An apparatus and method for modifying the temperature of a bed environment. In preferred embodiments, the invention is a self-contained, forced air bed warmer which pre-heats the interior sheets and covers of a bed to provide a controlled micro-environment that facilitates relaxation into restful sleep on cold nights. Preferred embodiments include an air conditioning section comprising a body portion and a handle portion, said air conditioning section having an exterior surface that is adapted to receive an edge of a bed cover between said body portion and said handle portion; a fan; a heat transfer element; a temperature sensor; a control circuit connected to said temperature sensor; a timer mounted within said air conditioning section; and an elongated air delivery section having two ends with an air entrance at one end and a primary air exit at the other end.