METEOROLOGICAL OBSERVATORY 



OF THE 



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, 2'/j.^ ft. 

 Height of Wind Instruments 72 ft. 



BULLETIN No. 2 12. 



AUGUST, 1906. 



MONTHLY SUMMARY. 



I'ressure. In inches. 



Maximum reduced to freezing, 30.10, 2d, lo A. 

 Minimum reduced to freezing, 29.3S, 27th, 3 p. 

 Reducedt maximum reading, 30.38, 2d, 10 a. 

 Reducedt minimum reading, 29.66, 27th, 3 p. 



Mean semi-daily reduced, 30.022 



Monthly range, 0.72 



*Air Temperature. In Degrees Fahr. 



Highest, go.5, 14th, 4? 



Lowest, 47.5, i6th, 6 A.: 25th. 6 a. 



Mean liourly, 70.5 



Mean of means of max. and min., .... 71.2 



Mean sensible (wet bulb), 65. 8 



Monthly range, 43-o 



Highest mean daily 77.8,23d 



Lowest mean daily, 62.6, 15th 



Mean maximum, 82.7 



Mean minimum, 59 



Mean daily range, 22.9 



Greatest daily range, 34.0, 17th 



Least daily range, 12.0, 3d 



Humidity . 



Mean dew point, 63.6 



Mean force of vapor, 726 



Mean relative humidity, 82.9 



Precipitation. In inches. 



Total precipitation, 6.42 



Number of days on which .01 inch or more 

 rain or melted snow fell 14 



• Temperature in ground shelter. 

 t Reduced to freezing and sea-level. 



Wind. 



Total movement, 3412 m. 



Greatest daily movement, .... 225 m., 23d 



Least daily movement, 47 m., 4th 



Mean daily movement, no m. 



Mean hourly velocity, 4.6 m. 



Maximum pressure per square foot, 4.5 lbs.= 

 30 m. per hour, 21st, 5 p., S. 



Maximum velocity for 5 minutes, 24 m. per 

 hour 27th, 10:30 A., S. 



Prevailing Direction, South, Southwast. 



Summary. 



South, 26 per cent. 



Southwest, 13 " " 



Northeast, 13 " " 



Other directions, 48 " " 



Weatlier. 



Mean cloudiness observed, .... 50 per cent. 



Total cloudiness recorded by the Sun Ther- 

 mometer, 163 hrs.=38 per cent. 



Numter of clear days, 11 



Number of fair days, 14 



Number of cloudy days, 6 



BrigJit Siitishine. 



Number of hours recorded, . . 266 hrs.=62# 



Rain, 3d, 4th, 5th, 6th. 8th, loth, nth, 20th, 

 21st, 23rd, 24th, 26th, 27th, 30th, 31st. 



GrtJe«, 35 miles or more per hour, none. 



Thunder and Jjightning, 4th, 5th, 6th, 

 8th, 21st, 22d, 27th, 30th. 



