WHOLE VOL. 



NORTH AMERICA 



337 



ALPENA, UNITED STATES 



Lat. 45°5' N. Long. 83°30' W. Hb ~ 609 ft. 



PRESSURE AT SEA LEVEL 



Means of K7''+19''), 90th meridian W. 



1,000 mb. + 



Mean 16.5 17.9 16.0 15.5 15.3 13.8 15.0 16.7 16.9 16.9 17.6 17.1 



16.3 



