The Carter Barron Amphitheatre, the metropolitan area's only in-town outdoor concert venue, announced its summer schedule yesterday. The 4,200-seat facility at 16th and Colorado, now in its 36th year of operation, will host a season heavy on popular soul and R&B acts such as StarPoint and Sly Fox (July 12), Stephanie Mills (June 28) and the O'Jays (Aug. 2, 3), with a smattering of jazz, blues and gospel.

Among the highlights:

Washington debuts for Milton Nascimento, Brazil's most renowned musician (June 22), and the Miami Sound Machine, whose hot Latin pop styles are currently surging up the charts (August 10).

The Washington farewell for longtime local favorites the Nighthawks, with such guests as Pinetop Perkins, John Hammond and Guitar Jr. (July 5).

Jazz legend Miles Davis with Special EFX (Aug. 9).

The 1986 season kicks off June 7 and 8 with new resident Jennifer Holiday. The opening night will be a benefit for the Carter Barron, with tickets priced at $12.50. The following night, ticket prices will drop back down to the summer price of $6.50, one of the best bargains in town. Unlike Wolf Trap, which is run but not booked by the Park Service, the Carter Barron operates on Park Service funds.

The season continues with Phoebe Snow (June 14), Kid Creole and the Coconuts (June 15), Nancy Wilson and the Widespread Jazz Orchestra (June 21) and a hip-hop show with Lisa Lisa & Cult Jam, Roxanne Shantee and the Brazilian fusion jazz band Azymuth (June 29).

July shows include Colonel Abrams (July 6), Cherelle, Alexander O'Neil and Cashflow (July 13), Rene and Angela (July 19) and the Manhattans and Pieces of a Dream (July 26). August dates include Mtume and Roy Ayers (Aug. 16), Angela Bofill and Rose Brothers (Aug. 17) and George Howard and Cissy Houston (Aug. 23). The season will close with a gospel festival headlined by the Winans (Aug. 24).

The National Park Service also runs a series of free jazz concerts at Fort Dupont Park. The schedule there:

Noel Pointer and Dave Valentin (June 20, 21); Ahmad Jamal (June 27, 28); Herbie Mann (July 11, 12); the Dirty Dozen Brass Band (July 18, 19); Horace Silver Quintet (July 25, 26); Motown Revue with Jr. Walker and the Allstars and the Marvelletes (Aug. 1, 2); Airto and Flora Purim (Aug. 8, 9); a blues festival with Jimmy Witherspoon and Johnny Copeland (Aug. 15, 16); Bobby Hutcherson and Al Foster (Aug. 22, 23).