The wind speed indicator is at the Spit on the mast at the VMR so I always take off 5 knots to allow for the protection from land .

However on a fast out going tide using a SE wind as an example what do you allow for the increase in apparent wind.

In other words 20 knots on the chart ,take 5 knots off , then add say 3 for apparent wind due to tide, giving 18 knots .

How much does tide effect the wind over the bow ( apparent ) on the BW .