How To: Tidal Heights

When you first load the tidal heights page, you will see an interactive outline map of the RYA Territories, with Standard and Secondary Ports drawn over the top. The Standard Ports are always visible, however the secondary ports will be hidden when you are zoomed out, and appear when you are zoomed in. A dot on the base map indicates the presence of tidal data. 

The interactive map can be controlled using the 'Zoom' buttons top left, a mouse wheel, mouse clicks (click to zoom in, shift+click to zoom out), and pinch-to-zoom gestures. You can scroll by pressing your primary mouse key and moving the mouse/touch pad, and using a touch drag input. 

Selecting a Port

When you have found the port you are looking for, a click or tap will make some options appear on the right hand side of the map/immediately below the map (on smaller screens). These will explain the type of port you have selected, and the time zone used for the prediction. The name of the port and a basic picture of its location will also appear here. 

Selecting a Date

Clicking on 'Select Date' will produce an interactive calendar, with the month displayed at the top. Left (<) and Right (>) buttons will appear either side of the month so that you can move through the year. To select a date for the month displayed, simply click or tap on the number. 

Viewing the Tidal Graphs and Spot Heights

Once you have selected a date, the Almanac Data will appear in a table below the calendar, showing event times and heights. Below this, a curve will be drawn for your port, and below this you will find a scrollable table of spot heights and times. 

The circular 'nodes' or data points on the tidal curve can be clicked/tapped to produce a time and height. The spot height table can be dragged left to show later times that are off the screen. Please note that you may need to convert the times given to adjust for daylight saving time or into other time zones depending on the scenario you are working through. If in doubt, check with your instructor.

Selecting a new date will produce new data for the selected port. Selecting a new port will start the process again. 

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