BULLETIN No. 292. 



APRIL, 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, 2'/j.^ ft. 

 Height of Wifid Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximum reduced to freezing, 3025,10th, 7A. 

 Minimum reduced to freezing, 29.19, ist, o A. 

 Reduced! maximum reading, 30.56, loth, 7 A.; 

 Reducedt minimum reading, 29.50, ist, o A. 



Mean semi-daily reduced, 30.020 



Monthly range i.o6 



*Air Temperature. In Degrees Fahr. 



Highest 84.5,25th, 2:30 P. 



Lowest, 22.5, Sth, 6 A. 



Mean hourly, 47-6 



Mean of means of max. and min., .... 48.0 



Mean sensible (wet bulb), 429 



Montiily range, 62.0 



Highest mean daily, 6;.9. 25th 



Lowest mean daily, 34.2,9th 



Mean maximum, 58-3 



Mean minimum, 37.6 



Mean daily range, 20.7 



Greatest daily range 38.0, 22d 



Least daily range 6-5i 13th 



Humidity. 



Mean dew point, 38.5 



Mean force of vapor 338 



Mean relative humidity 74-4 



Precipitation. In inches. 



fotal precipitation 3-3° 



Number of days on which .01 inch or more 



rain fell ' '4 



Total snow in inches trace 



* Temperature in ground shelter. 

 Reduced to freezing and sea-level. 



Wind. 



Total movement, 5659m. 



Greatest daily movement, .... 542ni., 2d 



Least daily movement, 32m., 12th 



Mean daily movement, 189 m 



Mean hourly velocity, 7.9 m 



Maximum pressure per square foot, 16.5 lbs. = 



58m. per hour, 1st, S P., W.N.W. 

 Maximum velocity for 5 minutes, 30 m. per 



hour, ist, 9 p., W.N.W. 

 Prevailing Direction, West Northwest. 



Summary. 



West 13 per cent. 



South Southwest 13 " 



North Northwest 10 " 



Northwest 10 " 



Northeast 10 " 



Other directions 44 " 



Weather. 



Mean cloudiness observed, .... 55 per cent 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 191 hrs. =48 per cent. 



Number of clear days, 8 



Number of fair days, 12 



Number of cloudy days, 10 



Bright Sunghine. 



Number of hours recorded, - . 211 hrs=52^. 



Rain, 3d, 4th, 5th, 6th, 7th, 9th, nth, 12th, 



13th, T6th, 19th, 23d, 25th, 28th, 29th. 



Snow, 6th, 7th, 9th. 



Frosts, 7th, loth, 22d. 



Thunder and Lightning, none. 



Gales, 35 or more miles per hour : 58 m, ist, 



W.N.W.; 40m, 2d, W.S.W.; 38m., 19th, W.; 



39m., 30th, N. 



