Free outdoor entertainment is plentifully available this summer for Northern Virginians who like communing with nature and the arts.

If you're lucky enough to live in or near Arlington, you can even pick up the phone and let your fingers do the finding of free festivities.

The performance and visual arts section of the Arlington recreation division has an arts events hot line, 5582165, which is updated every 24 hours. The hot line provides recorded, round-the-clock details of ongoing, free events scheduled through August.

Arlington's full summer season of performances takes place in the spacious and svlvan Lubber Run Park Amphitheater.

A fully staged play for young people and a musical comedy production highlight the season. There also is a series of film classics and a variety of music and dance concerts.

After the Fourth of July fireworks, the next big event is "Tarradiddle Tales," sponsored by the Children's Theatre of Arlington beginning at 8 p. m. July 7, 8, 9 and 14, 15, 16.

Arlington Theatre Associates' production of "Kismet" debuts on the large amphitheatre stage Aug. 11 and continues two weekends, at 8.30 p. m. Aug. 12, 13 and 18, 19, 20.

Three vintage Hollywood movies, part of the Arlington Film Workshop series, will be shown at 9 p. m. on three dates. The original version of "A Star is Born," with Janet Gaynor and Frederic March (1937) on July 11; "Farewell To Arms," with Gary Cooper and Helen Hayes (1932) on July 20, and "Scarlet Pimpernel," with Leslie Howard and Merle Oberon (1935) on July 27. All showings are outdoors.

Concerts scheduled at 8 p. m. include the U. S. Army Blues on July 10; Arlington Dance Theatre on July 22; Arlington Recorder Society on July 23; the Commodores, a U. S. Navy Stage Band, on Aug, 3, Jazz Masters on Aug. 14; the Arlingtones on Aug. 15 and Sweet Adelines, Potomac Harmony chapter, on Aug 16.

Other counties and cities in nearby Virginia suburbs which will offer smaller-scale free events for the public include Alexandria, Fairfax County, Fairfax City and Falls Church.

An annual "Summerscene" series of outdoor concerts and shows is sponsored by Fairfax City on Thursday at 8 p. m. on the west lawn of City Hall. In case of rain, all events will be held in the Fairfax High School auditorium, 3500 Old Lee Highway.

The Band from Tin Pan Alley, a five-man jazz and Dixieland group, will perform tonight. On July 13, the 65-member City Band will give a one-hour concert of show tunes and marches, including special pieces for children.

Two other concerts by the City Band are scheduled for July 20 and Aug 3.

A bluegrass program by the Hobb Sisters and Bob Goff Jr., a new Fairfax City group, is scheduled for July 27. The concert on Aug 10 will feature country rock musicians, the Virginia Renegades.

Two special children's programs are Fairfax City's final events this summer. The Bob Brown Marionettes will present "Wonderful, Wacky World of Puppets" on Aug. 17 and the husband-and-wife team Denny and Lee will bring the season to a close with the annual children's magic show Aug. 24.

Call the Fairfax City news hotline at 273-1776 for information on any last minute schedule changes.

Fairfax County will hold a free summer concert series at various indoor and outdoor locations in july and August. Up-to-date information can be obtained by calling 691-2671, Monday to Friday, 8 p. m. to 4.30p. m.

A program July 7 by the U. S. Navy Port Authority band will begin at 7.45 p. m. in Bailey's Community Center, 5920 Summers Lane, Bailey's Crossroads.

The Fairfax Symphony will give three evening concerts, tentatively set for July 20, 25 and 27 at 7.45 p. m. in different parts of the county. Locations will be announced at a later date (call 691-2671).

A band concert by the U. S. Navy County Current will begin at 7.45 p . m. on July 31 at Lake Accotink, 4651 Heming Ave., Springfield. The U. S. Air Force group, Mach One, will play at 7.45 p. m. on Aug. 11 in James Lee Community Center, 2855-A Annandale Rd., Falls Church. A U. S. Navy jazz concert by the Commodores is scheduled Aug. 22 at 7.30 p. m. in the Mclean Community Center, 1236 Ingleside Ave.

Fairfax also has two puppet productions now touring county playgrounds through Aug. 4. "MAd Isn't Bad" and "Being Green" will be performed three times daily. For times and locations, call 691-2671, the county performing and fine arts division.

Alexandria has many arts events scheduled, including a free series of children's performances, poolside concerts and several ethnic festivals in Market Square. Two community theater groups have summer productions with reasonable admission charges.

The Tuesday afternoon "Children's Charmers" in July include the Palisades Theatre Company on July 11. Cowboy Wimpie on July 18 and Kalunka's Cirkus Puppets on July 25. This free series begins at 1 p.m. in Fort Ward Park, 4301 W. Braddock Rd.

The 1 p. m. children's program continue at Chinquapin Center in August with a variety of dance, music and crafts events for the kids on Aug. 1, 8, 15, 22, 29; admittance is $1. Registration is required, call 750-6325.

Free poolside concerts at 7.30 p. m. begin on July 11, when Kingsmen, the Kings Park Civic Band, plays at Southern Towers, Seminary Road and Shirley Highway. Bobbe's School of Dance will perform at the same location on July 25, followed by the Jazz Masters on Aug. 1, the Riverside Ramblers Dixieland band on Aug. 15 and the Alexandria Sweet Adelines on Aug. 29.

Summer ethnic festivals include a Celtic program on July 15 (rain date. July 16) and a Far Eastern Nations one on Aug. 12 (no raid date announced). Activities from 10 a. m. to 5 p. m. in Market Square feature music, food, arts and crafts. No admission is charged.

A special international concert by the Swiss Folklore Group will be sponsored Aug. 1 in Fort Ward Park Amphitheatre, 4301 W. Braddock Rd., 7:45 p. m. Admission is free.

For more information on any of Alexandria's events, call the Alexandria Department of Recreation and Cultural Activities, 750-6325, during regular weekday business hours.

The Little Theatre of Alexandria will open its summer production of "The Quibbletown Recruits" July 28 on its professional stage at 600 Wolfe St. Performances continue July 29, 30 and Aug. 3, 4, 5, 6 and 17, 18, 19. All evening curtains are at 8:30 p. m: Sunday matinees are at 3 p. m. Admission is charged. Call 683-0496 for more information.

Port City Playhouse will perform "The Fantastiks" at the National Puppet Theatre, 815 1/2 King St, July 27-29. Aug. 3-5 and 10-12. Thursday, Friday and Saturday performances are at 8.30 p. m. There is a charge. Call 549-8592.

Falls Church offers its Concerts in the Parks series at Cherry Hill Park behind the City Hall building at 300 Park Ave. Blankets or chairs are suggested. In case of rain, concerts will be at Falls Church Community Center, 223 Little Falls St. All programs will begin at 7 p. m. except on Sunday, July 23, when the Kaleidoscope Jazz Ensemble will perform at 2 p.m.

The 7 p.m. concert series includes July 7, U. S. Navy Country Current (bluegrass); July 21, U.S. Navy Port Authority (rock); July 27, Foxes Concert Band; Aug. 3. Foxes Jazz Ensemble; Aug. 31 and Sept. 28, Falls Church Civic Band. For more information, call 241-5077, Weekdays.