CLIMATOLOGY OF WIND-DRIVEN RAIN FOR THE CONTIGUOUS UNITED STATES FOR THE PERIOD 1971 TO 1995

Abstract

Rainfall that is pushed along horizontally by the wind is referred to as wind-driven rain (WDR) or driving rain. Water penetration of exposed building surfaces is enhanced with WDR, and structural damage is accelerated with repeated WDR exposure. Additionally, WDR is an agent for enhanced soil erosion and for dispersal of certain plant diseases. This research provides a descriptive climatology of WDR for the contiguous United States. WDR intensity is estimated from a linear regression model that develops a relationship between rainfall on a horizontal surface and rainfall on a vertical surface. The WDR estimates are used to create maps of WDR intensity, WDR event duration, WDR annual frequency, WDR total receipt, and WDR direction. A 25–year period of record (POR) of hourly data is used for 182 stations across the United States. Areas of highest WDR intensity, duration, and frequency are found in the southern United States, especially along the Gulf Coast. Directional indices indicate that WDR occurs most often from easterly directions in locations in the southeast and central United States, while WDR is predominantly from the south along the West Coast. [Key words: wind-driven rain, rainfall, climatology, United States.]