maps and statistical wind records on land, assuming that the winds blow toward 

 shore for a significant duration over a long, straight-line fetch. Once the 

 wind field is determined, storm surge may be estimated by using a storm surge 

 model. 



(4) Storm Surge in Enclosed Basins . An example of an inclined water 

 surface caused by wind shear stresses over an enclosed body of water occurred 

 during passage of the hurricane of 26-27 August 1949 over the northern part of 

 Lake Okeechobee, Florida. After the lake level was inclined by the wind, the 

 wind direction shifted 180 within 3 hours, resulting in a turning of the 

 height contours of the lake surface. However, the turning of the contours 

 lagged behind the wind so that for a time the wind blew parallel to the water 

 contours instead of perpendicular to them. Contour lines of the lake surface 

 from 1800 hours on 26 August to 0600 hours on 27 August 1949 are shown in 

 Figure 3-58 . The map contours for 2300 hours on 26 August show the wind 

 blowing parallel to the highest contours at two locations (Haurwitz, 1951; 

 Saville, 1952; Sibul, 1955; Tickner, 1957; U.S. Army Engineer District, 

 Jacksonville, 1955). 



Recorded examples of wind setup on the Great Lakes are available from the 

 U.S. Lake Survey, National Ocean Service, and NOAA. These observations have 

 been used for the development of theoretical methods for forecasting water 

 levels during approaching storms and for the planning and design of engineer- 

 ing works. As a result of the need to predict unusually high stages on the 

 Great Lakes, numerous theoretical investigations have been made of setup for 

 that area (Harris, 1953; Harris and Angelo, 1962; Platzman and Eao, 1963; 

 Jelesnianski, 1958; Irish and Platzman 1962; Platzman, 1958, 1963, 1967). 



Selection of hurricane parameters and the methods used for developing 

 overwater windspeeds and directions for various coastal zones of the United 

 States are discussed in detail by the National Weather Service (1979). The 

 basic design storm data should be carefully determined, since errors may 

 significantly affect the final results. 



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