Can one lose 33 pounds safetly in 3 months?

35 lbs in 3 months is about 3 lbs /week. That's doable, but will require serious dedication. You need to figure out your calorie needs, how many calories you are eating, and then adjust your diet to a suitable number. Probably in the 1200 -1500 cal range. Weightwatchers would be an Excellent way to achieve this, although you can create your own diet if you read up a bit first.

Start by scrapping everything obviously fatty and sugary from your diet. No sodas, Nothing deep fried, no alcohol. For a cooked meal, 1/2 your plate should be vegetables, 1/4 protein(meat), 1/4 carbohydrates(rice, pasta, potatoes etc).

Try to be physically active for one hour daily. Walking is fine, jogging is better. you should get a bit sweaty and winded.