I BOAT NY HARBOR - CURRENTS AND TIDES
Times of high tides and low tides vary by location in NY Harbor. For example, high tide at W. 79th Street Boat Basin is 25-30 minutes later than high tide at the Battery.
Differences between low and high tides water levels in the harbor are 3' to 8' depending on the moon, sun, recent rainfall and local wind conditions. The blue line shows the astronomical predicted water level. The red line shows the observed real-time water level. The green line shows the forecasted level.
You can subtract the green low tide level from the green high tide level. If the difference is 5.5' or more, expect strong currents. This graph can also be used to predict flooding at other locations, e.g., if the green level is over 8 feet, W. 79th St Boat Basin's C Dock is forecasted to be awash.
Currents lag the times of high tide and low tide in the Hudson River. For example, the current at W. 79th Street Boat Basin will switch from flood to ebb 2.0 to 3.0 hours after high tide and from ebb to flood 2.5 to 4.0 hours after low tide. You can shorten your passage from the Hudson to Long Island Sound by hours by riding the currents - depart from a location on the Hudson to ride the ebb current to arrive at the Battery 1.0 hour after low tide at the Battery and then ride the flood current up the East River and out on to Long Island Sound.
If a south wind exceeds 10 knots and the harbor current is ebbing, expect wave heights 2-3 times normal height and possible whitecaps. Ditto for a north wind with current flooding.