A Note on the Radius of Maximum Wind for Hurricanes

Abstract

Studies of wind waves in the shallow water require the input of deep water wave characteristics. Under hurricane conditions, a parameter called the radius of maximum wind, R, is needed for deep water wave generation. Although literature states that the typical value of R is either 40 or 50 km, it has not been quantified. This brief note is to provide the R values as a function of the Saffir/Simpson hurricane classification. On the basis of 59 hurricanes from 1893 through 1979 affecting the U.S. coastline as compiled by Simpson and Riehl, 90% fall between categories 2 and 4 having a composite mean R = 48 km with a standard deviation of only 3 km. Since only 8% and 2% sample remain for Categories 1 and 5, respectively, the statistical results are not recommended; however use of the generic formula to obtain R should be employed. The composite mean of 47 km for all hurricanes as compiled with central pressures between 909 and 993 mb is obtained, which quantifies the literature value.