BULLETIN No. 342. 



JUNE, 1917 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATIOIN. 



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



Height of barometer above ground, 51 ft. Above sea level, 2'jj.^ ft. 

 Height oj Wind Instrutnents 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.04, 13th, 7 a 

 Minimum reduced to freezing, 29.46, 29th, S p 

 Reduced! maximum reading, 30.33, i3ht, 7 A 

 Reduced! minimum reading, 29.75, 3rd, 3 p, 

 29th, Sp 



Mean semi-daily reduced 29.995 



Monthly range 5S.0 



*Air Temperature. In Degrees Fahr. 



Highest 88.0, 22d, 2 p 



Lowest 50.0, i8th, 2 A 



Mean hourly 65.3 



Mean of means of max. and min 66 3 



Mean sensible (wet bulb) 60.1 



Monthly range 38.0 



Highest mean daily 72.6, 20th 



Lowest mean daily 55.4, ist 



Mean maximum 76.3 



Mean minimum 56.0 



Mean daily range 20.3 



Greatest daily range 33.0, 22d 



Least daily range 6.0, nth 



Humidity. 



Mean dew point 57.4 



Mean force of vapor 611 



Mean relative humidity 78. 3 



Precipitation. In inches. 



Total precipitation, in inches 5.27 



Number of days on which .01 inch or more 



rain fell 16 



♦Temperature in ground shelter. 

 **Reduced to freezing and sea-level. 



Wind. 



Total movement 20S1 m 



Greatest daily movement 176m, 5th 



Least daily movement 5m, nth 



Mean daily movement 69 m 



Mean hourly velocity 2.9 m 



Maximum pressure per square foot, 8.0 lbs = 



40m per hour, 3rd, 6 p, N.W. 

 Maximum velocity for 5 minutes 27m per 



hour, 3rd, 6 p, .N.W. 

 Prevailing direction. Northwest. 



Summary. 



North Northwest 20 per cent 



South 17 



Southwest 17 



West Southwest 10 



South Southwest 10 



Other directions 26 



Weather. 



Mean cloudiness observed .... 49 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 207 hours = 45 per cent 



Number of clear days 6 



Number of fair days 15 



Number of cloudy days 9 



Bright Sunshine. 



Number hours recorded, 250 hrs, = 55 per cent. 

 Rain. 3d, 5th, 6th, 7th, 8th, loth, nth, 12th, 



14th, 15th, i6th, 17th, 22d, 24th, 25th, 26th, 



27th, 29th. 

 Thunder and Lightninii, Ttli, Stii, 14th, 22d, 



24th, 26th, 27th, 29th. 

 Gales, 35 or more miles per hour. 40m, 3d, 



N.W. 



