Which Tide?
A good start to your questions would be to check this link out.
http://magicseaweed.com/content/surf-forecasting.php
Tony Butt is a regular contributor to The Surfers Path and some of his articles are summarised here but bear in mind he is based in the northern hemisphere.
His book would perhaps be worth buying for a more in depth read.
It's a complex topic with many related factors. There are a few things to note...
The greatest factor is the place you intend to surf. Most reefs and points (rock bottom) have a preferred tide they break on and experience will teach you what that is.
Beaches (sand bottoms) are always in flux so the banks are forever changing and it takes up-to-the-moment local knowledge to know what tide is best for the bank in question. Deeper banks generally prefer low tide and vice versa, but there can be a wide array of preferable tides even on the one beach. Also, as a general rule, shorebreaks are better at high tide, as at low tide size is shaved off the swell and the quality deteriorates as the swell crosses the outer bank.
As you can see there isn't any universal rule, it all depends on where you plan to surf.
Not to be discounted is the carpark bluff, often espoused as rock-solid science and intended to make the protagonist sound awfully intelligent while offering an excuse not to go out. "Yeah mate, it's eight foot and offshore but I'm gonna wait till the tide starts to drop and it gets good."
There's also the pseudo-science: "Yeah mate, the lull was caused by the change in the tide." This one can be repeated at any time of the tide cycle without being questioned.
So true Stu, thats hilarious :)
Theres another that remains a mystery in some ways to me, tide draining out, often brings in the swell to protected corners or sheltered point breaks on groundswells.
You would think, well i used to think tide rising would bring in swell, but at some spots especially indo and island coral passes, the swell seems to get greatly bigger on tide going out.
Even if the swell is dropping.
I guess the outer currents have something to do with it with the water so deep offshore..Id like to hear more on that.
We all know tides affect wave shape and that different banks work on differnt tides. And different wave periods will respond to tides and banks differently too.
But how do you pick the tide to go out on? I often hear someone say they are waiting for the tide to come in/go out to improve the surf - is there some general rules that work for a given tide/swell combination or is it just down to experience&intuition? Is every place different or are there some rules of thumb?