When forecasting the surf condtions there are many things you need to look at when making the prediction, not only the wave height, you need to look at a combination of:
-Wave Height
-Wave Direction
-Wave Period
-Wind Speed/Strength
-Wind Direction
If you look at all of these you can find out roughly what the surf will be like at any break anywhere.
How to Forecast Wave Height and Direction.
I put these things together becasue on most charts they can both be done together on the same exact chart. The best thing I have found to forecast wave height and direction are the Scripps WAM (Wave Amplitude Models). These are VERY accurate and VERY east to use. They are animated and forecast to 120hrs ahead and work like this, you look at the amount of hours ahead you want to forecast at the top then look down at the chart for the arrows firstly, if they are pointing and heading towards the coast your forecasting for...Your in look! That means the waves are heading towards the coas. The next thing to do is look at the colour then compare it on the scale at the top and see what number it is near, the number it is on or nearest to equals the height of the wave in foot (this is not swell height but is wave height).
The next most accurate charts I have found are the Athens Uni Charts work in exactly the same way with a few minor differnces; They firstly are not animated which can make comparing the colours on the charts to the scale at the bottom easier, they only forecast 3 days ahead but are very accurate for hese 3 days and the other differnce is the height is given in meters, they are simple to use (even easier than the Scripps WAM charts). The next method is the MUMM animated chart these are a little differnt to the other 2 in that they don't give a swell direction only a height, the height is given using the same sclaes method. The final method but hardest is by using basic Pressure or Synoptic charts (there are 3 types of these on the magicseaweed.com forecast page. To use these you first need to know that the wind/pressure goes anti-clockwise in a low pressure system and clockwise in a high pressure system. You can tell the systems a part becasue on the black an white charts on the forecasts page have a 'H' for High and a 'L' on Low pressures in the center of them. If they do not have the letters on you can tell them apart by the shapes, these are hard to describe in words so the best way I would say are by looking at the charts with letters and then then look at the shapes, they are quite differnt which is east to notice after a while of using them. The tighter the lines a together the stronger the winds/pressures so the bigger the waves.
How to Forecast Wave Period.
Wave Period is the average distance between each wave and is very simlar to forecast as wave height and direction but yo need to sue differnt charts. The Best one I have found for this is the Scripps WAM. The arrows on the chart mean the same as on the WAM's (wave direction). But the colours this time are not height but wave period measured in seconds, you compare it to the scale just like on the Wave height charts. The other chart is the [urlhttp://magicseaweed.com/index.php?option=content&task=view&id=18]NOAA Charts[/url], these work in exactly the same way as stated above so I wn't explain that again.
How to Forecast Wind Speed, Strength and Direction.
Thw wind is easy to forecst but again use differnt charts and a couple of differnt methods. My personal favourite charts is the BBC wind model it is the most accurate chart (in my opinion) and is simple to use. The arrows indicate direction (pretty obvious) and the thicker and bigger the arrow the stronger it is. There are down sides to this model though:
a)It only forecasts 3 days
b)It doesn't give the speed in knots or mph
Despite these I still like them becasue of the accuracy and ease of use.
The other chart which is just as good is the NOAA wind chart this gives a 180hr forecast and works like a WAM chart the arrow shows direction (did I really need to say that
), and the colours give a strength. The other main way is Pressure Charts, they work just as I said above in the 'How to Forecast Wave Height an Direction' so if it's still unclear read back throught that a few times and I hope it makes some sense, if not feel free to ask!
It is important in my opinion to use MANY chjarts when forecasting then you can find an average height, if one chart says 2ft and another 6ft it is unpreditable where as if you only use one chart saying 6ft it could be 3 a lot smaller than you expected so use many charts to help you!
That is the how to over. I hope it sheds some light on to the subject, I mainly made it for compelte begginers because recently a couple of people have been curious "How do you forecast surf for yourself?" So I thought this maye come in hady for a couple of people at least....Hope it did. I know It's not the best and if anyone else has anymore info I didn't include (or maybe that I got wrong) please feel free to add more in this topic.
Here are some other sources on Surf Forecasting.
Info on wave bouys by Ben from Magicsaweed.com
Swell Generation by Ben from Magicseaweed.com
How to read Pressure Charts by Ben from Magicseaweed.com
