METEOROLOGICAL OBSERVATORY 



Hatch Experiment Station, 



MASSACHUSETTS AGRICULTURAL COLLEGE 



Latitude, 42° 23' 1S.;V' N. Lon^iiUide, 72° 31' 10" W. 



Height of instruments above ground, 51 ft. Above sea level, 260 ft. 



BULLETIN No 41. 



MAY, 1892. 



mONTHLY SUmMARY. 



f'renxure. In inches. 

 Actual iiiaxiiiuiin reailing, . . 30.13, 1st, a. 

 Actual uiiiiinuiin reading, . . -id. 19, '27tli, 11 a. 



INIean reiluced to sea level, -29.943 



Monthly range, 94 



*Air Teinpvrntitve, In Degrees Fahr. 



Highest 82. ; S4. 



Lowest 3H.r); -28. 



Mean, .^5.1; .'j(j. 



Monthly liauge, 45.,5; .lU. 



nighest mean daily 70. (i; 71. .5 



Lowest mean daily, 41. .t; 40.3 



Mean maximum, 63. ; 65.3. 



Mean minimum, 49.1 ; 43.5 



Mean daily range 13.9; 21.7 



Greatest daily range, 27. ; 37. 



Least daily range, t ; 8.5 



Hiiiniiliti/. 



Mean dew point, 44.9 



Mean force of vapor, .'5407 



Mean relative luiniidity, 60.3 



Wind. 



Prevailing Directions. 



.South West, ... 17 percent. 



North 13 " 



South, .Southwest 13 " " 



North West, 12 " 



Other directions 45 " " 



Total movement, 50.56m. 



Greatest ilaily movement, . . . . 369 m., 8th. 



Least daily movement, 75 m., 2nd. 



Mean daily movement 163 m. 



Mean hourly velocity, 6.8 m. 



Maximum pressure per squai-e foot, 15311)s.= 

 .56 ni. per hour, 16th, at 3.30 P. 



* f'recij>itnliini. In inches. 

 Total precipitation, 4.73; 6.28 



yyenflier. 



Mean cloudiness observed, . . . 60 per cent. 



Number of clear days, 8 



Number of fair days, 9 



Number of cloudy <lays, 14 



Total cloudiness recorded by the Sun Ther- 

 mometer, . . . 280 hours or 61 per cent. 

 Number of days on which .01 inch or moi-e 

 rain or melted snow fell, ... .16 



Rrifflit Siiiishine. 



Numl)er of Hours recorded, 183 



Rain, 1st, 2d, 4th, .5th, 6th, llth, !2th, 13tli, 



14th, 1.5tl), 16th, 19th, 20th, 21st, 22d, 23d, 



2.5th, 27th, 29th, 30th. 



Aurora Sore<ills, ISth. 



Jtainbow 12th. 



Thunder and TAffhtnintf 3rd, 12tlr 



Frost, 1st, 8th, 10th. 



Mean Osont, .39 per cent. 



Hal OS. 



Solar, 1st, 4th, .5th, 17th, 26th. 



Coronae, 7th, 10th. 



Galoa, of .50 or more miles per hour, . .53, 7th , 

 N. W.; 50, 8th, N. N. E. ; .56, 16th, N. W. 



*The first figures denote readings at top of tower, the second at base. 



