BULLETIN No. 352. 



APRIL, 19 18 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



ffel^/ii of barometer above ground, 51 ft. Above sea level, ^73-5 f^- 

 Height oj Wind Instrninents 72 ft. 



MONTHLY SUMMARY. 



Pressuie. In inches. 

 Maximum reduced to freezing, 30.24, 7th, 9A 

 Minimum reduced to freezing, 29.29, 22d, 5 a 

 Reduced ma.ximum reading . . 30.55, 7th, 9A 

 Reducedt minimum reading, . 29.59, 22d, 5 A 



Mean semi-daily reduced 30.071 



Monthly range 0.96 



*Air Temperature. In Degrees Fahr. 



Highest 79 5, 30th, 3 p 



Lowest 24.0, 6th, 6:30 .\ 



Mean hourly 45.7 



Mean of means of max. and min 46.2 



Mean sensible (wet bulb) 40.1 



Monthly range 55.5 



Highest mean daily 62.4, 30th 



Lowest mean daily 31.7,11th 



Mean maximum 58.5 



Mean minimum 33.9 



Mean daily range 24.6 



Greatest daily range 44.5, 15th 



Least daily range 7.0,12th 



Humidity. 



Mean dew point 33.6 



Mean force of vapor 304 



Mean relative humidity 69.2 



Precipitation. In inches. 



Total precipitation, in inches 2.78 



Total snow, in inches 42 



Number of days on which .01 inch or more 



rain fell 13 



•Temperature in ground shelter. 

 ••Reduced to freezing and sea-level. 



Wind. 



Total movement 4544 m 



Greatest daily movement 341m, 24th 



Least daily movement 46m, 17th 



Mean daily movement 151 m 



Mean hourly velocity 6.3 m 



Maximum pressure per square foot, 7.5 lbs = 



39m per hour, 24th, 12 m, W.N.VV. 

 Ma.ximum velocity for 5 minutes, 29m per 



hour, 24th, 12 M, W.N.W. 

 Prevailing direction. Northwest. 



Summary. 



North 23 per cent 



South Southwest 10 " 



North Northeast 10 " " 



West Northwest 10 " " 



West 10 " " 



North Northwest 10 " " 



Other directions 27 " " 



Weather. 



Mean cloudiness observed .... ^2 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 167 hours = 42 per cent 



Number of clear days 10 



Number of fair days 13 



Number of cloudy days 7 



Bright Sunshine. 



Number hours recorded, 235 hrs, = 58 per cent 

 Rain. 3d, 8th, 9th, nth, 12th, 13th, 17th, iSth, 



19th, 2ist, 22d, 23d, 29th, 30th. 

 Snow, nth, 12th, 13th. 

 Hail, iSth. 



Thunder and Lightning, I7tii, 23d. 

 Frosts. 5th, 6th, 7th, 14th, 15th, 20th, 25th, 



26th. 

 Gales. 35 miles or more per hour : 39m. 



24tli, W.N.W. 



