BULLETIN No. 256. 



FEBRUARY, 1911 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGKICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, ji ft. Above sea level, 2yj.^ ft. 

 Height of Witui Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inclies. . 



Mrtxinmm reduced to freezing, 30.31, i6tli, S A. 

 Minimum reduced to freezing, 29.24, 4th, 2 p. 

 Keducedt maximum reading, 130.64, i6tli, 8 a. 

 Keducedt minimum reading, 29.55, 4th, 2 P. 



Mean semi-daily reduced, 30.116 



Monthly range, 1.09 



*Air Temperature. In Degrees Fahr. 



Highest 51.5, 25th, 2:30 P. 



I.owest, -3.0, i6th, 7:30 A. 



Mean hourly 23.3 



Mean of means of max. and min 22.8 



Mean sensible (wet bulb) 20.0 



Monthly range, 54-5 



Highest mean daily, 39.4,26th. 



Lowest mean daily, 5-S, 6th 



Mean maximum 3i-7 



Mean minimum i3-9 



Mean daily range, i7-8 



Greatest daily range 44-o, i6th 



[.east daily range 6-5. 20th 



Humidity. 



Mean dew point i5-3 



Mean force of vapor, 126 



Mean relative liumidity 77-6 



Precipitation. In inches. 



rot.\l precipitation, 2.1S 



Number of days on wliich .01 inch or more 



rain fell, ' ^ 



'I'otal snnw in inches 'O-^ 



Temperature in ground shelter. 

 Reduced to freezing and sea-level. 



Wind. 



Total movement, 55i5ni 



Greatest daily movement 464m., 23d 



Least daily movement, 14m., 9th 



Mean daily movement, 197 m 



Mean hourly velocity, 8.2 m 



Maximum pressure per square foot, 9.5 lbs.= 



44m. per hour, 5th, 10 A., W.N.W. 

 Maximum velocity for 5 minntes, 30m. per 



hour 27th, 10:30 P., W.N.W. 

 Prevailing Direction. West Northwest. 



Summary. 



West iS per cent. 



West Northwest 18 



North Northwest 14 



North 14 



South II 



Other directions 25 



Weather. 



Mean cloudiness observed, . • • • 55 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, i64hrs.=55 per cent. 



Number of clear days, 10 



Number of fair days, 5 



Number of cloudy days, 13 



liriffht Sunshine. 



Numlier of hours recorded, . . 132 hrs.=45< 



Rain, 2d, 4th, 17th. 



Snow 2d, 3d, 4th, 6th, 7th, Sth, 9th, nth, 



13th, 14th, iSth, 20th, 22d. 24th. 

 Days Sleighing, 22. 

 Gales, 35 or more miles per hour : 36m, 4th, 



W.N.W.; 44n), 5th, W.N.W.; 36m, 23d, 



W.S.W.; 36m, 27th, N.W. 



