METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE 



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



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

 Height of Wind Instruments 72 ft. 



BULLETIN No. 144. 



DECEMBER, 1900. 



MONTHLY SUMMARY. 



Pressure. In inches. 

 Maximum reduced to freezing, 30.19, 15th, lo A 

 Minimum reduced to freezing, 28.67, 4th, 12 p 

 Reducedt maximum reading, 30.5*, i5tIi,io A 

 Reduced! minimum reading, 28.98, 4tli, 12 p 



Mean tri-daily reduced, 30.026 



Monthly range ■ 1.53 



*Air Temperature. In Degrees Fahr. 



Highest 58.0, 24th, 3 p. 



Lowest, 0.5, i8th, 7:30 a. 



Mean hourly, 30.6 



Mean of means of ma.x. and mm., .... 28.4 



Mean sensible (wet bulb), 26.9 



Monthly range, 57.5 



Highest mean daily 47.7, 24th 



Lowest mean daily 14.3, i;th 



Mean maximum, 37.4 



Mean minimum, 19.5 



Mean daily range, 17.9 



Greatest daily range, 32.5, i8th 



Least daily range, 8.5, 31st 



Muiniditi/. 



-Mean dew point, 21.7 



Mean force of vapor, 174 



Mean relative humidity, 74.9 



Precipitation. In inches. 



Total precipitation, . ■ 2.40 



Xumber of days on which .01 inch or more 

 rain or melted snow fell, ....... 7 



Snow, Total in inches, 3.0 



.Snow on ground at end of month, . . Trace 

 * Temperature in ground shelter. 

 t Reduced to freezing and sea-level. 



Wind. 



Total movement, 4203m. 



Greatest daily movement, ■ • • • 315 m., 14th 



Least daily movement 9 m., ist 



Mean daily movement 135-6 ni. 



Mean hourly velocity, 5.6 m. 



Maximum pressure per square foot, 13 lbs.= 



51 m. per hour, 9th, 10:30 A., S.S.W. 

 Prevailing Direction, Southwest. 

 Summary. 



South, 10 per cent. 



Southwest, 19 " " 



West, Southwest 10 " " 



West, . • 16 " " 



South, 10 " " 



Other directions, 35 " " 



Weatfier. 

 Mean cloudiness observed, .... 62 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 175.0 hrs. =62 percent. 



Number of clear days, 5 



Number of fair days, 10 



Number of cloudy days, 16 



Bright Sunshine. 

 Number of hours recorded, . . 108.0 hrs.=38H 

 Rain, 1st, 4th, 5th, 23d, 24th, 30th, 31st. 



Sleet, 30th. 

 Snow, 5th, 9th, nth, 13th, i6th. 25th, 26th 



2Sth. 



Gales, 3; miles or more per hour, 39m., 4th, 

 E.S.E.: 51m., 9th, S.S.W.; 46m., 13th, 

 W.N.W.; 35m., 14th, W.N.W.; 36m., 

 26th, N.W. 



