172 



THE CLIMATE OF ST. MARY's COUNTY 



The longest consecutive period of cold weather occurred in February, 

 1895; during that month the temperature was 32° or below on 25 days, 

 and 20° or below from the 3d to 15th, as follows: 



3d, G° ; 4th, 14° ; 5th, 5° ; 6th, — 5° ; rth, 8° ; 8th, 1° ; 9th, 5° ; 10th, 

 10° ; 11th, 9° : 12th, 10° ; 13th, 18° ; 14th, 11° ; 15th, 12°. The follow- 

 ing is the record for the cold wave of February, 1899 (temperatures 20° 

 or below) : 8th, — 1° ; 9th — 16° ; 10th, — 17° ; 11th, — 19° ; 13th, 4° ; 

 13th, 5° ; 14th, 4° ; 15th, —2°. 



These two remarkable cold waves are illustrated graphically in Fig. 11. 



Duration of tJic Crop Season. 



The date of the last killing frost in spring averages somewhat later 

 than at Solomons, the mean for eight years being April 15 ; the 

 average date of the first killing frost in autumn is October 17, 27 days 

 earlier than at Solomons. While the record for Charlotte Hall is not 

 very complete, the figures, nevertheless, indicate that the proximity of 

 the waters of the Bay lengthens the growing season, which is 6 months 

 and 2 days at Charlotte Hall, as compared with 6 months and 21 days 

 at Solomons. A light frost has occurred at Charlotte Hall as late as 

 May 26 (1899), with a minimum temperature of 36°. Tlie earliest 

 light frost was apparently that of Septeuiber 30, 1895. 



The following table gives the dates of the first and last killing frosts 

 as far as available: 



1893 

 1894 

 1895 

 1896 

 1897 

 1898 

 1899 

 1900 

 1901 

 1902 

 1903 

 1904 



First In Autumn. 

 October IT. 

 October 15. 

 October 10. 

 October 25. 

 November 13. 

 October 24. 

 October 2. 



October 17. 

 October 16. 

 October 30. 

 October 27. 



April 22. 



