Interactions between Florida Bay and Atlantic Shelf Waters in Response to Tropical Storm Gordon

Wind, bottom pressure and current meter data are used to describe water level differences and exchanges between Florida Bay and Atlantic shelf waters during the passage of Tropical Storm Gordon on 15 November 1994. The data indicate that winds associated with the approaching storm forced a 30 cm set-up of water levels over the inner shelf creating a shelf-to-bay pressure gradient. During that time, current meters in three tidal channels connecting eastern Florida Bay with the Atlantic recorded a nontidal inflow to the bay that averaged between 17 and 32 cm s-1for 2 days. This represents a 4–6-fold increase in the longterm flow through these channels. A maximum storm-induced inflow of 71 cm s-1was recorded in Long Key Channel. For comparison, the root-mean-square values for the predicted tidal currents in the channels range between 26 and 41 cm s-1. About a day after the storm had passed water levels peaked in Cotton Key Basin, a sub-basin of eastern Florida Bay, at almost 50 cm above the previous 2-month mean and the Atlantic-to-bay pressure gradient reversed. As a result. water exited by the bay through the channels at a rate ranging between -8 and -34 cm s-1for 2 days. A maximum nontidal outflow of -78 cm s-1was observed in Indian Key Channel. Results indicate that Gordon caused significant perturbations on the long-term flow that occurs between Florida Bay and adjacent shelf waters, and storm effects were apparent for about 5 days.