Tide is not an issue at Jewfish Creek. Current is wind-driven in that area of the Upper Keys. The current can run one direction for days at a time and then go the opposite way for days at a time. No good way to predict which way it will be flowing at any given time.

If the wind is out of the east/south for days, the current through the bridge may continue to flow from east to west for a while, even if the wind switches to the west/north. And vice versa.