BULLETIN No. 353. 



MAY, 19 18 



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, 2yj.^ ft. 

 Height oj Wind Instriunents 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.20, i6th, 6 a 

 Minimum reduced to freezing, 29.22, loth, 6 p 

 Reduced maximum reading . . 30.50, i6th, 6 a 

 Reduced! minimum reading, . 29.51, lotli, 6 p 



Mean semi-daily reduced 30.061 



Monthly range 0.99 



*Air Temperatnre. In Degrees Fahr. 



Highest 86.5, 7th, 2 p; 



2Sth, 4:30 P 



Lowest 36.0, 2d, 5 A 



Mean hourly 62.1 



Mean of means of max. and min 62.2 



Mean sensible (wet bulb) 55.7 



Monthly range 505 



Highest mean daily 7.^.0, 28th 



Lowest mean daily 31.2, ist 



Mean maximum 74.8 



Mean minimum 49.7 



Mean daily range 25.1 



Greatest daily range 38.0, iSth 



Least daily range 7.5,30th 



Humidity. 



Mean dew point 53.1 



Mean force of vapor 545 



Mean relative humidity 72.2 



Precipitation. In inches. 



Total precipitation, in inches 2.47 



Total snow, in inches 



Number of days on which .01 inch or more 



rain fell 12 



'Temperature in ground shelter. 

 **Reduced to freezing and sea-level. 



Wind. 



Total movement 4906 m 



Greatest daily movement 345m, loth 



Least daily movement 57m 22d 



Mean daily movement i5Sm 



Mean hourly velocity 6.6 m 



Maximum pressure per square foot, 6.5 lbs = 



36m per hour, 6th, 3 p, S.S.W.; loth, 4P, S. 

 Maximum velocity for 5 minutes, 24m per 



hour, loth, 4 p, S. 

 Prevailing direction. South Southwest. 



Summary. 



South 23 per cent 



South Southwest 29 " •' 



Other directions 48 " " 



Weather. 



Mean cloudiness observed .... 51 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 195 hours = 43 per cent 



Number of clear days 7 



Number of fair days 16 



Number of cloudy days 8 



Bright Sunshine. 



Number hours recorded, 258 hrs, = 57 per cent 

 Rain, ist, 6th, loth, 12th, 13th, 14th, 21st, 



22d, 25th, 27th, 29th, 30th, 31st. 



Thunder and Lightning. 6th, loth, 27th. 

 Frosts, None. 



Gales, 35 miles or more per hour : 36m. 

 6th, S.S.W.; 35m, Sth, S.W.; 36m, loth, S. 



