LONDON (AP) _ Sir Noel Coward, the late playwright and songwriter, was also a talented amateur painter, as a show of his paintings revealed Thursday.

The 30 pictures, mostly colorful landscapes, marine views such as ''The White Cliffs of Dover'' and beach scenes in England and Jamaica where he had a vacation home, will be sold in London Feb. 18 to benefit theatrical charities.

Auctioneers Christie's said they expect nearly $500,000.

Coward, a sophisticated and witty entertainer not given to false modesty, made a typical comment when a London gallery showed some of his pictures in 1955.

He wrote in his diary that although he was ''not really good enough yet for an exhibition ... compared to some of the pretentious muck that is shown month after month in the London galleries, my amateur efforts appear brilliant. They have a sense of color and design.''

Graham Payn, Coward's friend and executor, said the playwright had advice from several artist friends and he always painted indoors, from memory.

''Noel tried painting outdoors once, at St. Margaret's Bay in Kent, but he couldn't stand the wind and the flies,'' Payn said.

''He was obsessive about his painting. He wouldn't stop for lunch, tea or a drink when at his easel.''

Coward was 73 when he died in Jamaica in 1973. He wrote 50 plays, 25 films, hundreds of songs, a ballet, poems and stories. He didn't sell his paintings, but gave some away as gifts.

His biographer, Sheridan Morley, said Coward painted a picture of Nell Gwyn, King Charles II's mistress, when he was only 10 but he didn't start serious painting until his early 30s.

Coward was advised by another famous amateur artist, Prime Minister Sir Winston Churchill, to change from watercolor to oils because it was easier to cover up mistakes.

Later, because of an allergy to the turpentine in oil paint, Coward changed to gouache.

''It was in Jamaica that he achieved his best results,'' said Morley. ''He somehow caught the essential spirit and the many moods of that lovely island.''

Payn said that after the February sale he will distribute the Coward works he has retained among theatrical museums in Britain and the United States.