ST. PETERSBURG, Fla. (AP) -- As storm forecasters have grown more certain over the years about the potential path a hurricane will take, the popular "cone of uncertainty" used in models has grown smaller.
But widespread misunderstanding of the cone has prompted forecasters to try to improve the tool.
According to the National Hurricane Center, the cone represents the probable track of the center of a tropical cyclone and is formed by a set of imaginary circles placed along the forecast track.
The size of each circle is set so that two-thirds of historical official forecast errors over the past five years fall within the circle, the NHC says.
For the 2017 hurricane season, the error cone for both the Atlantic Basin and eastern Pacific basin will be smaller.
This year the National Hurricane Center will also use a modified tool with a sleeker looking tracking cone.