METEOROLOGICAL OBSERVATORY 



Ilatcli Expcriiiieiit Station 



MASSACHUSETTS AGRICULTURAL COLLEGE, 



.A.iva:i€:EK,ST- 



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



Height of barometer above ground, 31 ft. Abo7'e sea lei^el, 2YJ.3 ft. 

 Height of Wind Instruments 72 ft. 



BULLETIN No. 124. 



APRIL, 1899. 



MONTHLY SUMMARY. 



fressure. In inches. 

 Maximum reduced to freezing, . 30.08, 6th, 7 A. 

 Minimum reduced to freezing-, 29.19, 8th, 4P. 

 Keducedt maximum reading, . 30.^9, 6th, 7 A. 

 Reducedt minimum reading, . 29.49, 8th, 4 p- 



Mean tri-daily reduced, 30.043 



Monthly range • 90 



*Air Temperature. In Degrees Fahr. 



Highest, S2.0, 30th, 2-30 P. 



Lowest 21.0, 3d, 6 A. 



Mean hourly, 46. j 



Mean of means of max. and nun., . . . .45.8 



Mean sensible (wet bulb), 42.4 



Monthly range, 61.0 



Highest mean daily 61.2,30th 



Lowest mean daily, 30.8, 2d 



Mean maximum, 5S.8 



Mean minimum, 32.7 



Mean daily range, 26.1 



Greatest daily range, 47.0, 29th 



Least daily range, 9-5, 2d 



Iliituiilitj/. 



Mean dew point, 36.5 



Mean force of vapor, 362 



Mean relative humidity, . . . • ... .69.2 

 Precipitation. In inches. 



Total precipitation, . • 1.79 



Number of days on wliich .01 inch or more 



rain or melted snow fell S 



Snow total in inches, i 



^%''ind. 

 Total movement, 3984 m. 



* Temperature in ground shelter, 

 t Reduced to freezing and sea-level. 



Greatest daily movement, .... 251 m., 17th 



Least daily movement, 51 m., 22d 



Mean daily movement, 132.8 m. 



Mean hourly velocity, 5.5 



Maximum pressure per square foot, 9.5 lbs.= 



44 m. per hour, on 17th, 5 P., N. W. 

 Prevailing Direction, West. 



Summary. 



Northwest, 27 per cent. 



North, 10 " " 



West 13 " " 



South 13 " " 



East Southeast, 10 " " 



South .Southwest, 10 " •' 



Other directions, 17 " " 



WeatJter. 

 Mean cloudiness observed, .... 42 per cent. 

 Total cloudiness recorded by the Sun Ther- 

 mometer, 121 hrs. =30 per cent. 



Number of clear days, 17 



Number of fair days, 10 



Number of cloudy days, 3 



liright Smishine. 

 Number of hours recorded, . . . 280 hrs. = 7o?S 



Rain, 2d, 7th, Sth, 12th, 14th, i6th, 20th, 21st, 

 25th, 26th. 



Snow, i6th. 



I/ast Frost) 22d. 



Thunder and Liyhtuiny, 14th, 25th. 



Gales, 35 miles or more per hour, 39 m., ist, 

 N.W. ; 43 m., 2d, N. W.; 3; m., 5th, N. ; 42 

 m., 9th, N.W.; 44 m., 17th, N. W. 



