TIDAL CURVE

Avonmouth is a Standard Port for the Bristol Channel and the tidal curve below is a very useful tool for finding out the height of tide for a given time for various secondary Ports. When anchoring off shore or entering harbours this will assist you in calculating the tidal heights. Using the tidal curve and filling in the LW Ht and Hw Ht plus the LW and HW times for a given day it is possible to find the height of tide. You will notice two different curves, one in red for Springs and one in Blue for Neaps. The following secondary Ports use Avonmouth as the Standard Port, PORTISHEAD, CLEVEDON, WESTON SUPER MARE, BURNHAM-ON-SEA, BRIDGWATER, WATCHET. Please see almanac for full list of Secondary Ports

If going further down the Bristol Channel the required Standard Port is Milford Haven. The following secondary Ports use Milford Haven as the Standard Port, SWANSEA, MUMBLES, PORT TALBOT, PORTHCAWL, CARMARTHEN, FERRYSIDE, LLANELLI, BURRY PORT, STACKPOLE QUAY, TENBY, DALE ROADS, NEYLAND, ILFRACOMBE, LUNDY, APPLEDORE, BIDEFORD, CLOVELLY, PADSTOW, ST IVES. Please see almanac for full list of Secondary Ports

Using tidal data for your chosen SECONDARY PORT select appropriate Tidal Curve (e.g. Burnham on Sea uses Avonmouth)

A. Insert LW Ht and Insert HW Ht. Join the two points with a straight line. In this example 0m and 12m have been selected.

B. Insert First LW Time, HW Time and Second LW time in graph below. Fill in the boxes for HW+1, +2, +3 etc.

C Select required Time, draw vertical line until it intercepts red curve , if springs, draw horizontal line until it intercepts straight gradient line, and then draw vertical line until it intersects Tidal Heights Scale. Read Off Height, in this example 8.6m for a time of 10.00hrs.

D Download ZIP file, Excel Document, includes Tidal Curves for Milford Haven and Avonmouth, Print Preview, Page Set Up Select Landscape, Scaling select Fit to Page, Paper Size A4, OK, PRINT, for future reference.