BULLETIN No. 367. 



JULY. 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, 51 ft. Above sea level, 2"/^.^ ft. 

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



MONTHLY SUMMARY. 



Pressnie. In inches. 

 Maximum reduced to freezing, 30. 07, gth, 4 a 

 Minimum reduced to freezing, 29.30, nth, i A 

 Reduced maximum reading . . 30.37, gth, 4 A 

 Reduced minimum reading, 29.59, nth, i A 



Mean semi-daily reduced 29.972 



Monthly range 0.78 



♦Air Temperature. In Degrees Fahr. 



Highest 98.0, 4th, 1:30 P 



Lowest 49-0, 12th, 5 A 



Mean hourly 7i-8 



Mean of means of max. and min 71.8 



Mean sensible (wet bulb) 65.9 



Monthly range 49.0 



Highest mean daily 85.4, 5th 



Lowest mean daily 61.0, nth 



Mean maximum 83.4 



Mean minimum 60.2 



Mean daily range 23.2 



Greatest daily range 43.0, ist 



Least daily range 5.5, 22d 



Humidity. 



Mean dew point 63.5 



Mean force of vapor 772 



Mean relative humidity 77.1 



Precipitation. In inches. 



Total precipitation, in inches 4.17 



Total snow, in inches 



Number of days on which .01 inch or more 



rain fell 15 



•Temperature in ground shelter. 

 ••Reduced to freezing and sea-level. 



Wind. 



Total movement 371901 



Greatest daily movement 295m, 22d 



Least daily movement 35ni, lyt'i 



Mean daily movement 120m 



Mean hourly velocity 5.0 m 



Maximum pressure per square foot, 4.0 lbs 



28m per hour, gth, 2P, S. 

 Maximum velocity for 5 minutes, 21 m per 



hour, 28th, IP, S. 

 Prevailing direction, South Southwest. 



Summary. 



South 45 per cent 



South Southwest 10 " " 



Southwest 13 ■' " 



North Northeast 10 " " 



North 10 " " 



Other directions 12 " " 



Weather. 



Mean cloudiness observed .... 45 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 139 hours = 30 per cent. 



Number of clear days 15 



Number of fair days 12 



Number of cloudy days 4 



BriiJht Sunshine. 



Number hours recorded, 323 hrs,= 70 per cent. 

 Rain. 5th. 6th, 7th, loth, nth. 15th, i6th, iSth, 



19th, 2lSt, 22d, 23d, 24th, 26th, 31st. 



Thunder and Liiihtniiiii, 6th. loth, nth, 



24th, , 26th. 

 Gules. 35 miles or more per hour : None. 



