The area of the track forecast cone is drawn so that the actual position of the storm will be within the cone approximately:

Hi

The findings of the National Hurricane Center on the trajectory of a tropical cyclone are subject to a certain margin of error. Such a fluctuation in the prediction of the trajectory of a cyclone is known as a cone, due to the shape of the region where the center of the hurricane could pass has that shape. To form the cone, a series of imaginary circles are placed along the predicted path of the hurricane, in the following time positions: 12, 24, 36, 48, 72, 96 and 120 hours. In this way, the size of each circle contains 67% of the margin of error of the official protocols of the last five years. Therefore, the cone is then formed by the union of the set of circles that represent the predicted trend of the passage of any hurricane.

Explanation:

there are 28 days in feb.