If Wayne Newton can quadruple his annual humidity intake by spending the Fourth of July in the Nation's Capital instead of Las Vegas, surely the rest of us can sweat it out with him.

Actually, spending this Independence Day weekend close to home and out of doors is a no-sweat proposition, considering how much there is to do. The tough part is deciding exactly how and where to do it.

Glad you brought that up.

Nightfall's arrival will be announced by fireworks, as opposed to mosquitos, starting as early as Saturday, and continuing through Monday all over the place. The displays range from the official, Zambelli-produced version above the Mall on July 4 -- one of the largest displays on the East Coast this year -- to the more modestly spectacular version on the the lake in dontown Washington, Virginia, 70 miles west.

Through Monday, a short walk or drive will run you smack into someone's Fourth of July parade, picnic, carnival, concert, sack race or pie-eating competition -- mostly for free. And it doesn't much matter whether you live in Washington, D.C.; Washington, Va.; or in Bowie, Md., either; the Fourth of July is everywhere.

So is this roundup -- which begins downtown, and, in the spirit of the holiday, explodes colorfully outward. DOWNTOWN WASHINGTON is home to the most extensive Fourth celebration on Monday, so things start early with a 7 a.m. flag-raising ceremony at the Capitol reflecting pool that includes an "America's Youth in Concert" performance, featuring top musical students from every state, and a reading of the Declaration of Independence by Efrem Zimbalist Jr. Starting at 10 a.m. and heading up Constitution from Seventh to 17th NW: the National Independence Day Parade, whose 140-plus groups include Washington's own H.D. Woodson Senior High School marching band and the Brentwood Eagle-ettes drum and color guard from Mt. Ranier. Early arrivals will be entertained by strolling choirs, square dancers, jugglers, clowns and magicians. Besides goings on at the American Folklife and Indian Heritage festivals on the Mall, afternoon concerts will take place at the Sylvan Theater south of the Washington Monument by Fast Rodney (rockabilly) and the U.S. Air Force Airmen of Note, among others; and by others at the Constitution Gardens stage, on the Ellipse behind the White House. At 6, the U.S. Army Blues Band performs on the main stage, just west of the Washington Monument; at 7:15, it's time for Wayne Newton and his orchestra. The National Symphony Orchestra performs with soprano Leontyne Price at 8 on the west lawn of the Capitol building. The fireworks on the Washington Monument grounds start at 9:15 -- produced by Zambelli Internationale and choreographed by Bruce Bassman to music you'll find on Monument grounds loudspeakers and on WMAL (630 AM). Bassman, who designed the fireworks for Washington's "Belgium Today" and "Scandinavia Today" programs and for Macy's Fourth of July celebration in New York, says the show's "final thunderation" is made possibly by the detonation of 1,600 shells in the last five minutes -- all in red, white and blue, naturally. All day Monday, Metrobus and Metrorail will cost 50 cents (coins, no farecards) and will operate on modified Saturday schedules -- except after 6 p.m., when trains will approach rush-hour frequency and Metro will add 180 buses downtown and at rail stations. Details at 637-2437. SATURDAY

LAUREL celebrates early with sky-diving at noon at McCullough Field (Montgomery Street between 8th and 9th), food and games, live bands, a car bash (three of them, painted to look like police), a parade at 2 and fireworks at about 9. 490-8384 or 725-5300. FORT BELVOIR parties with activities starting at 10 on Pullen Field and including carnival rides, game booths, food, sky- diving demonstrations, clowns and military displays. Music and magic shows through 9, when the fireworks start. Fort Belvoir also plans a 50-gun salute Monday at noon, at the Long Parade Field. FAIRFAX CITY'S parade starts at 11 at the Massey Building on Route 123, with the Redskins' Hogs as grand marshalls, balloon rides at 10 at the Massey Building, then at 6 at Fairfax High School, where there's food and drink, concerts by the Fairfax City Band and a 150-member drum and bugle corps, and fireworks at 9:15. SUNDAY

The festivities start at 1 in MORNINGSIDE, Maryland, with country and western music and dancing, games, pony rides, food and fireworks at about 9, at Douglas Patterson Park, off Suitland Road near Allentown Road. 248-1260. COLUMBIA'S typically impressive Fourth is also on July 3 this year and starts at 3:30 in the afternoon with a parade at Columbia Mall. At lakeside there'll be everything from lemon sticks to beef barbeque, plus music at 6 (Overland Express bluegrass), paratroopers aiming for the lake at 8:15 and fireworks by Zambelli (including one "Italian Bomb" reportedly never before seen in Maryland) at 9. Parking's $1 per car. 301/992-6060. In POOLESVILLE at the Polo Grounds (Hughes Road, north of River Road), there's a 4 p.m. polo game -- what else? Good question. How about food and drink, and fireworks at dusk? 428-8927. ARLINGTON COUNTY plans an hour of fireworks over Barcroft Park, 4100 South Four Mile Run Drive starting at about 9. MONDAY MARYLAND

