MONTHLY SUMMARY 



September, 1942 



Barometer, in inches 



(Readings reduced to sea level) 



Maximum „ 30.56, 29th 



Minimum 29.64, 27th 



Mean semi-daily 30.059 



Range 0.81 



Air Temperature, in degrees F. 



H i gliest 90, 2nd 



Lowest 28, 30th 



Mean 62.7 



Range 62 



Highest mean daily 77.5, 16th 



Lowest mean daily 43.0, 29th 



Mean maximum 74.4 



Mean minimum 5 1 .0 



rireatest daily range _ 1^7. 30th 



Least daily range „ 5, 11th 



Precipitation, in inches 



Precipitation 3.94 



Maximum precipitation in 24 hrs 1.69, 27th 



Snow „ 



Number of days with .01 or more 11 



Wind, in miles 



Total movement 2707 



Greatest daily movement 251, 28th 



Least daily movement 31, 17th 



Mean velocity 3.8 



Maximum velocity 28, 28th 



Wind, direction 



Prevailing direction „ SW 



North, days „ 2 



Northeast, days 



East, days 



Southeast, days 5 



South, days 6 



Southwest, days 5 



West, days 5 



Northwest, days 7 



Weather 



Mean relative humidity, percent 77.8 



Mean cloudiness, percent _ 53 



Number of clear days 16 



Number of fair days „ 5 



Number of cloudy days 9 



Number hours bright sunshine 224 



Percent of possible hours of bright 



sunshine 60.1 



Thunder and lightning lOth, 15th, 16th, 18th 



First frost Sept. 29 



Normal 



30.45 

 29.57 

 30.06 



87.7 



61.7 



54.5 



4.26 



10 

 3271 



4.5 

 ^5.9 



WSW 



72,.6 



49.9 



10 



10 



10 



201 



54.9 



Sept. 21 



Extremes 



30.65, 1924 

 28.41, 1938 



1.99, 1938; .57, 1910 



97. 1895, 1929 

 24.5, 1914 



14.55, 1938: .52, 1914 



16, 1933; 3, 1903 



4,686, 1896; 1,414, 1894 



80, 1938 



70, 1934; 17, 1908, 1914 



19, 1932; 2, 1907, 1928 



19, 1908; 3. 1889 



20. 1934; 3, 1941 

 255, 1916; 106, 1934 



Aug.22, "94, •95;Oct. 13, '09 



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 1941. 



