Noosa has great windsurfing Mr windsurf champ!!
The river mouth is good for flat water and on shore wave slop in a north east wind.
You can sail flat water/bump and jump conditions at Lake Cootharaba in any wind except a westerly.Lake weyba is good for flat water blasting in a westerly.
The open beaches are great down the line wave conditions in a northely and the best thing is you have no crowds to deal with when it does actualy blow.

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There are many more places to sail around the sunshine coast which you will find out about when you get there.
Cheers!