BULLETIN No. 305. 



MAY, 1914 



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 fi- Above sea level, 2yj.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximum reduced to freezing, 30 20, i8th, 9 A. 

 Minimum reduced to freezing, 29.19, 6th, 4 A. 

 Reduced! maximum reading, 30.50, i8th, 9 A. 

 Reducedt minimum reading, 29.49, 6th, 4 A. 



Mean semi-daily reduced, 3o-043 



Monthly range i-oi 



*Air Temperature. In Degrees Fahr. 



Highest 9I.0. 27th, 2 p. 



Lowest 27.0, 2d, 5 A. 



Mean hourly, 59-° 



Mean of means of max. and min., .... 58.9 



Mean sensible (wet bulb), 57-5 



Monthly range, 64.0 



Highest mean daily, 75-9. 27th 



Lowest mean daily, 40-3i i3th 



Mean maximum, 72.3 



Mean minimum, 45-5 



Mean daily range, 26.7 



Greatest daily range 39.0, 3d, i8th 



Least daily range, 6-0, 13th 



Humidity. 



Mean dew point 49-3 



Mean force of vapor, 522 



Mean relative humidity, 74-5 



Precipitation. In inches. 



Total precipitation, 3-56 



Number of days on which .01 inch or more 



rainfell 



♦Temperature in ground shelter. 

 1 Keduoed to freezing and sea-level. 



Wind. 



Total movement, 4491m. 



Greatest daily movement 364m., 6th 



Least daily movement, ...... .42m.,i8th 



Mean daily movement, 145 m 



Mean hourly velocity, 6.0 m 



Maximum pressure per square foot, 19.0 lbs.= 



62m. per hour, 27th, 5P., W. 

 Maximum velocity for 5 minutes, 30m. per 



hour, 27th, 5P., W. 

 Prevailing Direction. West Northwest. 



Summary. 



North Northwest 26 per cent. 



Northeast 13 " 



West 13 ■' 



West Northwest 10 " 



Northwest 10 



Other directions 28 " 



Weatlier. 



Mean cloudiness observed, .... 42 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 129 hrs.=28 per cent. 



Number of clear days 15 



Number of fair days, 12 



Number of cloudy days, 4 



Briglit Sunslilne. 



Number of hours recorded, . . 324hrs=72*. 



Rain, 4th, 5th, 6th, 8th, 9th, nth, 12th, 13th, 



14th, 17th, 25th, 26th, 27th, 30th. 



Frosts, ist, 2d, i6th. 



Tliunder and Lightning, 4th, 9th, 12th, 



26th, 27th. 



Gales, 35 or more miles per hour : 37m, ist, 



N.W.;4om,2d, N.N.W.; 40m, 6th, N.N.W.: 



54m, 23d, N.W.; 38m, 25th, S.S.W.; 62m, 



27th, W. 



