I found out about www.windy.com from our friends Shane & Julia at Northland Dive. It has great graphics to illustrate what is happening, much easier to use than Metservice who just give a few words of wisdom on the general area.
Click on the website and either zoom in to the area you want to look at, or enter the area in the search box. You can then click on the area you want to dive and then use the option bar to choose to look at Wind, Rain, Temp, Clouds and Waves.
There are arrows to show directions, a colour graph to indicate speed or sizes and also an actual number is shown on where you have indicated on the map.
What is does lack unless I have missed it is the tides. So back to Metservice for this.