MONTHLY SUMMARY 



August 1939 



Normal 



Extremes 



Barometer, in inches 



(Readings reduced to sea level) 



Maximum 30.30, 12th 



Minimum 29.73, 9th 



Mean semi-daily 29.989 



Range 57 



Air Temperature, in degrees F. 



Highest 89, 15th, 22nd 



Lowest 54, 6th 



Mean 73.5 



Range 35 



Highest mean daily.. 81, 21st 



Lowest mean daily 64.5, 29th 



Mean maximum 84.2 



Mean minimum 62.7 



Greatest daily range 34, 6th 



Least daily range 7, 31st 



Precipitation, in inches 



Precipitation 3.89 



Snow 



Max. precipitation in 24 hrs. . 2 23, 3rd, 4th 

 Number of days with .01 or more 



Wind, in miles 



Total movement 3335 



Greatest daily movement 192, 30th 



Least daily movement 50. 23rd 



Mean hourly velocity 4.5 



Maximum velocity 28, 16th 



Wind, direction 



Prevailing direction SW 



North, days 4 



Northeast, days 1 



East, days 1 



Southeast, days 4 



South, days 7 



Southwest, days 6 



West , days 2 



Northwest, days 6 



Weather 



Mean relative humidity, percent 72.9 



Mean cloudiness, percent 57 



Number of clear days 21 



Number of fair days 3 



Number of cloudy days 7 



Number hours bright sunshine 287 



Percent of possible hours of bright 



sunshine 66.9 



Thunder and lightning. . .3, 4, 9, 13, 16, 17 



18, 21, 25 



30.32 



29.61 



30.00 



.71 



91.6 

 43.4 

 68.6 

 48.1 



4 08 



11 

 3127 



4 2 



22.7 



SW 



70 2 



49.7 



9 



13 



9 



237 



55.2 



30.50, 19.34 

 28.87, 1930 



100, 1918 

 37, 1894, 1908 



8 40, 1928; .31, 1894 



16, 1892, 1933; 4, 1899 

 4,271, 1910; 1,920, 1894 



35, 1915 



67, KOI; 27, K23 



17, 1921,1936;0, 1915, 1929 



25, 1912;5, '93, '33, '36 



18, 1901, '28; 2, '10, '23 



317, 1921; 152, 1915, 1929 



Note — The first column in the above summary gives observations made during the 

 month. The second column gives the averages based on observations made from 

 1889 to 1938, except that humidity records are based on observations made from 

 1929 to 1938. The third column gives extremes observed from 1889 to 1938. 



