Your log shows 6 knots, your GPS only 2,
but you could have done 10 knots over the ground.
That's what it means to have a tidal stream of 4 knots going with you in stead of against you.
Navionics Gold and Platinum charts has tidal data, and TIKI can show you the strength and direction of the current at any time.
On a Navionics chart you can click on different features, such as a light or buoy, and retrieve additional information. You can have a list of all the ports in the charts pop up, and jump to any port with a click.
Platinum charts even have port photos and pilot books.
This screen shot is from
TIKI Navionics Gold
