A STUDY OF WEATHER MAPS 



255 



the data from the table of weather reports for March 3, 1904. Follow 

 the same order and complete the map in the same manner. Compare 

 the two maps. Note the new position of the LOW. Draw a light 

 broken line along the path its center seems to have followed. Meas- 

 ure the distance it has traveled in 24 hours. Draw a similar line for 

 the center of the HIGH that is following. How far has it traveled? 

 Make a table showing the changes in temperature, the shift of the 

 wind, and the amount of rain or melted snow in the last 24 hours, at 

 each place on the map. Considering the facts already studied, ex- 

 plain what caused the changes in temperature and wind that occurred 

 at the following places: Bismarck, Cleveland, Cincinnati, Dubuque, 

 Green Bay, Hatteras, Kansas City, Lynchburg, Memphis, Moor- 

 head, Pueblo, Rapid City, Shreveport, Valentine. 



VII. A STUDY OF WEATHER MAPS 



280. A Further Study of Weather Maps. After preparing 

 the foregoing exercises, the reader will find it much easier to 



FIG. 179. Weather map of 8 A. M., December 4, 1906. Solid lines show 

 pressure. Broken lines are isotherms. Single shading shows area of cloudy 

 sky. Double shading, area where rain or snow has fallen in last 24 hours. 

 Cirrus clouds usually extend in advance of cloud area on east and northeast, 

 but not enough to cover the sky. 



see all there is on a weather map. The following completed 

 maps show the progress of a typical storm across the United 



