Three Anchor Bay Webcam and Live Wind
Windguru weather forecast
Reading Windguru for Three Anchor Bay
Three Anchor Bay has a very specific micro-climate based on the protection that Table Mountain offers from the prevailing South Easterly wind. In a pure moderate to strong South Easter, the wind shadow extends from the Green Point lighthouse to Clifton ridge. However, as the wind speed increases the wind shadow shrinks towards Three Anchor Bay. Once the wind gusts indicated on Windguru reach about 17 knots as on Tuesday 8:00 in Figure 1 below, the South Easter starts catching Three Anchor Bay. Obviously this represents a safety risk since the wind direction is off-shore and already pretty strong. In this particular example the average of 13 knots is quite low, and therefore conditions might be okay. If the average were 16 knots with gusts of 17 knots it would almost certainly be too strong.
Westerly winds are onshore and have a long fetch over the ocean and can make the sea very choppy, but there is less risk of surprises. The 10 knot SW on Wednesday at 14:00 will result in mild whitecaps which are an indication of choppy conditions. Wednesday afternoon is a good example of a worsening trend in the conditions, so if it looks marginal for you at 14:00, don’t go out because it’s going to get worse. Wednesday morning from 5:00 to 11:00 is a good example of improving conditions, so if it looks okay at 5:00 you know it’s only going to get better for at least 6 hours.
Three Anchor Bay also provides some protection from the prevailing South Westerly swell. The swell will break on either side of the bay leaving a calm passage in between. As the swell size increases the passage becomes narrower and when the swell height reaches about 5m (deep sea swell) on Windguru, waves will break right across the bay. The swell period also has a significant effect on the size of the surf. The longer the period, the more water the swell contains and the bigger the surf. As an example a 3 m swell with a 16 second period will break across the bay. A typical swell period is 11 seconds.
Remember when conditions are marginal to watch the swell for some time to ensure you have seen the big sets, there may be as much as 20 minutes between big sets. When the swell is big paddle far from shore, especially rounding the point at Green Point lighthouse! Also be sure to take the right line when returning to the beach. The correct line is shown in figure 2 below. Note that you need to line up the middle of the beach with the left hand carriage way of Helen Suzman boulevard or a prominent, pale gray block of flats in the distance.
There is always a risk of fog with a light onshore wind. Fog combined with big swell presents a significant risk – take a GPS or paddle another day!
Easytide Tidal prediction chart
(External link): EasyTide for Cape Town