associated with a qua si-geos trophic tilt of water level across the 

 ports as well as a tilt from southeast to northwest across the Gulf. 

 The 6.5 day period oscillations coincide with the natural modes on 

 the west Florida shelf (Marmorino, 1982). The excitation of the out- 

 of -phase transport and associated quasi-geostrophic tilt mode in the 

 present model is due to out-of-phase wind forcing at the ports (as 

 CeUi be produced by the cyclonic circulation in those hurricanes which 

 traverse the Cayman Sea) . Observational evidence to confirm the 

 existence of the 6.5 day mode in the actual Gulf is lacking (e.g., 

 the Key West gauge records do not show clear evidence for the large 

 amplitude 6.5 day oscillations which the model simulations for 

 hurricane Allen or HUR5 produce). However, except for locations near 

 the ports, the water level variations associated with the 6.5 day 

 tilt mode are small (less than 0.1 m along the northern and western 

 coast of the Gulf). Hence the quasi-geostrophic tilt mode is 

 probably not important with respect to forerunners in the northern 

 and western parts of the Gulf. 



Close examination of the tjq time sequences for the long term 

 simulations for PATHl show that, in addition to the presence of the 

 Helmholtz mode, a period of about 3.4 days is also present. But 

 there is very little evidence of the 6.5 day tilt mode in tjq. The 

 3.4 day mode in fact shows up in the time history of the spatial mean 

 water level for the Cayman Sea. Some observational evidence for such 

 a mode of oscillation exists for the Gulf (Halper, 1984, Kelly, 1985, 

 Kirwan et al., 1984). The relative excitation of these modes during 

 the forcing stage by hurricanes depends upon the path, the storm 



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