause the air to move to the right of the direction of movement. • Anticyclone • A high pressure center www.assignmentpoint.com

15. The development of a low-pressure center, or cyclonic storm, along a stationary front as seen from above. (A) A stationary front with cold air on the north side and warm air on the south side. www.assignmentpoint.com

16. (B) A wave develops, producing a warm front moving northward on the right side and a cold front moving southward on the left side. www.assignmentpoint.com

17. (C) The cold front lifts the warm front off the surface at the apex, forming a low-pressure center. www.assignmentpoint.com

18. (D) When the warm front is completely lifted off the surface, an occluded front is formed. www.assignmentpoint.com

19. (E) The cyclonic storm is now a fully developed low-pressure center. www.assignmentpoint.com