[rcassano]

After reading all the posts above and understanding the pros and cons of tide extrapolation I can say that I find the tide arrows for Long Island Sound, as displayed in "Coastal Explorer" , a great help in deciding if sailing down the middle of the Sound is an advantage or heading over to the shore is a boost. This art of extrapolation is just a guide and nothing more. Sometimes it is dead on accurate and others not so helpful. In any case, as long as you are keeping a good watch, tide arrows on the electronic chart should only be viewed as a possible aide not a hard set law one can sue on. Just like the disclaimer at the beginning of every GPS startup there should be one for tide prediction and extrapolation.