It doesn't happen as often as it used to, but it will happen tonight when the Washington Opera opens its season: an American singer at the height of her career will sing professionally in her own country for the first time.

Janet Perry, born in Minneapolis, has been heard in the U.S. only on records. Unable to make a steady living here as an opera singer, she went to Austria when she was 21 and got a steady job in the tiny Linz opera house, and in the last 13 years has become one of the leading singers in Europe. "Janet Perry is American?" a European opera impresario asked in surprise when her name came up in conversation a few days ago. "I always thought she was English."

When you talk to Janet Perry, she doesn't sound English, but she doesn't sound quite American either--she has a sort of generalized European accent--not exactly German, French or Italian, although she is fluent in those languages. It is the accent of an American who has not been speaking English much since around 1970.

"My friends and family tease me about the accent all the time," she says--with an accent--"but it's just what happens when you use other languages and don't use English day after day, year after year. I don't really mind losing my American twang; that's good for a singer. You know, the language you speak affects your singing voice--whether the throat is open or closed, whether you produce sounds from the front or the back, whether the sound is nasal or not, easy or tight."

Perry is the latest American soprano in a long tradition--one that dates back at least to 1879 when Lillian Norton of Farmington, Maine, made her operatic debut in Milan under the name of Nordica. After triumphs in Italy, Germany, France and even Russia, she finally got around to her American opera debut in 1883. The 100th anniversary of that debut will be Nov. 23, and somebody should organize a concert by American singers--perhaps at La Scala--to mark the event. Since Nordica, it has become easier for American opera singers to make a decent living in their own country; Rosa Ponselle did it beginning in 1918, and Beverly Sills did it in the 1950s; Maria Callas, born in New York, was actually offered a contract by the Metropolitan Opera in 1945 (when European singers were hard to import because of World War II), but decided to build her career in Italy before conquering America.

Incidentally, the tradition of American opera singers' changing their names seems to be even stronger than the tradition of building a career overseas. Ponselle began as Ponzillo, Sills as Silverman and Callas as Kalogeropoulos. Janet Perry's family name used to be Pariseau, but an ancestor changed it when the family moved south from Canada. "Pariseau" might be a more useful name for her than Perry; she is coming to town in an opera production that originated in Paris, where the critics found her voice "ravissante . . . e'tonnante."

Would she like to do more singing in America? She certainly would. Between two performances as Despina in "Cosi fan tutte," she is going to Minneapolis to give her first professional recital in the town where she was born. The program will include Brahms, Schubert, Debussy and one American song. If that sounds like a foreign prima donna going into a new country and working some native material into her program, that may be because that's what Janet Perry is.