It rained without ceasing as Britain's Queen Elizabeth II saw how America's other half lives today when she dropped in for lunch at the desert estate of a man she once knighted.

And since it rains on both halves, even in California, the luncheon party, at the home of publishing magnate and former ambassador to Great Britain Walter Annenberg, got wet.

This was only a problem because Annenberg and his wife, Lee, had planned to take the monarch and Prince Philip on a tour by golf cart of their vast oasis called Sunnylands, a place that made the queen's son Prince Charles once exclaim in astonishment, "You gave this up to go to England?"

But rain, queen and all, six cartloads of guests headed out for their 20-minute tour.

"It poured rain, it didn't stop a minute, but the queen is such a great sport. She brought along her macintosh and they went out anyway. Walter took the queen in his cart and I sent Ambassador John Louis with Prince Philip--I just didn't want to get wet," said Lee Annenberg, a former U.S. chief of protocol.

The British ambassador, Sir Oliver Wright, may have been away from the damp climate of home too long--he forgot his macintosh. But the carts had surrey tops.

Except for that, everything was silver lining.

A presidential jet flew the royal party from San Diego, where they attended church services this morning, to Palm Springs. The queen arrived in a pale-mauve-and-white-checked wool dress and jacket with matching hat of mauve felt--her church clothes.

The only other guests at the lunch, aside from the official British and American parties, were former president Gerald Ford and his wife, Betty, who are neighbors of the Annenbergs. The Fords entertained the queen on her 1976 visit to Washington and the East Coast. (Nancy Reagan was not at the lunch. She was to see the royal couple for the first time tonight at the Hollywood gala she is hosting for them at 20th Century-Fox.)

Just the way the queen does, the Annenbergs flew a personal flag--their yellow and white standard of a Mayan sun god--from a flagpole to indicate they were in residence. Two more flags flanked the entrance to the spectacular main house, designed by the late Los Angeles architect Quincy Jones. These were the American flag and the Union Jack ("I got the last one in California," Walter Annenberg said). The pale pink stucco house stands behind a hedge of oleanders at the corner of Frank Sinatra and Bob Hope drives.

The house itself, filled with memorabilia from Annenberg's five-year stint as President Nixon's ambassador to the Court of St. James's, should have made the queen feel as if she never left home. Among the photographs and memorabilia lining the walls of the Annenbergs' "Room of Memories" is the royal decree designating him an honorary knight of the British Empire. Elizabeth knighted him in 1976 before she set out for her visit to the United States during the bicentennial. "If we were British," Lee Annenberg pointed out during a press tour, "we'd be Sir Walter and Lady Annenberg." An honorary citizenship of sorts is granted in an inscription on a picture of the former ambassador with Lord Mountbatten at the Chelsea Flower Show. Wrote Mountbatten, "Dammit, you look more British than I do."

A picture of Lee Annenberg curtsying to Prince Charles on his 1981 visit to Washington hangs nearby. The curtsy provoked a storm when the picture appeared in newspapers around the country. Though the criticism bothered her, it didn't change her habits. She said she planned to curtsy when she saw the queen today as well.

"I've been doing it since 1969. It's a mark of respect," she said.

The Annenbergs, known for their lavish entertaining, invited no personal friends to the lunch for the queen.

"Suppose we asked four old friends," said Walter Annenberg. "Forty old friends would never talk to us again." So the solution of restricting invitations to just the official party meant limiting the guest list to the queen, Prince Philip and 14 others. In the dining room, the Annenbergs set two tables. At one, the queen sat between her host on her right and former president Ford on her left.

"Normally the queen would sit on Walter's right, but he can't hear in that ear, so she is on his left," said Lee Annenberg.

"Very thoughtful," murmured her husband.

At Lee Annenberg's table, Philip sat between Annenberg and Betty Ford. The dictates of protocol found Michael K. Deaver, deputy chief of staff and, for this visit, the president's personal representative, outranking U.S. Chief of Protocol Selwa Roosevelt and John J. Louis Jr., U.S. ambassador to Great Britain.

The table was set with Royal Copenhagen's Flora Danica china, Georg Jensen's Cactus pattern silver flatware and Baccarat crystal. In the middle were three large porcelain tureens, Flora Danica baskets and pink Boehm roses named for Lee Annenberg. The guests looked out at the snow-flecked San Jacinto mountains in the distance.

After several tastings, the Annenbergs decided on a menu of individual moussellines of salmon with sauce verte, rack of lamb ("pink, very pink," said Walter Annenberg), string beans, glazed carrots, pommes parisiennes and souffle' a l'Erable.

Lee Annenberg, who wore at the lunch a short pale pink silk dress by Andre' Laug, told one recent guest at a trial run of the menu that she had decided not to have a pink dessert because there would be a pink first course. Her husband opted for a Bernkasteler Doctor Riesling 1979 auslese, a 1966 Chateau Lafite Rothschild and a 1970 Dom Perignon magnum. On the dining room walls are Monet's "Stepdaughter" and Vuillard's "The Album," which Walter Annenberg said he had renamed "The Women" because he had seven sisters and the painting has seven women in it.

