3o8 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 90 



MAZATLAN, MEXICO 



Lat. 23° 11' N. Long. 106° 25' W. H = 78 m * 



PRESSURE AT SEA-LEVEL: COR. TO 0° C. (32° F.) AND TO 



GRAV. AT 45° LAT.f 



Means of £(7 h + 14 h + 21 1 '), 90th meridian W. 



700 mm + 



M'ns 61.2 61.1 60.3 59.6 58.8 58.0 59.3 59.0 57.4 58.0 60.0 60.8 59.4 



TEMPERATURE IN DEGREES C. 

 Means of V, 14", and 21" 



Date Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Means 



1921 

 1922 

 1923 

 1924 

 1925 



1926 

 1927 

 1928 

 1929 

 1930 



19.4 

 19.1 

 20.7 

 20.8 

 17.0 



19.7 

 19.4 

 20.7 

 19.2 



20.2 



18.4 

 18.9 

 18.5 

 20.8 

 19.4 



21.4 

 20.1 

 19.8 

 18.2 



20.2 



19.1 

 17.8 

 18.7 

 20.0 

 20.5 



21.1 

 18.6 

 21.1 

 18.0 

 20.0 



20.2 

 19.5 

 21.6 

 19.7 

 22.4 



21.7 

 20.2 

 21.5 

 21.2 



22.2 



22.8 

 23.9 

 24.6 

 22.9 

 24.9 



23.7 

 24.1 

 25.0 

 23.7 

 23.2 



26.2 

 26.8 

 26.6 

 25.8 

 25.8 



27.1 

 26.5 

 2.6.8 

 26.4 

 23.8 



2,6.7 

 27.9 

 27.7 

 27.4 



27.7 



27.8 

 27.5 

 27.4 

 27.3 

 27.7 



27.2 

 2.8.1 



27.7 

 27.7 



27.9 

 27.5 

 27.3 

 27.5 



28.2 



27.4 

 27.4 

 27.7 

 27.0 

 27.7 



27.1 

 26.7 

 27.5 

 27.8 

 28.6 



27.0 

 26.8 

 26.6 

 26.4 

 20.1 



26.7 

 26.0 

 27.2 

 25.9 

 26.0 



24.0 

 21.1 

 23.8 

 22.6 

 24.0 



23.4 

 24.0 

 24.1 

 22.2 

 23.6 



21.0 

 21.0 

 20.5 

 18.4 

 21.3 



20.0 

 21.0 

 20.3 

 21.3 

 21.4 



M'ns 19.6 19.6 19.5 21.0 23.9 26.2 27.5 27.8 27.5 26.5 23.3 20.6 



23.2 

 23.2 

 23.7 

 23.3 



23.8 



24.0 

 23.5 

 24.0 

 23.2 

 23.7 



23.6 



TOTAL PRECIPITATION IN MILLIMETERS 



* Height of station changed and pressure not reduced to that in vol. 79. 

 t A correction of — 1.4 m was applied for gravity. 



