Monthly Summary 



September, 1929 



Normal 



Extremes 



Barometer 



(Readings reduced to sea level) 



Maximum 30.61, 22nd 30.45 



Minimum 29.74, 10th 29.59 



Mean semi-daily 30.107 30.068 



Range 87 0.86 



Air Temperature 



Highest 97.0,4th' 87.4 



Lowest 33.0, 23rd, 24th 32.8 



Mean 63.1 I 61.6 



Monthly range 64.0 54.6 



Highest mean daily 81.5, 4th 



Lowest mean daily 48.0,19th 



Mean maximum 75.8 



Mean minimum 50.6 



Greatest daily range 48.0, 24th 



Least daily range 3.0, 9th 



Precipitation 



Precipitation. In inches 3.62 3.79 



Maximum precipitation in 24 hrs. 1.74, 



7th, 8th [ 



Number of days on which .01 or } 



more inches of rain fell 8 9 



Wind (miles) I 



Total movement 3184 



Greatest daily movement .... 266, 11th, 



Least daily movement 34, 24th 



Mean hourly velocity 4.4 



Maximum velocity for 5 min 26,11th 



(corrected to conform to 3 cup anemometer) 

 Wind (direction) 



Prevailing direction w 



North, days 4 



Northeast, days 2 



East, days 1 



Southeast, days 2 



South, days 8 



Southwest, days 2 



West, days 4 



Northwest, days 7 



Weather 



Mean relative humidity, per cent 72.4 go.o 



Mean cloudiness, per cent 58 43^7 



Number of clear days 12 '9 



Number of fair days 9 n 



Number of cloudy days 9 10 



Number of hours bright sunshine 175.3 202.5 

 Percent of possible hours of bright 



sunshine 47.0 54 



Frosts 19th, 20th, 21st, 22nd, 23rd, 24th 



First Frost 19th 19 



Thunder and lightning 8th, 29th 



3252 



4.5 

 22 



30.65, 1924 

 29.32, 1900 



1.20, 1924; 0.57, 1910 



97.0, 1895 

 24.5, 1914 



8.74, 1907; 0.52, 1914 



15, 1918; 3, 1903 

 4686, 1896; 1414, 1894 



39, 1915 



89, 1927 ; 70.7, 1892 



65, 1889; 27, 1908, 1914 



18, 1891; 2, 1907, 1928 



19, 1908; 3, 1889 



19, '89, '07, 4, '08, '16 



255, 1916; 110,1907 



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



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

 month. The second and third columns give the averages and e.xtremes observed from iSSg 

 to 192S for the same month of the year. 



