AMHERST, MASS. 



BULLETIN No. 400. 



APRIL. 1922 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



Latitude, 42° 23' 48.5" N. Longitude 72* 31' 10" \V. 



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

 Height oj Wind Instruments 72 ft. Time used, y^thMer. 



MONTHLY SUMMARY. 



Pressuie. In inches. 

 Maximum reduced to freezing, 30.12, 6th, 9 a 

 Minimum reduced to freezing, 29.09, iith, 6 p 

 Reduced maximum reading 30.43. 6th, 9 .\ 



Reduced minimum reading, 29.38, nth, 6 P 



Mean semi-daily reduced 30.042 



Monthly range 1.05 



Air Temperature. In Degrees Fahr. 



Highest 81.5, loth,; 330 p 



Lowest 24.5, 22nd, 6 A 



Mean hourly 45.7 



Mean of means of max. and min 45.8 



Mean sensible (wet bulb) 41. i 



Monthly range 57.0 



Highest mean daily 60.7. loth 



Lowest mean daily 32.3, ist 



Mean maximum 57.2 



Mean minimum 34.4 



Mean daily range 22.8 



Greatest daily range '. 43.5 loth 



Least daily range 4.5, 7th 



Hnmidity. 



Mean dew point 35.7 



Mean force of vapor 306 



Mean relative humidity 73.2 



Precipitation. In inches. 



Total precipitation, in inches 2.81 



Number of days on which .01 inch or more 



rain fell 11 



Total Snow in inches i\ 



Days of sleighing 2 



•Temperature in ground shelter. 

 ••Reduced to freezing and sea-level. 



Wind. 



Total movement 5661 m 



Greatest daily movement 35om, 27th 



Least daily movement 21m, 4th 



Mean daily movement iSgm 



Mean hourly velocity 7.gm 



Maximum pressure per square foot. 14.0 lbs = 



53m per hour, 20th, 3 p, W.N.W. 

 Maximum velocity for 5 minutes, 36 m per 



hour, 20th, 3 p., W.N.W. 

 Prevailing direction, Northwest. 

 Summary. 



North 17 per cent 



South Southwest '3 " " 



West Northwest 27 " " 



Northwest 17 " " 



Other directions 28 " " 



Weather. 



Mean cloudiness observed .... 40 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 174 hours = 43 per cent. 



Number of clear days 15 



Number of fair days 5 



Number of cloudy days 10 



Bright Sunshine. 

 Number hours recorded, 228, = 57 per cent. 

 Rain, ist, 2d, 4th, 7th, 8th. nth, 15th, 17th, 



i8th, ii^th, 20th, 23d, 27th. 

 Snow, ist, 2d, 20th, 23d. 

 Hail. 



Frosts,— after the 15th— 16th, 21st, 22d, 23d, 

 24th, 25th, 29th. 



Thunder and Liithtnintl, nth. 



Gales. 36m, 17th, S.SW.; 45m, i8th, W.; ;3m, 

 20th, W.N.W.: 40m, 2ist, W.N.W.; 3;m, 

 24th, N.N. E.; 45ni, 27th, W.N.W.: 39m, 

 2Sth, N. W.: 36m, 29th, W. N. W.: 35ni, 

 30th, N.N. W. 



