Your eyes are not deceiving you. That is ice on the ground this morning around my tree here in Texas. Last night we had an ice/sleet thunderstorm and this is what I saw this morning when Maya went to her bus stop. Luckily, I didn't get around to planting flowers this past summer or they would no longer be.
So there you have it. It can get cold enough long enough for ice to build up on the ground here in San Antonio (where yesterday it was close to 80 degrees!).