I am no where near a mechanic and by the time I got to the dealership (still
under warranty), it was warm enough that I could not reproduce the sound.

Only on cold days, somewhere around 32F and below, when applying gas
starting from a stand still, I hear some kind of rattling/shuddering coming
from what appears to be behind the center console.  It does not appear to
make a difference whether the engine is warm or not, just seems to be
consistently related to the temperature outside.

I have no idea what is causing this and am looking for any thoughts/advice.

Thanks.