Normal Degree Days Above Any Base by the Universal Truncation Coefficient

Equations are developed for obtaining mean monthly degree days above any base from mean monthly temperature and standard deviation of monthly average temperature. By the use of data for all months for twelve widely scattered stations and four bases it is shown that the truncation coefficient for degree days below any base with proper modification of the argument also applies for degree days above any base. This is also proved analytically, which leads to some further aspects of the universality of the truncation coefficient. Two formulas for the coefficient are also developed.