Sketching a Synoptic Chart

At Coastal Skipper level you should be able to sketch a rough synoptic chart from the general synopsis portion of the shipping forecast. This gives you a spatial picture of where highs, lows, and fronts are — and where they are moving.

Start by placing the centres of any highs and lows mentioned in the synopsis (e.g., 'Low 995 mb, 57N 10W, moving NE slowly'). Then mark any fronts described. Draw a few isobars based on the pressure centres and the wind information given for each sea area. The wind direction tells you which way the isobars run; the wind strength tells you how closely spaced they are.

Even a rough sketch makes the forecast far more useful than listening without a visual reference. You can then track the chart against subsequent forecasts to build a picture of how the weather pattern is evolving.