BULLETIN No. 351. 



JANUARY, 1919 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, ^i ft. Above sea level, 2'/j.^ ft. 

 Height oj Wind Instruments y 2 ft. Time used, y^th Mer. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.34, 12th, g a 

 Minimum reduced to freezing, 29.02, 24th, 5 A 

 Reduced maximum reading . . 30.68, 12th, 9 a 

 Reduced minimum reading, . 29.33, 24th, 5 A 



Mean semi-daily reduced 30.008 



Monthly range 1.35 



*Air Temperatnre. In Degrees Fahr. 



Highest 540, 2d, 3 A 



Lowest -8.^, 12th, 7:30A 



Mean hourly 28.1 



Mean of means of max. and min 28.7 



Mean sensible (wet bulb) 25.1 



Monthly range 62.5 



Highest mean daily 39.5, 2d 



Lowest mean daily 3.5, 12th 



Mean maximum 37,7 



Mean minimum ". . 19.8 



Mean daily range 18.0 



Greatest daily range 34.5, 13th 



Least daily range 4-5i3d 



Hnmidity. 



Mean dew point 21. i 



Mean force of vapor 156 



Mean relative humidity 79.6 



Precipitation. In inches. 



Total precipitation, in inches 2.02 



Total snow, in inches 6.( 



Number of days on which .01 inch or more 



rain fell 8 



Days of sleighing, 20 



•Temperature in ground shelter. 

 "Reduced to freezing and sea-level. 



Wind. 



Total movement 4554 m 



Greatest daily movement 355m, nth 



Least daily movement 10m, ist 



Mean daily movement 144 m 



Mean hourly velocity 6.o°m 



Maximum pressure per square foot, 12.0 lbs = 



50m per hour, nth, 7 A, N.W. 

 Maximum velocity for 5 minutes, 36m per 



hour, nth, 7 a, N.W. 

 Prevailing direction. West. 



Summary. 



Southwest 13 per cent. 



South -Southwest 10 



West Northwest 23 



West 10 



Northwest 10 



West Southwest 10 



Other directions 24 



Weather. 



Mean cloudiness observed .... 52 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . .128 hours = 44 per cent 



Number of clear days 9 



Number of fair days 13 



Number of cloudy days 9 



Bright Sunshine. 



Number hours recorded, 166 hrs, = 56 per cent 



Rain, ist, 2d, 23d, 24th. 



Snow, 2d, 3d, 4th, 7th, 8th, gth, 17th, 29th. 



3'st. 

 Gales, 35 miles or more per hour I35ni., 



loth, N.W.;1 50m, nth, N.W.; 37m, 24th, 



W.N.W.; 36m, 31st, N.W. 



