BULLETIN No. 392. 



AUGUST, 192 1 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



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

 Height oj Wind Instriitnents 22 ft. Time used, y^thMer. 



MONTHLY SUMMARY. 



Pressnie. In inches. 

 Maximum reduced to freezing, 30.06, 26th, 8 A 

 Minimum reduced to freezing, 29.33, 18th, i P 

 Reduced maximum reading . 30.35, 26th, 8 a 

 Reduced minimum reading, 29.61, i8th, i p 



.Mean semi-daily reduced 30067 



Monthly range 0.74 



Air Temperature. In Degrees Fahr. 



Highest 91.0. 30th, 4 p 



Lowest 45.0, 23d, 6 a 



Mean hourly 66.9 



Mean of means of max. and min 67.2 



Mean sensible (wet bulb) 61.2 



Monthly range 46.0 



Highest mean daily 78.2. 30th 



Lowest mean daily W-S^ 22d 



Mean maximum 79-2 



Mean minimum 55-1 



Mean daily range 24.2 



Greatest daily range 35-5 loth 



Least daily range 9-°! 2d 



Homidity. 



Mean dew point 57-9 



Mean force of vapor 638 



Mean relative humidity 77- 



Precipitation. In inches. 



Total precipitation, in inches 2.35 



Number of days on which .01 inch or more 

 rain fell 9 



•Temperature in ground shelter. 

 ••Reduced to freezing and sea-level. 



Wind. 



Total movement 3709 m 



Greatest daily movement . . . 224m, ist, 7th 



Least daily movement 39m, 23d 



Mean daily movement 120m 



Mean hourly velocity 5.0m 



Maximum pressure per square foot, 5.0 lbs= 



32m per hour, ist, 10 a, N.W., also 15th, 



12 M, N.N.W. 

 Maximum velocity for 5 minutes, 20m per 



hour, 15th, 2 p, N.W. 

 Prevailing direction. Southwest. 



Summary. 



South Southvk'est 32 per cent 



North Northeast 13 " " 



Northwest 13 " " 



Other directions 42 " " 



Weather. 



Mean cloudiness observed .... 40 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 112 hours = 26 per cent. 



Number of clear days 17 



Number of fair days 11 



Number of cloudy days 3 



Bright Sunshine. 



Number hours recorded, 317, = 74 per cent. 

 Rain, 2d, 6th, 7th. 8th, 12th, 13th, 14th, 17th, 



iSth, 20th, 30th. 

 Thunder and Li^htnin^, 7th, 14th, 17th, 



18th, 30th. 

 Gales. None 



