
The groove where the wear indicator is located is 1/16 inch (1.6 mm) shallower than elsewhere on the tire. If the tread has worn so that the indicator is exposed, replace the tire.
Worn out tires have poor traction on wet roads.
Temperature
Tire Service LifeHonda Civic Owners Manual. Traction
The traction grades, from highest to lowest, are AA, A, B, and C.
Those grades represent the tire's ability to stop on wet pavement
as measured under controlled conditions on specified
government test surfaces of asphalt and concrete. A tire marked
C may have poor traction performance.
...