Starting Monday, May 9th, McDonald's will nationally launch their latest addition to the McCafé beverage line - Frozen Strawberry Lemonade. The drink, initially spotted in testing at a Jacksonville, FL location is a 270-calorie frozen slush that boasts a sweet, tangy hybrid of strawberry flavored syrup into a lemonade base. Just in time for the summer season? Yes, just in time for the summer season.