You would have to lose 2lb a week consistently to reach that weight in 16 weeks, and i would have to say that currently at that weight and height i would not consider you to be terribly overweight, although i know of course it depends on build etc, so i don't know how quickly you would lose weight.
All i mean is that WW is about eating healthily and maintaining a lifestyle long term for long term healthy weight loss and maintenance, not crash dieting and losing a lot of weight quickly, which i don't think anyone on here would advocate. Noone can tell you if it would or wouldn't work for you... that's up to you to decide.