

<-. ijL>A, „ •> 'i; J.. 



BULLETIN No. 289. 



JANUARY, 1913 



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 ft. Above sea level, 2JJ.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure, In inches. 



Maximum reduced to freezing, 30 41, 13th, iiA.; 



14th, 10 A. 

 Minimum reduced to freezing, 28.25, 3d, 6 p. 

 Reduced! maximum reading, 30.73, 13th, 11 A.; 



14th, 10 A. 

 Reduced! minimum reading, 28.55, 3d, 6 P. 



Mean semi-daily reduced, 30.096 



Montlily range, 2.18 



♦Air Temperature, In Degrees Falir. 



Highest, 59-5. 3d, 2:30 p. 



Lowest, ii.o, 9th, 7:30 A. 



Mean hourly, 33-6 



Mean of means of max. and min 34.2 



Mean sensible (wet bulb), 30-2 



Monthly range, 4S.5 



Highest mean daily, 46.2, iStii 



Lowest mean daily, 16.8, 9th 



Mean maximum, 43-° 



Mean minimum .... 25.3 



Mean daily range i7-7 



Greatest daily range, 35-5, 12th 



Least daily range, 7-o, 4th 



Humidity. 



Mean dew point, 25.9 



Mean force of vapor, 192 



Mean relative humidity, 79-0 



Precipitation. In inches. 



Total precipitation, 3-' 



Number of days on which .01 inch or more 



rain fell, ' '5 



Total snow in inches 4-° 



•Temperature in ground shelter. 

 Reduced to freezing and sea-level. 



Wind, 



Total movement, 5359m. 



Greatest daily movement, .... 642m., 4th 



Least daily movement, 14m., 2d 



Mean daily movement, 172 m 



Mean hourly velocity, 7.2 m 



Maximum pressure per square foot, 18.0 lbs. = 



60m. per hour, 3d, 3 p., S.W. 

 Maximum velocity for 5 minutes, 48 m. per 



hour, 3d, 3 P., S.W. 

 Prevailing Direction, Southwest. 

 Summary. 



West Northwest 13 Per cent 



South 10 " " 



South Southwest 13" 



Southwest 23 " 



South Southeast ......... 10 " 



Other directions 3' " 



Weather, 



Mean cloudiness observed, .... 63 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 115 hrs. =39 per cent. 



Number of clear days, 13 



Number of fair days, 10 



Number of cloudy days, 8 



Bright Sunshine. 



Number of hours recorded, . . 179 hrs=6i#. 



Rain, 2d, 3d, 5th, fbth, 7th, '8th, nth, 12th, 



15th, i6th, 17th, iSth, 2ist, 23d, 27th, 31st. 



Snow, 4th, 7th, 23d, 29th. 



Hail, 6th, 15th, iSth. 



Thunder and Lightning, i8th, 31st. 



Days of Sleighing, none. 



Gales, 35 or more miles per hour : 60 m, 3d, 



S.W.; 54m , 4th, S.W.; 37m., Sth, W.N.W.; 



49 m., i2th, W., 58m.,i8th, W.S.W.; 36 m., 



2ist, W.; 39 m.. 31st, S.S.W. 



