MONTHLY SUMMARY 



May, 1947 



Extremes 



Barometer, in inches 



(Readings reduced to sea level) 



Maximum 30.32, 10th 



Minimum 29.50, 6th 



Mean semi-dailv 29.968 



Range ' 0.82 



Air Temperature, in degrees F. 



Highest 87, 13th. 24th 



Lowest 28, 10th 



Mean 56.1 



Range 59 



Highest mean daily 74.5. 29th 



Lowest mean daily 40.0. 8th 



Mean maximum 67.1 



Mean minimum 45.0 



Greatest daily range 39, 11th 



Least daily range 5, 2nd, 3rd 



Precipitation, in incties 



4.63 



Precipitation 



Snow — 



Maximum precip. in 24 hrs 2.10, 2Sth 



Number of days with .01 or more 14 



Wind, in miles 



Total movement 4762 



Greatest daily n.ovement 349, 8th 



Least daily movement 69, 23rd 



Mean hourly velocity 6.4 



Maximum velocity 29, 9th 



Wind, direction 



Prevailing direction NW 



North, days 8 



Northeast, days 1 



East, days 2 



Southeast, days 4 



South, days 5 



Southwest, days 2 



West, days 2 



Northwest, days 7 



Weather 



Mean relative humidity, percent 63.6 



Mean cloudiness, percent 52.0 



Number of clear days 10 



Number of fair days 11 



Number of cloudy days 10 



Number of hours bright sunshine 225 



Percent of possible hours of 



bright sunshine 50 



Thunder and lightning 25th, 29th 



30.39 



29.51 



29.96 



0.88 



86.1 

 31.2 

 57.1 

 54.9 



3.60 

 12 



4504 



6.1 

 28.8 



W 



60.7 



52.1 

 11 

 11 



9 



252 



55.6 



30.62, 1936 

 29.10, 1938 



94.5, 1896, 1911 

 24.0. 1900 



7.44, 1931; .48. 1903 

 20, 1901, 1945; 5, 1903 



5946, 1907; 2180, 1894 

 45, 193 5 



70, 1901, 1902; 30, 192 3 



21, 1944; 0. 1927 



17, 1907, 1926; 5, 1923 



20, 1927; 2, 1941 



350, 1944; 137, 1927 



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 1946. 



