254 



THE CLIMATE OF CECIL COUNTY 



average values of 56.3°. Such contrasts in seasonal temperatures 

 increase in magnitude in the temperate regions as the distance from 

 the coast increases and reach their greatest development in northern- 

 central regions of the large continental masses. The month exhibit- 

 ing the greatest amount of change in the average temperature from 

 year to year is February, with a maximum of 38.2° in 1867 and a 

 minimum of 23.1° in 1875, a difference of 15.1°. The least change- 

 able month is June, having varied but 4° within the period of eleven 

 years. The variability of temperature during the winter months is 

 nearly three times as great as during the summer months. The 

 monthly and annual mean temperatures for the entire period from 

 1865 to 1875 are shown in Table I on the preceding page. 



EXTREMES OF TEMPERATURE. 



In selecting a suitable locality for residence or for conducting 

 profitable farming operations it is of vital importance to know the 

 extreme limits of variability in temperature to which the region is 

 subjected, as well as the time and manner of occurrence of changes. 

 An intimate knowledge of the extreme daily or monthly range, of 

 the probability of occasional sudden changes of great magnitude, of 

 the occurrence of frost at critical periods of plant growth, is of the 

 utmost importance. Average values are not a sufficient guide. The 

 difference between the highest and lowest temperatures of the month 

 and year under extreme conditions and under average conditions is 

 shown by the following figures: 



Difference with ex 

 treme conditions. , 



Difference with av- } 

 erage conditions. . . ^ 





ft 





ft 

 < 



>> 



OS 



s 



3 



1-5 



in 



6C 

 < 



ft 



© 



Oct. 

 Nov. 



6 

 © 



72 



80 



80 



66 



54 



42 



42 



40 



51 



57 62 



74 



53.0 



54.0 



52.6 



45.7 



43.2 



34.4 



31.0 



31.7 



42.1 



43.945.6 



1 



49.4 



110 

 93.0 



From this table it appears that the annual extremes of temperature 

 may vary by 110°, that the monthly extremes in February and 

 March may vary by 80°, while the summer months exhibit a varia- 

 bility of about one-half that of the winter months. July is the month 



