Design Gust Wind Speeds in the United States

Abstract

Analysis of gust winds in the United States has resulted in a new wind speed map for design-level winds. The map is based on 50-year peak gust speeds rather than fastest mile speeds used in the national wind load standard ANSI/ASCE 7-93. The change in gust duration is necessary because the fastest mile wind record has ended. A new technique was used to reduce variability due to sampling error in non-hurricane areas. Individual stations were demonstrated to be statistically independent and were combined as regional superstations. The purpose was to decrease sampling error by effectively increasing sample length. Wind speeds on the hurricane coast were converted from fastest mile to peak gust using new information on gusts in hurricanes. In addition, three Monte Carlo studies of hurricane speeds were considered in place of the one study available for the earlier map. Wind speeds for various return periods are presented.