MONTHLY SUMMARY 



January 1940 



Normal 



Extremes 



Barometer, in inches 



(Readings reduced to sea level) 



Maximum 30.53, 10th 



Minimum 29.53, 1st, 2nd 



Mean semi-daily 29.992 



Range l.CO 



Air Temperature, in degrees F. 



Highest 42, 15th 



Lowest - 3, 10th 



Mean 18.5 



Range 45 



Highest mean daily 37, 15th 



Lowest mean daily 9, 1 7th 



Mean maximum 27.1 



Mean minimum 9.S 



Greatest daily range 32, 1 1th 



Least daily range 4, 14th 



Precipitation, in inches 



Precipitation 2,63j 



Snow 5 75 



Max. precipitation in 24 hrs. 2 1 1, 14th, 15th 

 Number of days with 01 or more 7 



Wind, in miles 



Total movement 5091 



Greatest daih- movement 368, 16th 



Least daily movement 33, lOth, 11th 



Mean hourlv velocit\- 6 8 



Ma.\imum velocitx- . ." 39, 28th 



Wind, direction 



Prevailing direction W'NVV 



North, days 3 



Northeast, days 



East , days 



Southeast, days 1 



South, days 1 



Southwest, days 5 



West , days 1 



Northwest, days \') 



Weather 



Mean relative humidity, percent 74 8 



Mean cloudiness, percent 42 



Number of clear days 14 



Number of fair days 9 



Number of cloudy days 8 



Number hours bright sunshine 171 



Percent of possible hours of bright 



sunshine 58.2 



30.70 



29.20 



30.07 



1.50 



51.1 

 -7.1 

 24.2 

 58.2 



3.61 

 13.24 



11 



5055 



6.8 

 32.7 



WNW 



70.1 



55 



9 



9 



13 



137 



46.7 



31.00, 1927 

 28.55, 1913 



2.18, 1913; 0.97, 1896 



66.0, 1932 



-26.0, 1904 



34.2, 1913; 13.9, 1918 



7.15, 1898; 1.07, 1896 

 33,1898, 1923; 1.50, '08 



15, '93, •20;4, 1901 



7770, 1908; 2896, 1895 



47, 1938 



78, 1932; 37, 1908 



17, 1939;2, 1914 



18, 1890, 1926; 3, 1916 



22, 1923, 1931; 4, 1920,1939 



214, 1920; 74, 1932 



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 1939 



