The Gross National Parade of WMAL-AM (630), now in its fourth year and becoming a zany Washington tradition, kicks off at 2 p.m. Sunday from 18th and M streets NW.

"It grows every year, and one factor is that this is a big parade city. Then, people are antsy for warm weather and here is a chance to let your hair down. We are really an antiparade parade," said Bill Trumbull, who originated the idea with his partner, Chris Core. This year the duo is dressing as the "Chancellors of Trumbull and Core University." They expect 60,000 spectators.

Ernest P. Worrell, the car dealer spokesman who talks to his friend Vern in television ads, will be the celebrity grand marshal. This year 120 units -- which will try to capture capital whimsy in such characterizations as "Ivan the Mole, the CIA Mascot" and "Reagan's Cabinet and Cupboards -- Second Term" -- have signed up. The event had raised $11,000 by Wednesday for the Metropolitan D.C. Police Boys and Girls Clubs.

WRQX-FM (107.3), sister station to WMAL, has organized a unit called "The Great Wedding of 1985, Madonna and Her Wanna-Be's" with Sandy Weaver and Gary Spears. WASH Cancellation

Tom Durney, general manager of WASH-FM (97.1), decided this week to cancel the morning show's scheduled trip to Paris. "We decided it wasn't a good idea. Two airports have already been bombed in Europe and the Qaddafi threat is that he is going to get even. What if it is a disco in Paris next?" said Durney. The "Continental Breakfast" show will continue to travel, said Durney, but "on the homefront." Appointments

John Ogle, a former news anchor and correspondent in New York and London, has joined WCXR-FM (105.9) as morning news anchor. Most recently Ogle has been a consultant to the Virginia News Network . . . Sheree Bernardi is the new afternoon anchor at WASH, joining afternoon deejay John Bodnar. Bernardi previously worked in New Orleans and Norfolk . . . Barbara Thacker is the new promotions director at WDJY-FM (100.3). She moved from another United Broadcasting station, WYST in Baltimore, as did Nic Kuvshinoff, the new chief engineer at WDJY . . . George Barry, a veteran of Canadian broadcasting, is doing the weekend overnights at WGAY-FM (99.5). WETA's 16th

Beginning tomorrow WETA-FM (90.9) will celebrate its "Suite Sixteenth" birthday with an eight-day fund-raising marathon and a schedule of special programs. Tomorrow at 9 a.m. the public station will air a "Best of Desert Island Discs" show and Sunday at 7 p.m. the "10 most beautiful operatic recordings ever made." The list includes Jussi Bjorling singing from "La Belle He'le ne."

This weekend WPFW-FM (89.3) also is kicking off a membership drive, one that will continue until May 4. Today the station features 14 hours of speeches, and tomorrow 16 hours of blues and oldies produced by Jerry (The Bama) Washington. Snyder Series

Jamie McIntyre of WTOP-AM (1500) has prepared a series on Mitch Snyder, the advocate for the homeless. "Mitch Snyder: Martyr or Malcontent?" starts Monday at 6:53 a.m., 11:57 a.m. and 3:55 p.m. and continues through April 27. Public-Commercial Alliance

CBS Radio, along with CBS' news division, and American Public Radio have announced an unusual joint venture to produce a weekday business news package for public radio. The package includes a 30-minute show, "Business Update," anchored by CBS correspondent Frank Settipani, and a 10-minute wrapup. It will debut in afternoon time slots in September.

"That we are 'breaking the mold' is a certainty," Richard Brescia, senior vice president, CBS Radio Networks, said of the agreement between a commercial and public network. The announcement came at the annual American Public Radio conclave this week in San Diego. Awards

Ron Nessen, vice president of news for Mutual Radio, is scheduled to receive the Alumni Recognition Award from American University tomorrow . . . The Academy of Professional Broadcasters is honoring the "All the Way" team of Pyramid Communications tomorrow in Atlanta. The show, hosted by Mandonna Sahahvari and Chris Powell, is heard on WKYS-FM (93.9) Sundays at 11:30 p.m. Talent Search

Only seven days remain to get your home tape into WWDC-FM (101.1) for its annual rock and pop contest. The top winners receive recording time at the Unique Recording Studio in New York. Artists and bands should have their cassettes at the station, delivered either by mail or in person, by 5 p.m. Thursday. Charity Calendar

WTKS-FM (102.3) is sponsoring the annual "Bike-for-Sight" ride tomorrow around Washington's famous monuments. Participants will be raising funds for the Prevention of Blindness Society of Metropolitan Washington. Bikers are to gather on the west side of the Tidal Basin at 8:30 a.m. for the five-mile ride.