Long story short… freezing rain occurs when the atmosphere is warmer higher up than at ground level. It’s called an inversion. Usually it’s a shallow layer of warm air fairly close to the ground (below about 5000 ft) that precipitation falls through and melts. There is insufficient time for it to reform into snow before hitting the ground. Since the ground is frozen and the temperature is below 32 degrees, it will freeze.
We expect the lower atmosphere to continue cooling this afternoon so if any additional precip develops, it should fall as sleet or snow. Knock on wood.