BULLETIN No. 385. 



JANUARY, 192 1 



Meteorological Observations 



AT THK 



MASSACHUSETTS 



AGRICULTUIUL EXPEKIMENT 



STATION. 



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



Height of barometer above ground, jr ft. Above sea level, ^yj.j ft. 

 Height oj Wind Instruments y 2 ft. Time used, y^th Mer. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.56, 19th, 10 A 

 Minimum reduced to freezing, 29.10, 15th, i a 

 Reduced maximum reading . 30.90, agih, loA 

 Reduced minimum reading, 29.40, 15th, i a 



Mean semi-daily reduced 30.111 



Monthly range 1.50 



*Air Temperature. In Degrees Fahr. 



Highest 50.0, 2d, 3 p 



Lowest -6.0, 19th, 7 A 



Mean hourly 26.6 



Mean of means of max. and min 26.8 



Mean sensible (wet bulb) 22.5 



Monthly range 56.0 



Highest mean daily 43.6, 20 



Lowest mean daily 4.0, igth 



Mean maximum 36.8 



Mean minimum 16.7 



Mean daily range 20.1 



Greatest daily range 35.5,20th 



Least daily range 5.0, 30th 



HnmldKy. 



Mean dew point 16.6 



Mean force of vapor 147 



Mean relative humidity 72.2 



Precipitation. In inches. 



Total precipitation, in inches 2.( 



'i'otal snow, in inches 



Number of days on which .01 inch or more 



rain fell 



Days of Sleighing, 5 

 •Temperature in ground shelter. 

 "Reduced to freezing and sea-level. 



wiua. 



Total movement 5616 m 



Greatest daily movement 465m, 25th 



Least daily movement 41111 1st 



Mean daily movement 181 m 



Mean hourly velocity 7-5 m 



Maximum pressure per square foot, lo.o lbs = 



45m per hour, 17th, 12M, W.N.W. 

 Maximum velocity for 5 minutes, 30m ijer 



hour, 17th, 9 A, W.N.W. 

 Prevailing direction. West. 



Summary. 



North Northwest I. . . 13 per cent. 



West Northwest 13 " " 



South Southwest 26 "' " 



Northwest 13 " " 



West 16 " " 



Other directions 19 " " 



Weather. 



Mean cloudiness observed .... 42 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 127 hours = 43 per cent. 



Number of clear days 10 



Number of fair days 11 



Number of cloudy days 10 



Bright Sunshine. 



Number hours recorded, 167 hrs, = 57 per cent. 

 Rain. 1st, 2d, 5th. 7th, 14th, 21st, 23d, 



30th, 31st. 

 Snow, 7th, 14th, I7t!i, 2oth. 30th, 31st. 

 Gales, 45m. 17th, W.N.W.; 43ni, iSth, N.W. 



36m, 23d, W.X.W., 37ni, 24tli. N,\\ . 



