Lake Illawarra launch spots in a SW would include Primbee (need shallow water weed fins), or possibly the Illawarra Yacht club, not so good in from there in SW but a good launch for S/SE with grassy rigging and fresh water tap, and also look at Kanahooka from the Koonawarra bay sailing club, home for the Illawarra windfoilers and wingfoilers. But I can't see any SW in the forecast this weekend, looks all E/ESE?

Gerroa is a short walk in, park south of the crooked river bridge.
Other good windsurf spots in the area are to the north, Sandon Point/Peggies and to the south, Sanctuary Point boat ramp at St Georges basin and Jervis bay. Worth a few drives on windy days to check out the spots and you will find others out there. Also look at a couple of Facebook pages, Illawarra Speedsters and Illawarra Windsurfing for some pics/contacts, there are lots of windsurfers in the area and all in its forms, waves, slalom, foiling, freeride, race boards etc