In his toast to the queen, the former ambassador referred to the " 'great dimension' that the people in Britain have in the royal family--something we don't have in our country . . . It occurred to me it would be appropriate to talk about it--about the dimension I miss here at home," he said.

Asked if he thought this country should have a royal family, he roared, "Good heavens, no--I'm trying to be diplomatic."

After lunch there was coffee in the drawing room, where Walter Annenberg could show Queen Elizabeth his table of what his wife called "his goodies"--a large assortment of crystal figurines representing flowers, clocks, pagodas and other designs, many of them studded with emeralds, rubies and diamonds.

"Eventually I'll probably leave this to the public just as it is," he said last week, touching some of the silver boxes on another table nearby. "It ought to go to the public."

Then, after a few wary glances at the downpour, it was decided to take the golf-cart tour of the estate, which includes a nine-hole golf course famous for its meticulous manicure.

But there was no pausing for a practice shot or two, unlike Prince Charles' 1974 visit to Sunnylands. "He asked if he could have a driver and a golf cart. He doesn't play golf, but polo. He drove around hitting at golf balls with a club," Annenberg recalled. Known to be more than a little protective of his 6,000-yard-long private course, he has refused such pros as Lee Trevino permission to play on it because of the divots they take up. But Annenberg said he had never said a word to Prince Charles about replacing his divots. "I didn't care about that. When it's the prince of Wales . . . he's marvelous company," he said.

According to Annenberg, Charles asked if a "copy" of Sunnylands could be made for Great Windsor Park. "I said that by the time you get through with the zoning commission in your country, I would be long gone."

Among the other treasures in the Annenberg house are paintings by van Gogh, Gauguin, Renoir and Seurat and an original bronze of Eve that Rodin did for his "Gates of Hell"; visitors glimpse the sculpture in the marble-floored atrium as they enter the house. Celadon green walls and the pink marble floors reflect the colors used throughout the drawing and dining rooms.

The queen saw a profusion of cymbidium orchids, potted chrysanthemums and other flowers from the 250-acre estate's two greenhouses. The house's roof soars to 38 feet; all told, there is 32,600 square feet of living space in the house, including a wing with five guest bedrooms and baths. Interior designer Ted Graber, who handled Nancy Reagan's White House refurbishing, decorated the Annenberg residence.

The atrium is where the Annenbergs stage their annual New Year's Eve dinner dance, at which their close friends President and Mrs. Reagan have been regulars through the years. Those occasions may find as many as 90 friends gathering to welcome the new year.

The Annenbergs had two gifts to present to the queen on today's visit: One was a Boehm porcelain California quail, the other a framed letter dated Feb. 14, 1935, apparently to a relative. The queen, then age 9, and her sister Margaret, had signed it with their mother. "We are so sorry to know of your illness and hope that you are feeling better. From the family group," it reads.

As for the queen as a luncheon guest, Lee Annenberg summed it up in three words: "Charming, charming, charming."

At night, it was on to Hollywood, for a dinner on Stage 9 at 20th Century-Fox studios. This happens to be where "M*A*S*H" was shot, and "M*A*S*H" happens to be one of the queen's favorite shows, according to one of her ladies-in-waiting.

But it was no army tents for the queen and her party. Nor were any of the "M*A*S*H" stars on the guest list. Stage 9 had been transformed from the old "M*A*S*H" set into a candlelighted scene of peach-colored tablecloths and salmon and yellow colored poppies and lilies.

The guest list included such names as June Allyson, Fred Astaire, Michael Caine, Richard Chamberlain, Lynn Redgrave, Joan Collins, Marie Osmond, Bette Davis, Buddy Ebsen, Julie Andrews, Samantha Eggar, Greer Garson, Glenn Ford, Irene Dunne, Anthony Hopkins, Elton John, Gene Kelly, Jean Marsh, James Mason, George Murphy, Ginger Rogers, Roy Rogers, Mort Sahl, Robert Stack, Danny Thomas, Robert Wagner, Henry Winkler and Loretta Young--to name but a few.

Frank Sinatra, Perry Como, George Burns, Ed McMahon and Dionne Warwick performed after dinner. That menu included: papaya with bay shrimp, chicken pot pie, and for dessert, toasted coconut snowballs. The wines were Clos Du Bois Gewurztraminer 1981 and Saintsbury Pinot Noir 1981. Chasen's, the favorite Los Angeles restaurant of the Reagans and others in their crowd, catered the dinner. CAPTION: Picture, ROYALTY AND THE MAYORS; Queen Elizabeth II and Prince Philip are greeted by Los Angeles Mayor Tom Bradley in Long Beach, Calif., Sunday, following a lunch at the Rancho Mirage estate of former ambassador to Great Britain Walter Annenberg. Long Beach Mayor Tom Clark is next to Bradley. APPicture 1, the queen leaving church in San Diego yesterday, AP; Picture 2, Lee and Walter Annenberg at their California home, Sunnylands. Copyright (c) 1983 by Alec M Barinholtz/The Desert Aun, all rights reserved