You lose weight when you create a deficit between the calories you eat and those you burn. A pound of fat equals 3,500 calories, so to lose 30 pounds, you'll need to create a deficit of 105,000 calories. To achieve your goal in the two months, you would need to create a deficit of about 1,750 calories per day -- an unrealistic target.
Most major health organizations, including the Centers for Disease Control and Prevention, recommend a more moderate deficit of 500 to 1,000 calories per day to yield 1 to 2 pounds per week lost. This rate is recommended because you can tackle it pretty readily -- it requires you to reduce food intake and move more without starving yourself or extreme exercising. You also avoid nutritional deficiencies, exercise burnout, a stalled metabolism and muscle loss.
Even if you could somehow create such a large daily deficit, it would result in a loss of almost 4 pounds per week for the eight weeks. Losing faster than 3 pounds per week for more than the first week or two of a diet plan can lead to health complications, including gallstones.