Monthly Summary 



•September 1987 



Normal 



Barometer 



(Readings reduced to sea level) 



Maximum 30.55,30th 



Minimum 29.52, 11th 



Mean semi-daily 30.065 



Range 1.03 



Air Temperature 



Highest 92, 3rd 



Lowest 36, 30th 



Mean 60.0 



Monthly range 56 



Highest mean daily 81, 3rd 



Lowest mean daily 51, 20th 



Mean maximum 71.8 



Mean minimum 48.3 



Greatest daily range 37, 24th 



Least daily range 6, 28th 



Precipitation 



Precipitation. In inches 3.24 



Snow, in inches 



Maximum precipitation in 24 hrs. 



1.12, 13th 

 Number of days on which .01 or more 



inches of precipitation fell ... 10 



Wind (miles) 



Total movement 2,908 



Greatest daily movement 244, 20th 



Least daily movement 40, 1st 



Mean hourly velocity 4.0 



Maximum velocity, 5 min., .... 28, 20th 



Wind (direction) 



Prevailing direction wsw 



North, days 2 



Northeast, days 1 



East, days 



Southeast, days 5 



South, days 5 



Southwest, days 5 



West, days 4 



Northwest, days 8 



Weather 



Mean relative humidity, per cent. . 74.5 



Mean cloudiness, per cent 44.5 



Number of clear days 13 



Number of fair days ... 10 



Number of cloudy days 7 



Number of hours bright sunshine . . 219 

 Percent of possible hours of bright 



sunshine 58.9 



Thunder and lightning 2nd, 3rd, 4th 

 First Frost 



30.45 



29.59 



30.068 



.86 



87.4 

 32.8 

 61.6 

 54.6 



E.xtremes 



3.79 



9 

 3,252 



4.5 

 22 



73.6 



48.7 



9 



11 



10 



202.5 



54.4 



19th 



30.65, 1924 

 29.32, 1900 



1.20, 1904; 0.57, 1910 



97.0, 1895, 1929 

 2.45, 1914 



12.34, 1933; 0.52, 1914 



15, 1918; 3, 1903 

 4,686, 1896; 1,414, 1894 



39, 1915, 1934 



70.0, 1934; 27, 1908, 1914 



19, 1932; 2, 1907, 1928 



19, 1908; 3, 1889 



20, 1934; 4, '08, '16 



255, 1916; 106, 1934 



Aug. 22, '94, '95; Oct. 13, '09 



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

 month. The second column trives the averages based on observations made from 1889 

 to 19'28. except that humidit.v records are based on observations made from \'.)2'.> to 1936 

 The third column gives extremes observed from 1889 to 1936 



