BULLETIN No. 405. 



SEPTEMBER. 1922 



Meteorological Observations 



AT THE 



MASSACHUSETTS 



AGllICULTURAL EXPERIMENT 



STATION. 



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



Height of barometer above ground, jr ft. Above sea level, 2jj.^ ft. 

 Height oj Wifiii Instruments y 2 ft. Time used, j^thMer. 



MONTHLY SUMMARY. 



Pressure. In inches. 



Maximum reduced to freezing, 30.15, 26th, 8 A 

 Minimum reduced to freezing, 29.38, 24tli, 7 p 

 Red\iced maximum reading 30.46, 26th, 8 a 

 Reduced minimum reading, 29.67, 26th, 7 p 



Mean semi-daily reduced 30.114 



Monthly range 0.79 



Air Temperature. In Degrees Fahr. 



Highest 86.5, 5th, 4:30 p 



Lowest 30.0,26th, 7 A 



Mean hourly 62.8 



Mean of means of max. and min 64.0 



Mean sensible (wet bulb) 57.3 



Monthly range 56.5 



Highest mean daily 73.1, 10th 



Lowest mean daily 47.3, 26th 



Mean maximum 75.9 



Mean minimum 52.1 



Mean daily range 23.8 



Greatest daily range 39.5, 23d 



Least daily range 11. 5, 7th 



Hnoiidity. 



Mean dew point 54. S 



Mean force of vapor 539 



Mean relative humidity 83.4 



Precipitaiion. In inches. 



Total precipitation, in inches 2.27 



Number of days on which .01 inch or more 

 rain fell S 



•Temperature in ground shelter. 

 "Reduced to freezing and sea-level. 



Wind. 



Total movement 2775 m 



Greatest daily movement 194m, 25th 



Least daily movement 26m, 5th 



Mean daily movement g2m 



Mean hourly velocity 3.9m 



Maximum pressure per square foot, 4.5 lbs = 



30m per hour, 15th, 8 p, S. 

 Maximum velocity for 5 minutes, 24 m per 



hour, 15th, 7 p., S. 

 Prevailing direction, Southwest. 



Summary. 



South Southwest 30 per cent 



Southwest 17 " " 



South 10 " " 



North Northeast 10 " '" 



Other directions 33 " " 



Weather. 



Mean cloudiness observed .... 41 per cent 

 Total cloudiness recorded by the Sun 



Thermometer . . 142 hours = 38 per cent. 



Number of clear days 10 



Number of fair days 12 



Number of cloudy days 8 



Bri{>ht Sunshine. 



Number hours recorded, 231 = 62 per cent. 

 Kain, 3d, 4th, 6th, I2tli, 14th, 15th, 20th, 



24th. 

 Frosts. First, J9th. 

 Frosts, Killing, 26tli. 



Thunder and Li^htninii, 3d, 4th, 6th, 12th, 

 I 14th, ijtli, 24th. 



Gales, none. 



