TEMPERATURE CONDITIONS. 



263 



The absolute maximum temperature observed was 38. 8° C. (102° F ) 

 as compared with 39.4° C. (103° F.) at Cape Henry, 38.8° C. (102° F ) 

 at Norfolk, and 39.4° C. (103° F.) at Wilmington. 



The absolute minimum temperature observed w as 13. 3° C. (8. 0° F ) 



ascomparedwith — 15.0° C. (5.0° F.) at Cape Henry, — 1G.G° C (2 0^ 

 F.) at Norfolk, and — 12.8° C. (9.0° F.) at AVilmington. 



The absolute monthly maxima and minima are as follows: 



The average date of the latest killing frost in spring is February 

 25, as compared with March 19 at Cape Henry, March 2G at Norfolk, 

 and March 15 at Wilmington. The latest recorded was April 5, as 

 compared with April 19 at Cape Henry, April 26 at Norfolk, and April 

 20 at Wilmington. 



The average date of earliest killing frost in autumn is December 13, 

 as compared with November 14 at Norfolk and Cape Henry and 

 November 12 at Wilmington. The earliest killing frost recorded was 

 on November 12, as compared with November 14 at Cape Henry, Octo- 

 ber 15 at Norfolk, and October 13 at Wilmington. 



From the above data the temperature may be characterized as fol- 

 lows: Warm, but not excessive, with a considerable sum total of 

 effective temperatures during the growing season, and usually mild 

 temperatures during the very brief dormant period. The normal 

 temperature is at least (j.5° C. above freezing point during every 

 month of the year. The normal amount of daily variation of tem- 

 perature is, according to the season, from 5° to 7° C, a relatively 

 very small range. The period between the average dates of the 

 earliest killing frost in autumn and of the latest in spring, which may 

 be taken as very roughly coinciding Avith the dormant period of most 

 of the vegetation, covers only seventy-four days. 



