Monthly Summary 



December, 1929 



Normal 



Extremes 



Barometer 



(Readings reduced to sea level) 



Maximum. . . .^ 30.72,12th 



Minimum 29.42, 29th 



Mean semi-daily 30.049 



Range 1.30 



Air Temperature 



Highest 46.0, 14th 



Lowest 1.0, 12th 



Mean 28.1 i 



Monthly range 45.0 



Highest mean daily 38.5, 31st 



Lowest mean daily 11.0, 12th 



Mean maximum 34.2 



Mean minimum 21.9 



Greatest daily range 20.0, 12th 



Least daily range 2.0, 29th 



Precipitation 



Precipitation. In inches 4.05 



Snow, in inches 8 



Maximum precipitation in 24 hrs. 0.74, 



17th, 18th. 

 Number of days on which .01 or 



more inches of rain fell 12 



Wind (miles) 



Total movement 4320 



Greatest daily movement 297, 24th 



Least daily movement 22, 18th 



Mean hourly velocity 5.8 



Maximum velocity for 5 min .... 33, 31st 



(corrected to c<jnform to 3 cup anemometer) 

 Wind (direction) 



Prevailing direction wsw 



North, days 



Northeast, days 



East, days 3 



Southeast, days 4 



South, days 2 



Southwest, days 6 



West, days 7 



Northwest, days 9 



Weather 



Mean relative humidity, per cent. . 76.0 



Mean cloudiness, per cent 71.0 



Number of clear days 8 



Number of fair days 7 



Number of cloudy days 16 



Number of hours bright sunshine 91.9 

 Percent of possible hours of bright 



sunshine 33 



Thunder and lightning 19th 



30.65 



29.25 



30.056 



1.40 



54.5 

 -2.3 

 27.3 

 56.8 



3.47 

 8.99 



4726 



6.4 

 29 



77.2 



53.4 



8 



10 



13 



130.7 



46 



30.96, 1889 

 28.85, 1915 



1.78, 1895; 1.01, 1892 



65.5, 1908 

 -22.5, 1917 



7.77, 1901; 0.87, 1896 

 26.50, 01, 02; t, 1891 



17, 1902; 4, 1892 

 6694, 1925; 3239, 1918 



41, 1928 



87.1 1919'; 67.2, 1890 



68, 1897; 39, 1919 



15, 1890; 2, 1922 



16, 1909; 4, 1889 



19, 1911, 1922; 7, 1909, 1923 



172, 1896; 86, 1922 



Note— The first column in the above summary gives observations made during the 

 month. The second and third columns give the averages and extremes observed irom 18S9 

 to 1928 for the same month of the year. 



