i left the nt in 1995 but i used to windsurf at casuarina beach . this is the time of the year when the wind is at its best the dry season is also known as the windy season and you don't have to worry about stingers . as far as crocs go i never saw one i think the tiger sharks ate them

you could also try nightcliffe beach depending on wind direction although i think rigging and launching could be a problem there