BULLETIN No. 270. 



JUNE, I9M 



Meteorological Observations 



AT THIC 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above groiciid, 51 ft. Above sea level, ^73-5 .ft- 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Miixiinmn leduced to freezing, 29 94, 2;th, 6 A. 

 Minimiini reduced to freezing, 29.27, 14111,3:301'. 

 !<.ediicedl maximum reading, 30.24, 25th, 6 A. 

 Reducedt minimum reading,29.55, 14th, 3:30 v 



Mean semi-daily reduced, 29.936 



Monthly range 0.69 



*Air Temperature. In Degrees Fahr. 



Highest, S9.5, 2Sth, 3 p. 



Lowest, 44-5. 17th, 5 A. 



Mean hourly, 64.5 



Mean of means of max. and min., .... 64.4 



Mean sensible (wet bulb), 59-4 



Monthly range 45-o 



Highest mean daily, 76.3,28th 



Lowest mean daily, 56.0,. i3t!' 



Mean maximum 75-9 



Me.m minimum, S2.8 



Mean daily range 23.1 



Greatest daily range, 36-0. 9tli 



Least daily range 4-0- 7th 



Humidity. 



Mean dew point, 55-8 



Mean force of vapor 61S 



Mean relative humidity, 74-5 



Precipitation. In inches. 



Total precipitation, 2.0: 



Number of days on which .01 inch or more 



rain fell, ■ <i 



•Temperature in ground shelter. 

 t Keduced to freezing and sea-level. 



"Wind. 



Total movement 3546m 



Greatest daily movement, .... 284 m., ist 



Least daily movement 35ni., 25th 



Mean daily movement, 118.2 m 



Mean hourly velocity, 4-9 m 



Maximum pressure per square foot, 5.0 lbs.= 

 32m. per hour, 21st, 10 A., N.N.W. 



Maximum velocity for 5 minutes, 24m. per 



hour, 2d, 4 P., W.N.W. 

 Prevaihng Direction, North Northwest. 



Summary. 



North 20 percent. 



Northwest 17 " " 



North Northwest 13 " " 



West 13 " " 



North Northeast 10 " " 



Other directions 27 " " 



Weather. 



Mean cloudiness observed, .... 54 per cent. 



Total cloudiness recorded by the Sun Ther- 

 mometer, . . 177 hrs. =39 per cent. 



Number of clear days 9 



Number of fair days, ' 13 



Number of cloudy days, S 



Bright Sunshine. 



Number of hours recorded, . . 280 hrs. =61^ 

 Hain, ist, 3d, 5th, 6th, 7th, loth, nth, 

 12th, 13th, 14th, 20tli, 22d, 25th, 26th, 2Sth. 

 Tliunder ami Lightning, nth, 12th, 20th. 

 Gales, 35 or more miles per hour : None. 



