The legend of Phoebe Snow was entirely fabricated for the sake of advertising, and so much misinformation seems to be perpetuated about her. Lackawanna's pre-Phoebe ads were as boring as those from every other railroad. Phoebe was invented in 1903 by adman Calkins and the campaign was a rapid success. Legend has it that the name came from the heavy, black cleaning lady in Calkins' New York City office building who was named Phoebe.
Snow is an obvious last name.
The jazz-singer Phoebe Snow freely admits that she took her name from the train, though she is not at all a railroad buff. There were many models representing the fair maiden. Comtemporary writings at one point called Phoebe the most popular lady in America, about on the scale of a Cher or Madonna today. There were numerous articles written, and Milton Bradley even offered a board game in the 1910s. Every once in a while one pops up on eBay.