MONTHLY SUMMARY 



May, 1948 



Barometer, in inches 

 (Readings reduced to sea level) 



Maximum 30.06, 6th 



Minimum 29.28, 8tli, 21st, 22d 



Mean semi-daily 29.901 



Range 0.78 



Air Temperature, in degrees F. 



Highest 81, 10th, 11th, 12th 



Lowest 31, 2nd 



Mean 57.3 



Range 50 



Highest mean daily 69.5, 29th 



Lowest mean daily 47.0, 8th, 14th 



Mean maximum 67.0 



Mean minimum 47.6 



Greatest daily range 38, 2nd 



Least daily range 4, 14th 



Degree-days of heating load for 



month 256 



Degree-days cumulative for season ..6920 



Precipitation, in inches 



Precipitation 5.83 



Maximum precip. in 24 hrs 0.98, 16th 



Number of days with .01 or more 16 



Wind in miles 



Total movement 3814 



Greatest daily movement 264, 1st 



Least daily movement 31, 26th 



Mean hourly velocity 5.1 



Maximum velocity 28, 10th, 15th 



Wind, direction 



Prevailing direction ESE 



North, days 6 



Northeast, days 2 



East, days 3 



Southeast, days 9 



South, days 1 



Southwest, days 4 



West, days 3 



Northwest, days 3 



Weather 



Mean relative humidity, percent 69.4 



Mean cloudiness, percent 72.0 



Number of clear days 5 



Number of fair days 7 



Number of cloudy days 19 



Number of hours bright sunshine 134 



Percent of possible hours of 



bright sunshine 29.6 



Thunder and lightning 16th 



Normal 



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 



Extremes 



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, 1935 



70. 1901, 1902; 30, 1923 



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 observa- 

 tions 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 1947. 



