Frosty the Snowman (1969)

A discarded magic top hat brings to life the snowman that a group of children made, until a magician, professor Hinkle, wants it back, and the temperature starts to rise. Frosty will melt or no longer be a jolly soul, if the kids cannot get him away from Hinkle and warm weather, so he hops a train to the North Pole with young Karen.