Regional analysis of extreme gust wind speed

Abstract

There are two objectives of this study. The first objective is to determine the domain of attraction of an extreme value distribution of gust wind speeds, at a selected station, when only limited samples from the site are available. The second objective is to perform a series of homogeneity tests for the selected stations, such that homogenous regions for these extreme gust winds may be identified. After carefully examining the wind data available, it was decided that 133 out of more than 750 stations in the contiguous United States were selected for the study. These selected stations all have confirmed Exposure C environments, with at least 15 years of records. All wind speeds used in this study were adjusted to 10 meters above ground level. On the basis of a S-statistic method, the proper representations of extreme gust winds at the 133 selected weather stations in the contiguous United States are examined. The results indicate that the annual extreme gust wind speeds at 65 out of the 133 stations are Gumbel extreme value distributions (Type I), whereas the other 68 stations' extreme gust wind speeds are reverse Weibull (Type III), distributed. Nine homogeneous regions, for the annual extreme gust winds, were identified by applying a Type I based regional analysis. This analysis was applied to the 65 stations in the contiguous United States whose annual extreme gust winds are Type I distributed.