ROCKVILLE offers a free program at Richard Montgomery High School stadium, 250 Richard Montgomery Drive (off Rockville Pike), featuring music at 6:30 by the Free Spirit Band, skydivers and a hot-air balloon launch at about 8, and music by the Rockville Concert Band and Rockville Community Chorus up to fireworks time at 9:35. The Fourth of July parade in TAKOMA PARK starts at 10 at Carroll and Ethan Allen avenues and heads toward the municipal-building reviewing stand on Maple Avenue. Races and games start at 5 at Takoma Park Junior High, followed by a U.S. Navy Country Currents concert at 7:30, and fireworks at 9:15. CLINTON'S 15th annual Independence Day parade gets started at 10 a.m. at Surrattsville Senior High, 6101 Garden Drive, and the roughly 70 floats, bands, fire companies and youth groups wind up at Clinton Plaza Shopping Center about 1. Wild World in LARGO has waterworks -- and an $11.50- per-person gate -- but also fireworks, with a $6.50-per-person charge after 5 p.m. The fireworks are Zambelli, the music is country, and the phone number is 249-1500. GAITHERSBURG calls its celebration an "Old Fashioned Fourth" at Summit Hall Park, West Deerpark Road, 10 to 5: carnival games and rides, races, egg tosses, hog-calling, bingo, watermelon-eating contests, country and bluegrass music and a vaudeville-style circus show at noon. Admission's free, as it is at the fireworks display at dusk in the Montgomery County Fairgrounds off Chestnut Avenue. In BOWIE, Allen's Pond Park, off Route 197, is the site of a concert by the Country Grass Band and other entertainment starting at 6, for a $1-per-car admission. Fireworks at about 9 above the amphitheater. Fireworks at 9:15 follow a 7 p.m. concert at Buddy Attick Lake Park, Crescent Road off Kenilworth Avenue in GREENBELT, by the Greenbelt Concert Band, free. The U.S. Marine Band performs free at 7:30 in COLLEGE PARK'S annual Independence Day celebration at the University of Maryland's Byrd Stadium, followed at 9:15 by fireworks. 445-4500. Fireworks also end the day in NEW CARROLTON, which hosts its annual "Knockout" at Turner Field (at Robert Frost Elementary) and Beckett Field (off 85th Avenue), wherein families compete in balloon tosses, tug-of-war, log Park for a picnic supper and fireworks at dusk. 301/663-8703. VIRGINIA

FALLS CHURCH will send its fireworks up at 9 over George Mason High School, Haycock Road at Leesburg Pike, accompanied by patriotic music, ice cream, hotdogs and drinks. 241-5077. Fairfax County'sMOUNT VERNON DISTRICT celebrates at Mt. Vernon High School with baseball and softball games at 1, plus pie-eating, sack races, dunk-a-coach water games and music by the Mount Vernon Community Band, the Jim West Band and the Minotaur rock band. Fireworks at 9:15. No fireworks planned at the McLEAN COMMUNITY CENTER, 1236 Ingleside Avenue, but from noon to 6 there's music, storytelling, pie-eating contests, carnival games, a Moon Bounce, barbequed lunches, craft exhibits and a nine-foot Uncle Sam. 790-9248. At LAKE FAIRFAX PARK, just off Leesburg Pike on Route 606, fireworks start at dusk. Swimming, picnicking, boating, miniature train rides and hiking are free to Fairfax County residents, $3.50 per out-of-county carload. 471- 5415. LEE DISTRICT PARK'S fourth annual Fourth starts at 9 at the park, 6601 Telegraph Road in Rose Hill (two miles below Beltway Exit 2-S), with baseball and softball games, the Blue Sky Puppet Theater at noon, bluegrass and gospel music at 1 and a one-man banjo show at 3. Also pony rides, clowns, barbeque, a snake and crocodile show at 2, country music at 4 and rock at 6. Fireworks at 9, followed by the Nigel Hill rock band until 11. 922-9840. In VIENNA, the party starts at noon on the grounds of the Vienna Community Center, 120 Cherry Street SE with children's, country and rock music, magic shows, arts and crafts exhibits, a flea market, games and races. Also a greased-pole climb at 4, a Vienna Community Band concert at 8, and fireworks at 9:15. 938-8000. The town of WASHINGTON, VIRGINIA, 20 miles west of Warrenton on Route 211, celebrates both the Fourth of July and Rappahannock County's 150th anniversary with a day-long fair on otherwise sleepy streets: craftspeople, white elephant and book sales and an afternoon parade of fire and rescue equipment, costumed dancers, horse-drawn buggies and pet goats, led by the Pawtomack Ancients Fyfe and Drum Corps. There's also a reenactment of the first meeting 150 years ago of Rappahannock's gentlemen justices; and columnist James J. Kilpatrick, as before, scoops out homemade ice cream at the Trinity Church's concession. Foot races and hot-air balloon rides in the afternoon take place on the 12-acre estate of Mr. and Mrs. William M. Carrigan, who, as they have for the last 22 years, also put on a professional fireworks show over the small lake on the property. "I came from the Middle West," says Carrigan, "where the Fourth of July was celebrated as a great day by the whole town, and celebrated homestyle. When we got that place in 1960 right next to the courthouse, it was so public that we couldn't have a private celebration, so we opened it up. Been doing it ever since." On the off chance that you've got to drive to Albany or somewhere this weekend, you haven't missed all the fireworks. ALEXANDRIA waits its usual week to celebrate both Independence Day and its own birthday -- next Saturday, July 9. There's a day-long festival on Market Square in Old Town, with more than 30 arts and crafts exhibits, bluegrass music, clog dancing, food and drink. At 7 in Chinquapin Park, off King Street next to T.C. Williams High, the Milpercen Chorale performs patriotic music, the Bob Lewis Orchestra does its big-band act, and the fireworks do their big-bang act.