I believe it was in Feb '14 or possibly '15 when we had a surprise inch fall at 20 degrees. I saw more wrecks during that event that any other in memory. Granted Knox county didn't bother to put down salt, not that it would have helped a whole lot at those temps, but still. If the Kuchera ratios of 24 to 1 posted earlier are accurate, what little QPF we do get will me maximized and roads will be wild.