MONTHLY SUMMARY 



July. 19.S8 



Normal 



Extremes 



Barometer 



(Readings reduced to sea level) 



Maximum 30.17, 31st 



Minimum 29.70, 14th 



Mean semi-daily 29.982 



Range 47 



Air Temperature 



Highest 88, 31st 



Lowest 47, 3rd 



Mean 71.7 



Rar-ge 41 



Highest mean daily 78, 26th 



Lowest mean daily 60, 4th 



Mean maximum 80.9 



Mean minimum 62.4 



Greatest daily range 36, 5th 



Least daily range 3, 19th 



Precipitation 



Precipitation. In inches 7.45 



Snow, in inches 



Maximum precipitation in 24 hrs. 



2.07, 18th 

 Number of days on which .01 or more 

 inches of precipitation fell 13 



Wind (miles) 



Total movement 3502 



Greatest daily movement 178,22nd 



Least daily movement 41, 19th 



Mean hourly velocity 4.7 



Maximum velocity, 5 min., 28, 11th 



Wind (direction) 

 Prevailing direction ssw 



North, days 

 Northeast, days . 



East, days 



Southeast, days . 



South, days 



Southwest, days 



West, days 



Northwest, days 7 



Weather 



Mean relative humidity, per cent. . 71.8 



Mean cloudiness, per cent 55 



Number of clear days 12 



Number of fair days 9 



Number of cloudy days 10 



Number of hours bright sunshine . . 248 

 Percent of possible hours of bright 



sunshine 53.7 



Thunder and lightning 9, 11, 12, 18, 21, 29 



30.28 



29.60 



29.972 



.68 



93.9 

 45.5 

 70.6 



48.4 



4.33 



11 

 3,485 



4.6 



24 



68.0 



50.1 



9 



14 



8 



267.0 



57.8 



30.59, 1892 

 29.27, 1932 



0.97, 1892; 0.51,1895, 1899 



104.0, 1911 

 40.0,1890, 1898 



14.51, 1897; 0.70, 1929 



20, 1915; 4, 1924 

 5,097, 1909; 1,109, 1894 



44, 1936 



69, 1914; 31, 1924 



22, 1923; 0, 1915 



24, '09, '21; 5, '89,'23, '28, '36 



18, 1839; 0,1910 



371,1910; 182,1889 



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

 month. The second column erives the averages based on observations made from 18h9 

 to 1928, except that humidity records are based on observations made from 1929 to 19.S7. 

 The third column gives extremes observed from 1889 to 1937 



