The invention provides a portable hand-warming apparatus for athletes that is easily attached and detached from the athlete\'s clothing but remains safely unobtrusive with the movement of the player during an athletic event. The apparatus is made of multiple layers of materials to reduce moisture, insulate, and resist wind and water. In one specific embodiment, the apparatus may be used to warm the throwing hand of a baseball or softball player while inactive during play, such as between pitches or while playing in the field.