Feasibility of Tide prediction

Hi guys,

I have seen some tide clocks and predictions here but I am looking to make a slightly different model. I am wanting to be able to input the predictions for a year and have the arduino programmed so that it can display whether the next tide is high or low, at what time and height.

This would need the arduino to be able to compare the current time with the next forecast, isolate this data from the rest and send it to the display.

I am sure this would be relatively straightforward, it would be my first project and want to use it at my lifeboat station.



Not sure what your actual question is? Are you looking for assistance in coding?

I also work with tide in a current project.
Predictions are available for my location (based on moon-fase), but the actual height will differ a lot from the year-predictions. More accurate predictions are ony a few days ahead and changing weather conditions will influence my location a lot (mainly wind force and direction).

I presume you have no available internet connection at the station? (since you want to input a year long prediction)

In my case, I can use this rather inaccurate data, because I only need to know at what part of the tide fase we are in, not the true height. I wonder how ‘true’ you expect your data to be.

Anyway, maybe you can specify a bit more on what you are after with your post?


putting in the tides from a table for the next year should be just up-loading data. same for moon phases.

you should be able to show moon and time as a prediction of a spring tide, but that seems to be about all you can do.

weather that is over the horizon will effect what you have on the beach.

by all means an UNO, a Real Time Clock and probably an SD card shield. maybe an SD/RTC shield ? what are you looking for regarding the display ?

Thanks guys,

I wanted to see if people thought it was possible before I started on it this summer.

The real height is really not relevant, the long term prediction is good enough as we always ere on the side of caution with them anyway. Something like your phase prediction is probably good enough (ie rising or falling and the time slack water occurs at would be sufficient).

We do have internet with Wifi coverage throughout the station but I think the easiest solution is to have the data pre programmed at the start of the year.

The display would be a simple LCD type. I want the device to sit on the boat so crew can read it before launch (it would be removed from the boat prior to launch like the display screen covers.

the time slack water occurs at would be sufficient

The real question is, how accurately do you need to know that time?

Tide calculations depend on a very large number of factors, and accurate times are very, very difficult to predict. Moon phase calculations can be off by an hour or more.

Our standard is to use the harbour trusts documented predictions.

If you can get those predictions in electronic text form, the easiest way to go would be to copy them on an SD card and have the Arduino with an SD shield display the appropriate prediction on each day.

That is a lot of work, considering that tide table booklets don't take up much pocket space.

Calculation to that accuracy by the Arduino is probably not possible.

I suppose the "crew" has a navigation computer. I'll be supprised if that hasn't got a "tide" and a "current" button.

Try "open CPN" (freeware). Add the c-map charts to that (kickass). All the charts and tides of the world...

"harmonic" (tide) files are inbuild. Maybe you can extract the part for your area.

Download GRIB files before you go out, and you will also have weather predictions on your chart. Leo..

I've used this library before, maybe it would be suitable?


Impressive! He got a portion of XTide running on an Arduino. However, the implementation calculates only the tide height for a single given time.

A bit of a pain to assemble the data for the location of interest. In the long run, I found it easier to carry the tide table booklet.

just use an arduino yun, it can go on the internet and look the info in real time

I understand (the library using Xtide) library to calculate the tide for a Single Place, not a single time, no?

not a single time, no?

One run of the program calculates the tide height for a given place, for a given time of day.

If you want to use it to calculate the times of slack tides, you have to run the program for a series of times during the day and determine when the tide is neither rising nor falling.