MONTHLY SUMMARY 



December, 1948 



Normal 



Extremes 



30.66 



29.27 



30.06 



1.38 



54.3 



-1.09 



27.5 



56.2 



Barometer, in inches 

 (Readings reduced to sea level) 



Maximum 30.47, 26th 



Minimum 28.92, 31st 



Mean semi-daily 29.976 



Range 1.55 



Air Temperature, in degrees F. I 



Highest 58, 30th 



Lowest 2. 27th - 



Mean 32.4[ 



Range 56 



Highest mean daily 54, 30th 



Lowest mean daily 10. .5, 25th 



Mean maximum 40.0 



Mean minimum 24.6 



Greatest daily range 33, 29th 



Least daily range 3, ISth 



Degree-days of heating load for month 1011 

 Degree-days cumulative for season ....2099 j 



Precipitation, in inciies | 



Precipitation 2. 87 



Snow 1.0 1 



Maximum precip. in 24 hrs 1.03. 30th[ 



Number of days with .01 or more 11 



Wind in miles ! 



Total movement 3404 



Greatest daily movement 367, 31st 



Least daily movement 25, 21st 



Mean hourly velocity 4.6 



Maximum velocity 48, 30th 



Wind, direction 



Prevailing direction NW 



North, days 5 



Northeast, days 2 



East, days 1 



Southeast, days 2 



South, days 7 



Southwest, days 1 



West, days 4 



Northwest, days 9 



Weather 



:\Iean relative humidity, percent 76 69.4 



Mean cloudiness, percent 50 54.9 



Number of clear days 8 



Number of fair days 6 9 



Number of cloudy days 25 14 



Number of hours bright sunshine 27 128 



Percent of possible hours of 



bright sunshine 0.5 45.2 



Thunder and lightning — 



First snow — Nov. 6 



3.39 



8.50 



10 

 4710 



6.3 



31.4 



WNW 



30.96, 1889 

 28.85, 1915 



1.7S, 1895; 1.01, 1892 



65.5, 1908 



—22.5, 1917 



36.9. 1891; 17.1, 1917 



7.77. 1901; .58, 1943 

 26.50, '02, T, 1891, 1943 



17, 1902; 4, 1892, 1943 

 6,694, 1925; 3,239, 1918 



48, 1938, 1943, 1944 



71, 1929; 39, 1919 



15, 1890: 2, 1922, 1933 



16, '09; 4, 'S9,'30.'31,'36,'38 



23, '33; 7, '09, '23 



172, 1896; 63, 1933 



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. 



