Can I lose 20lbs in two months?

I want to lose 20lbs by August (if possible). I'm not going to be shy I'm a female, 19years old, 5'3" and I weigh 170lbs. I know the weight for my height isn't healthy and that's one of the main reasons I wanna lose the weight. I am a vegetarian so I do not eat meat or fish and please don't tell me I need to be because I've been a vegetarian for 3.5 years and I'm not going back. If I could get some advice on how to lose 20lbs by August it'd be great thanks!