Monthly Summary 



April, 193H 



Normal 



Extremes 



Barometer 



(Readings reduced tn sea level) 



Maximum 30.50, 7th, 8th 



Minimum 29.10, 9th 



Mean semi-daily 30.050 



Range 1.40 



Air Temperature 



Highest 88, 28th 



Lowest 18, 6th 



Mean 49.2 



R-nge 70 



Highest mean daily 69.5, 28th 



Lowest mean daily 28.5, 6th 



Mean maximum 61 



Mean minimum 37.3 



Greatest daily range 40, 20th 



Least daily range 5, 9th 



Precipitation 



Precipitation. In inches 3.07 



Snow, in inches 25 



Maximum precipitation in 24 hrs. 



1.33, 8th, 9th 

 Number of days on which .01 or more 



inches of precipitation fell 11 



Wind (miles) 



Total movement 4519 



Greatest daily movement .... 352, 10th 



Least daily movement 39, 26th 



Mean hourly velocity 6.3 



Maximum velocity, 5 min., ... 40, 10th 



Wind (direction) 



Prevailing direction w 



North, days 3 



Northeast, days 1 



East, days 2 



Southeast, days 5 



South, days 3 



Southwest, days 4 



West, days 3 i 



Northwest, days 9 \ 



Weather 



Mean relative humidity, per cent. . 58.5 



Mean cloudiness, per cent 52 



Number of clear days 15 



Number of fair days ... 8 



Number of cloudy days 7 



Number of hours bright sunshine . . 256 

 Percent of possible hours of bright 



sunshine 63.7 



Thunder and lightning 1st, 20th, 29th 



Frosts after 15th none 



30.48 



29.41 



29.99 



1.08 



79.5 

 21.6 

 45.8 

 57.8 



3.27 

 2.32 



11 

 5,436 



7.5 

 29 



62.0 



49.2 



11 



10 



9 



221 



55 



30.71, 1911 

 28.99, 1907, 1929 



1,52,1930; 0.72,1919 



88.5, 1896 

 8.5, 1923 



6.89, 1929; 0.76, 1892 

 11, 1891; 0, 1910 



18, 1909; 3, 1892 

 ,208, 1808; 3,853, 1917 



40, 1935 



75, 1901; 34, 1925, 1927 



19, 1911; 3, 1898, 1902 



18, 1915; 2, 1894, 1901 



22, 1901; 3, 1899, 1924 



296,1911; 103,1901 



Nope— The first colnrnn in the abo%'e summary irives observations made during the 

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

 to 19v!«. except that humidity records are l)ased on observations made from 1929 to 1987. 

 The third column uivea extremes observed from 1889 to 1937 



