BULLETIN No. 378. 



JUNE, 1920 



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, 2jj.^ ft. 

 Height of Wind Instnitnents ^2 ft. Time used, y^thAfer. 



MONTHLY SUMMARY. 



Pressuie. In inches. 

 Maximum reduced to freezing, 30.04, 27th, g A 

 Minimum reduced to freezing, 29.29, i6th, 2 p 

 Reduced maximum reading . 30.32, 27th, 9 A 

 Reduced minimum reading, 29.54, i6tli, 2 p 



Mean semi-daily reduced 29.952 



Monthly range 0.78 



*Air Tempera<ure. In Degrees Fahr. 



Highest SS.o, nth, 2 p; 27th, 4 P 



Lowest 45-0, 20th, 6 A 



Mean hourly 64.5 



Mean of means of max. and min 64.7 



Mean sensible (wet bulb) 59-4 



Mc)nthly range 43-o 



Highest mean daily 73-6. 2d 



Lowest mean daily 50.3, iSth 



Mean maximum 75-3 



Mean minimum 541 



Mean daily range 21.2 



Greatest daily range 35.5,10th 



Least daily range 6.0, 18th 



Hamidity. 



Mean dew point 56-9 



Mean force of vapor 618 



Mean relative humidity 77.5 



Precipitation. In inches. 



Total precipitation, in inches 6.26 



Number of days on which .01 inch or more 



rain fell 



•Temperature in ground shelter. 



•'Reduced to freezing and sea-level. 



Wind. 



Total movement 3055 m 



Greatest daily movement 201m, 7tli 



Least daily movement 30m, 24th 



Mean daily movement 102m 



Mean hourly velocity 4.2m 



Maximum pressure per square foot, 3.5 lbs = 



26m per hour, 2gth, 3 p, S. 

 Maximum velocity for 5 minutes, 24m per 



hour, 29th, 2P, S. 

 Prevailing direction. North. 



Summary. 



North Northeast 23 per cent 



North Northwest 10 " " 



South 23 ■' " 



South Southwest 10 " " 



Other directions 34 " 



Weather. 



Mean cloudiness observed .... 51 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 216 hours = 47 per cent. 



Number of clear days 9 



Number of fair days 13 



Number of cloudy days 8 



Bright Sunshine. 



Number hours recorded, 241 hrs, 53 = per cent. 

 Rain. 3d, 5th. 6th, 13th, 15th, 16th, 17th, 



18th, 2ISt, 22d, 2Sth, 29th, 30th. 



Thnnder and Lightning. 15th, 29th, 30th. 

 Hail. 29th. 

 Gnles. ncjiie. 



