Daily maximum and minimum air temperatures at 25 locations on the perimeter of the Great Lakes for the period 1897 to 1977 were used to generate long term daily air temperatures and freezing and thawing degree-days (FDD's and TDD's). In addition daily, weekly, and monthly FDD's and daily TDD's were calculated for the 81 summer and 80 winter seasons between 1897 and 1877. this report describes the computational procedure and presents graphs and tables resulting from this analysis. The complete analysis is too voluminous to present in hard copy, but is available on microfilm through World Data Center A, Institure of Arcic and Alpine research, University of Colorado at Boulder, Boulder Colorado 80309.

Daily maximum and minimum air temperatures at 25 locations on the perimeter of the Great Lakes for the period 1897 to 1977 were used to generate long term daily air temperatures and freezing and thawing degree-days (FDD's and TDD's). In addition daily, weekly, and monthly FDD's and daily TDD's were calculated for the 81 summer and 80 winter seasons between 1897 and 1877. this report describes the computational procedure and presents graphs and tables resulting from this analysis. The complete analysis is too voluminous to present in hard copy, but is available on microfilm through World Data Center A, Institure of Arcic and Alpine research, University of Colorado at Boulder, Boulder Colorado 80309.