BULLETIN No. 291. 



MARCH. 1913 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



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



Heii^kt of barometer above ground, ^i ft. Above sea level, 2'/j.^ ft. 

 Height of Wind Instruments 72 ft. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Vlaxununi reduced to freezing, 30 56, iSth, 8a.; 

 \Iiriiiniiin reduced to freezing, 28.96, 27th, 5 P. 

 Keducedt ma.\inuiui reading, 30.S8, 18th, 8 A.; 

 Keducedt minimum reading, 29.26, 27tii, 5 P. 



Mean semi-daily reduced, 30.112 



Montlily range 1.92 



*Air Temperature. In Degrees Falir. 



Higliest 74.0, 25th, 3:30 P. 



Lowest, I.e. 8tli, 3 A. 



.Mean hourly, 37.9 



Mean of means of max. and min 3S.3 



Mean sensible (wet bulb), 34 3 



Monthly range, 73 o 



Highest mean daily, 59 4. 25th 



Lowest mean daily 9-4. 7th 



.Mean maximum, 47-9 



Mean minimum . .... 28.5 



Mean daily range i9-4 



Greatest daily range, 3^-5- 9th 



Laist daily range, . 4.0, ist, 4th 



Humidity. 



Mean dew point, 30-7 



Mean force of vapor, . . 236 



Mean relative humidity, 79-3 



Precipitation. In inches. 



Total precipitation, 6 



Mumber of days on which .01 inch or more 



rain fell '17 



Total snow in inches 5-° 



*Temperature in ground shelter. 

 Reduced to freezing and sea-level. 



Wind. 



Total movement, 6413m. 



Greatest daily movement, .... 443ni., 22d 



Least daily movement 40m., ist, 20th 



Mean daily movement 207 m 



Mean hourly velocity, 8.6 m 



Maximum pressure per square foot, 23.5 lbs.= 



68m. per hour, 31st, 3 P., S.W. 

 Maximum velocity for 5 minutes, 48 ni. per 



hour, 27th, 9 p., \V. 

 Prevailing Direction, West Southwest. 



Summary. 



West 20 per cent, 



South Southwest 20 " 



South Southeast i3 " " 



South 10 " " 



West Southwest 10 " 



Northwest 10 



Other directions 17" 



Weather. 

 Mean cloudiness observed, . ■ . . 62 per cent, 

 rotal cloudiness recorded by the Sun Ther- 

 mometer, .... iS9hrs.= 5i per cent. 



Number of clear days 10 



Number of fair days, 8 



Number of cloudy days, i3 



Briglit Sunshine. 

 Number of hours recorded, . . 182 hrs=49^. 

 Rain, ist, 9th, loth, nth, 13th, I4th,l5th,i6th, 



20th, 21st. 23d, 24th, 25th, 26th, 27th, 30th, 31st. 

 "Jnow, 2d, 4th, 6th,"iith. 

 Thunder and Tig .tning, 1st, 25th, 26th, 



27th, 31st. 

 Days of Sleighing, 3. 



Gales, 35 or more miles per hour : 64 m, 20th, 

 W.N.W.; 44ni, 6th, W.N.W.; 49m, 7th, W.; 

 43m. 2ist, S.S.W.; 43m., 22d,W.;36m. 24th,S.; 

 48111. 27th, \V.; 39m. 28th, W.; 68ni. 31st, S.W. 

 Hail. 31st. 



