How do you calculate the tidal flow from one place to another: ie, Sabine Pass, Tx. to Orange, Tx.

Do you mean something like this -

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https://en.wikipedia.org/wiki/Tide-predicting_machine

I don't think there is any such calculation. There are just too many variables. One can predict the tides for any given location, but using that location to calculate the tide prediction for another location is just not possible.

However, locations close together are open to good guesstimations.

For example. A lake might be 45 minutes behind the beach which it opens on. But if it rains and the creeks fill the lake with more water than the tide can push back, then it might be 2 hours difference. But at the same time, one could estimate that on any normal day the tide difference will be 45 minutes, even though on some days it might be hours.

Too many variables for a set in concrete calculation...But that is fishing

Haha...I got an invalid image

The formula is in the Wiki article