2. Hypothetical storms 



The hypothetical storms were assumed to be characterized by the 

 NWS23 parametric model with time invariant radius of maximum wind, 

 translational speed and central pressure deficit. Three constant 

 forward speeds of 15, 25 and 35 km/h were adopted. The slowest one 

 was comparable to the average forward speed of hurricane Car la while 

 the fastest speed was approximately the translation speed of 

 hurricane Allen when it was in the Cayman Sea. 



Two radii of maximum wind, 30 and 60 km, were selected to 

 account for the scale variation of the atmospheric forcing. The 

 radii were kept constant for the entire simulation period. The range 

 of radius of maximum wind for Gulf Coast hurricanes of record as 

 summarized in Schwerdt et al. (1979) was approximately 10 to 60 km. 

 This range of radii applies to those storms making landfall between 

 Port Isabel and Apalachicola, which covered the landfall locations of 

 the five selected paths. The large radius is at the upper limit and 

 the other is about the average of the observed range. The 

 approximate dimensions of a grid block are 25 km x 27 km and, 

 therefore, sets a lower limit on the radius of maximum wind which can 

 be used. Storms with a radius of maximum wind smaller than the, grid 

 size would not be resolved and the associated wind field would be 

 highly distorted. 



The last characteristic considered was the pressure drop (AP 

 =p -p ) . It is known, however, that there is a nearly linear 

 relationship between the peak surge and the pressure deficit, other 

 parameters being held fixed (Jelesnianski, 1972). Therefore, a 



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