BULLETIN No. 337. 



JANUARY, 1917 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



Latitude, 42° 23' 48.5" N. Longitude 72* 31' 10" W. 



Height of barometer above ground, ST ft. Above sea level, 2^^.^ ft. 

 Height oj IVind Instrutnents 72 ft. 



MONTHLY SUMMARY. 



Pressoie. In inches. 

 Maximum reduced to treezing, 30.42, iSth, 10 A 

 Minimum reduced to freezing, 29.05, loth, 5 p 

 Rediicedt maximum reading, 30.74, 15th, 10 A 

 Reducedt minimum reading, 29.36, loth, 5 P 



Mean semi-daily reduced 30.007 



Monthly range 1.38 



*Air Temperature. In Degrees Fahr. 



Highest 47,5, 14th, 8:30 A 



Lowest -3.5, 27th, 6 A 



Mean hourly 23.1 



Mean of means of max. and min 23.5 



Mean sensible (wet bulb) 21.3 



Monthly range 510 



Highest mean daily 36.4, 9th 



Lowest mean daily , . . . 5.4, 12th 



Mean maximum 31.7 



Mean minimum 15.3 



Mean daily range 16.4 



Greatest daily range 32.5, 27th 



Least daily range 3.0, 5th 



HnmiditF. 



Mean dew point 17.6 



Mean force of vapor 133 



Mean relative humidity 82.4 



Precipitation. In inches. 



Total precipitation, in inches 3.64 



Total snow, in inches 15 



Number of days on which .01 inch or more 



rain fell 9 



Days of Sleighing 



* Temperature in ground shelter. 



t Reduced to freezing and sea-level. 



Wind. 



Total movement 4701 m 



Greatest daily movement 391m, 19th 



Least daily movement 7m, 14th 



Mean daily movement 152 m 



Mean hourly velocity 6.3 m 



Maximum pressure per square foot, 16.0 lbs = 



57m per hour, 14th, 9 A, S.S.W. 

 Maximum velocity for 5 minutes 36m per 



hour, 14th, 9A, S.S.W. 

 Prevailing direction, West. 



Summary. 



North Northwest 10 per cent 



West 10 " 



West Southwest 10 ' 



Northwest 19 " 



West Northwest 16 " 



Southwest 13 " 



Other directions 22 " 



Weather. 

 Mean cloudiness observed .... 64 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 163 hours = 55 per cent 



Number of clear days g 



Number of fair days 6 



Number of cloudy days 16 



Bright Sunshine. 



Number hours recorded, 131 hrs, = 45 per cent 



Rain. 5th, 14th, 31st. 



Snow, 3d, 13th, i8th, 2ist,22d, 25th, 26th,27th. 



28th, 29th, 31st. 

 Hail. 13th. 

 Gales, 35 or more miles per hour. 36m, 6th, 



N.N.W.; 45m, 7th, N.W.; 35m, nth, N.; 



35m,i2th,N.N.W.; 57m, 14th, S.S.W.; 35m, 



17th, W.N. W.; 41m, 19th, N.W.; 46m, 22d, 



N.W.: 37m, 25th, N.W. 



