GREEN BAY, Wis. -

Green Bay police are investigating whether the extreme cold may have been a factor in the death of a 38-year-old man.

Police found the man's body on the driveway outside his home Monday morning.

The man lived alone. Police said there were no obvious signs of physical harm to the man.

WLUK-TV reported temperatures in the neighborhood Monday morning struggled to get above zero.

Police are withholding the man's name until relatives are notified.