Up until this season Mid May is the windless part of year in Melbourne. The winter northerlies kick in after that and Greens Point in Brigthon is the spot for the area you are tlaking about.

BUT due to the in different winds we could get any thing or nothing. Keep an eye on Seabreeze Victoria forum as we do a where are you sailing for every weekend post. Plus check out the Windsurfing Victoria website for site and other details.
www.wv.org.au

As Windrider says, winter we get pretty consistent northerlies, a good place to check out is Rye, the wind always seems to be fairly consistent down there from about June through to August. Its probably about an hour drive south east from St.Kilda. Do a search for Rye Victoria in google earth, you will see where I am talking about. Only downside is its usually pretty on-shore there, great for speed inside the sand banks and is quite shallow a fair way out, but not great for jumping.