Hot rim, could be sticking brake, or axle bearing.
Chock the wheels, jack up the left rear and turn the wheel, listen for noise such as dragging brake or grinding sound. Chock the front wheels and do this with engine off, parking brake off and transmission in neutral.
If it is something making the wheel hot causing tire melt then it is bearing or brakes.
Also check the tire all the way around, could be something got caught underneath and was rubbing the tire, it may have fallen away but could have damaged the tire and in the heat that can cause the tire to fail as well.
Where are you stranded?
