Had similar problems with a taillight on another car. It would usually work again if you got out and smacked the taillight from outside the car. Basically it was the bulb socket itself not making a full ground/contact with the bulb.
While it's cold again, try fiddling with the bulb and see if it will work. I ran a ground wire from the bulb socket there to a screw inside the trunk and that solved my issue.
While it's cold again, try fiddling with the bulb and see if it will work. I ran a ground wire from the bulb socket there to a screw inside the trunk and that solved my issue.
