BULLETIN No. 356. 



AUGUST, 19 18 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTUKAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, ^^ fi- Above sea level, zyj.^ ft. 

 Height oj IVitid Instruments 72 ft. Time used, 7^th Mer. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30. ,19 19th, 9 A 

 Minimum reduced to freezing, 29.44, 9th, 4 p 

 Reduced maximum reading . . 30.48, 19th, 9 A 

 Reducedt minimum reading, . 29.72, 9th, 4 p 



Mean semi-daily reduced 30.027 



Monthly range 0.76 



*Air Temperature. In Degrees Fahr. 



Highest loo.o, 7th, 3 p 



Lowest 44.0,19th, 6 a.: 



20th, 6 A. 



Mean hourly 70.5 



Mean of means of max. and min 71.6 



Mean sensible (wet bulb) 63.9 



Monthly range 56 o 



Highest mean daily 81.7, 7th 



Lowest mean daily 60.9, 19th 



Mean maximum 84.5 



Mean minimum 5: 



Mean daily range 2 



Greatest daily range 42.5, 20th 



Least daily range 13.0,29th 



Huoiidiiy. 



Mean dew point 60.8 



Mean force of vapor 724 



Mean relative humidity 75,5 



Precipitafiou. In inches. 



Total precipitation, in inches 2.22 



Number of days on which .01 inch or more 



rain fell 10 



•Temperature in ground shelter. 

 **Reduced to freezing and sea-level. 



Wind. 



Total movement 25S3m 



Greatest daily movement 145m, 17th 



Least daily movement 24m j6th 



Mean daily movement '83 m 



Mean hourly velocity 3-5 m 



Maximum pressure per square foot, 6.5 lbs = 



36m per hour,''i4th, 3 p, S.W. 

 Maximum velocity for 5 minutes, 24m per 



hour, 14th, 3:30 p, S.W. 

 Prevailing direction. South. 



Summary. 



South 39 per cent. 



South Southwest 19 " ■' 



Southwest 10 " " 



North Northeast 10 " " 



Other directions 22 " " 



Weather. 



Mean cloudiness observed .... 37 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 153 hours = 36 per cent 



Number of clear days 12 



Number of fair days . . . ; 12 



Number of cloudy days '7 



Bright Sunshine. 



Number hours recorded, 276 hrs, = 64 per cent 

 Rain. 5th, 7th, 9th, loth, nth, 14th, 24th, 



26th; 29th, 31st. 

 Thunder and Lightnina. 2d, 9th, I4th,24th, 



26th, 31st. 

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



14th, S. W. 



