computed water level at St. Petersburg is higher than the recorded 

 throughout the period. This might be due to the fact that this tide 

 gauge station is located inland and not on the open coast. The 

 departure of the two hydrographs at Grand Isle is probably the result 

 of resuming the 20 inflow angle which shifted the wind direction 

 from the alongshore or slightly onshore to slightly offshore. The 

 comparison for Galveston is better than that obtained by Miyasaki 

 (1963), presumably because of the special care to match the observed 

 wind fields for the northwest Gulf Coast. At Port Isabel, the 

 discrepancy, which resembles that at Grand Isle but with a larger 

 deviation, is possibly due to the difference in locations of the tide 

 gauge station and the point where the computed water level was 

 sampled. The actual site of the tide gauge station is inside a semi- 

 enclosed embayment, as shown in Fig. 29. As a result, the effect of 

 the offshore component of the wind, which prevailed at this station 

 from approximately 0000 GMT 10 September onward, is limited while the 

 southerly component produces a set up within the constricted lagoon 

 at the gauge site. On the contrary, the computed hydrograph, sampled 

 at half the grid size away from the digitized coastline, is subjected 

 fully to the wind draw-down. Miyasaki (1963) obtained a similar 

 result at this station. 



Despite these discrepancies, the primary interest is the 

 comparison at Galveston where the largest surge, among all sampled 

 stations, occurs. It should be pointed out that the maximum computed 

 water level is not at Galveston but at the grid point (8,42), located 

 one grid block northeast of the path of Carla at the coast close to 



71 



