If the temperature dips to 18 degrees Fahrenheit (without the wind chill), the company will give New Yorkers two free toppings on their frozen yogurts.
The "Let It Swirl" campaign kicks off on
the first day of winter, Sunday, and ends on Jan. 10, the company's fourth anniversary. The 18 in 18 degrees signifies the 18 toppings available at Pinkberry.--Nina Lentini