Nineteen full-scale hurricanes covering a period of 66 years are 

 used in this investigation. Hurricane Beulah (196T) is not included in 

 this analysis due to incomplete examination of the data available at this 

 time. Table 1 shows the peak surge heights (i.e., the highest water ele- 

 vation reached on the open coast) and hurricane parameters for all 19 

 storms. Some of the peak surges indicated in the Table were obtained 

 by transposition and adjustment of surge heights recorded in adjacent 

 estuaries and coastal streams. 



3. Surge Profile 



A hurricane that moves over the Continental Shelf and approaches the 

 coast piles up water at the shore over long reaches of the coastline. The 

 extent or breadth of the coast affected is dependent upon the hurricane 

 parameters involved and the basin characteristics. The peak open-coast 

 ,surge usually occiirs at the point of landfall of the region of maximum 

 winds (i.e., if the hurricane approaches normal or somewhat normal to 

 the coastline), and lesser surges are produced to the left and right of 

 the peak or maximum storm surge. In the development of frequencies for 

 hurricane surges for some specific position it is necessary to include 

 the peak surges as well as all lesser surges which occur at that location. 

 This simply means that surge profiles are required for all hurricanes 

 used in the surge frequency investigations. 



Although peak sirrge heights are known for the 19 hurricanes, only 

 limited information is available on the maximum water levels reached on 

 the coast adjacent to the peak surges, and this limited information is 

 based on observations of only the most recent storms. The most documented 

 storm in this respect is Hurricane Carla (1961), which provided the neces- 

 sary data for establishing a relationship of surge versus distance (pro- 

 file) along the Texas Coast. The surge profile for this storm revealed 

 that the maximum water levels to the right and to the left of the peak 

 surge varied, for all practical purposes, linearly with distance along 

 the coast. The slopes of the surge profile to the left and right of the 

 peak surge, however, were appreciably different, as could be expected 

 from the characteristics of a hurricane. 



Other storms with known surge heights to the left and right of the 

 peak surge were also used in deriving surge profiles. It was found that 

 the linear relationship was prevalent for all storms used, and the slopes 

 remained essentially constant with the vertical departure of the surge 

 height, dependent upon the magnitude of the peak surge elevation. Typical 

 s\irge-prof ile curves derived from this analysis are indicated in Figure 1. 

 The terms left and right in the figure, are directions as seen from the 

 sea. The typical surge profiles indicated on Figure 1 will not hold true 

 for hurricanes approaching and crossing the coast at small angles to the 

 coastline. For example. Hurricane Beulah (196T) approached and crossed 

 the shore near Brownsville, Texas, at an angle of approximately 15 degrees 

 from the coastline, and preliminary observations of water level elevations 

 indicate that a lesser surge occurred at the point of landfall of the 

 region of maximum winds than to the left and right of this position. 



