One is always moving on the water — waves, swell, ebb, flood, rise and fall. Along the Georgia coast the last four set the rhythm of the day, the rhythm of one’s travel. We are fortunate to have NOAA to work out all the predictive dynamics for us.
However, nature provides a pretty effective source of real time information. These cues aren’t just fascinating, they’re useful.
First, there is the Rule of 12ths. On the East Coast, tides change just a bit over every six hours. So, roughly, in the first hour the tide changes by about 1/12 its total range. In the second and next to last hour 2/12. And in the third and second to last hour by 3/12 each. Here, where we have 9 foot tides, that would be 9 inches, 18 inches, 27 inches, 27 inches, 18 inches, 9 inches. The bars in the picture are scaled that way. In these Sounds and Rivers, if you only see dry golden grass and not many land birds it is high tide. When you can see all the green grass the tide is about 3/12 out (~2 hours). If you see about as much mud as green grass, 6/12. If there is about twice as much mud as green grass, it’s pretty much low tide. Enough for today, it’s too pretty out to sit and type.