BULLETIN No. 245. 



MAY. I 909. 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, 5^ ft- Above sea level, 2yj.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



I'ressure, In inches. 



Maximum reduced to freezing, 29.99, 2ist, 6 A. 

 Minimum reduced to freezing, 29.17,1st, 3p. 

 Reducedt maximum reading, 30.29, 21st, G A. 

 Reducedt minimum reading, . 29.47, ist, 3 p. 



Mean semi-daily reduced, ■ 29.938 



Monthly range, 0.S2 



*Air Temperature. In Degrees Fahr. 



Highest, Si. 5, 15th, 4 p. 



Lowest, 320.3d, 5 A 



Mean hourly, 55-5 



Mean of means of max. and min 55.7 



Mean sensible (wet bulb), 49-9 



Monthly range, 49-° 



Highest mean daily, 6S.5, 15th 



Lowest mean daily, 38.5, ist 



Mean maximum, 67.1 



Mean minimum, 44.4 



Mean daily range 22.7 



Greatest daily range, 39-o, iSt'i, 3ist 



Least daily range, S.o, ist 



Huiniditj/. 



Mean dew point 45-i 



Mean force of vapor, 448 



Mean relative humidity, 712 



Precipitation. In inches. 



Total precipitation, 3.36 



Number of days on which .01 inch or more 

 rain or melted snow fell, -16 



• Temperature in ground shelter. 

 t Reduced to freezing and sea-level. 



lyind. 



total movement, 5371m. 



Greatest daily movement, . . . 362ni., loth. 



Least daily movement, 62m., 28th. 



Mean daily movement, i73ni. 



Mean hourly velocity, 7.2 ni. 



Maxinmm pressure per square foot, 8.0 lbs.= 



40m. per hour, 2d, 4P., WNW. 

 Maximum velocity for 5 minutes, 32ni. per 



hour 2d, 4 P., WNW. 

 Prevaihng Direction, North Northwest. 

 Summary. 



West Southwest 16 percent. 



North Northwest 13 " " 



North 13 " " 



North Northeast 10 " " 



Northeast 10 " " 



East Southeast 10 " " 



West Northwest 10 " " 



Other directions, 18 " " 



Weather. 

 Mean' cloudiness observed, . ■ . .56percent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, . ... i9ohrs.= 42per cent. 



Number of clear days 13 



Number of fair days n 



Number of cloudy days, 7 



Brifffit Siitishine. 

 Number of hours recorded, . . 263 hrs. = 58^ 

 Kain, ist, 3d, 4th, 5th, 6th, 7th, 9th, loth, 



nth. 14th, i6th, 17th, iSth, 19th, 22d, 23d, 



24th, 27th, 28th, 29th. 

 Light Frost, 12th. 

 Thiindei- and Lightning, 6th, 7th, loth, 



14th, 27th, 28th, 29th. 

 Hail, 5th. 

 Gales, 35 miles or more per honr ; 40m. 



2d, W.N.W.; 37m. loth, W.S.W.; 35m. 



30th, N.N.E. 



