LIBRAHY OF THE 



MassachiistUs Agricultural ColU-r 



AMHERST, MASS. 



BULLETIN No. 425. 



MAY, 1924 



Meteorolodcal Observations 



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, 273-5.fi- 

 Height oj Wind Instnitnents J2 ft. I'itne used, j^thMer. 



MONTHLY SUMMARY. 



Pressuie. In inches. 



Maximum reduced to freezing 29.94, nth, 8 A. 

 Minimum reduced to freezing, 28.96, ist. 6 A. 

 Reduced maxinuim reading, 30.24, nth, 8 a. 

 Reduced minimum reading, 29.26, ist, 6 .\■ 

 ^lean semi-daily reduced 29.S51 



Monthly range 0.9S 



Air Temperature. In Degrees Fahr. 



Highest 74.0, 17th, 4 p. 



Lowest 33.0,23rd, 5:30 a. 



Mean hourly 53.5 



Mean of means of max. and min 53.2 



Mean sensible (wet bulb) 47 6 



Monthly range 41.0 



Highest mean daily 62.4, 17th, iSth 



Lowest mean daily 44.1, loth 



.Mean maximum 63.0 



Mean minimum 434 



Mean daily range 19.6 



Greatest daily range 34.5, 23d 



Least daily range .5.0,10th 



Humidity. 



Mean dew point 42.3 



Mean force of vapor 403 



Mean relative humidity 70.3 



Precipitation. In inches. 



Total precipitation, in inches 2.21 



Number of days on which .01 inch or more 

 rain fell 15 



Wind. 



Total movement 5'35m 



Greatest daily movement 3)4mi i8th 



Least daily movement 45m, 20th 



Mean daily movement i66m 



Mean hourly velocity 6.9m 



Maximum pressure per square foot, 13.5 lbs = 



52m per hour, 18th, 3 p., S. 

 Maximum velocity for 5 minutes, 30m per 



hour, iSth, 3 p., S. 

 Prevailing direction. West. 

 Summary. 



.South Southwest 19 per cent 



Southwest 16 " 



West 13 " 



Northwest 10 " 



North Northeast 10 " 



Other directions 32 " 



Weather. 



Mean cloudiness observed .... 54 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 1S8 hours = 42 per cent. 



Number of clear days n 



Number of fair days n 



Number of cloudy days 9 



Britibt Sunshine. 



Number hours recorded, 265 = 58 per cent. 



Rain. 3d, 4th, 6th, 9th, lotli, nth, 12th, 15th, 

 16th, 18th, 20th, 2ist, 22d, 24th, 27th, 28th. 



Thunder and Liiibtnin^, 4th, 24th. 



Frost 2d. 



Gales. 39m., ist, W.N.W.; 36m., 2d, W.S.W.: 

 41m., 3d, S.S.W.; 48m., 4th, W.S.W.; 35m., 

 5th, N.W.: 40m., 9th, E.N.E.; 40m., 12th, 

 N.N.W.; 39m., 15th, W.N. W.; 52m., iSth, 

 S.: 47m., 19th. N.W.: 47m., 24th, S.S.W.; 

 40m.. 30th, N.W.; 45m., 31st, N.W. 



