Modish couples ring the tables. The bar is jammed with students, young professionals, and self-styled bohemians. Conversation gradually succumbs to the syncopated rhythm. "It's a merengue!" someone cries as a new tune begins, and the little dance floor suddenly is jammed. It's salsa night at Cafe de Artistas. Latin music and dancing are thriving in at least half a dozen nightspots sprinkled across town. The music of Latin America and the Caribbean has steadily found its way into each generation of North American popular music. Current examples are the penetration of reggae into rock'n'roll and the blending of salsa with disco. The growth of the Latin population and the increased sophistication of Washington natives now permits discos and clubs to draw a full house every weekend to hear cumbia, salsa, merengue, and samba as they are played south of the border.

MACHU PICHU plays Tuesdays and Sundays at 328 CAFE DE ARTISTAS on M Street in Georgetown. Led by saxophone player STEVE FELDMAN, the quintet has become a permanent fixture in Washington, sharing the spotlight with imported Caribbean bands at special engagements.

FERNANDO VILLALTA and LATIN SCORPIO play Friday and Saturday nights at LE RIGOLO above the restaurant DON QUIXOTE in Georgetown. The band's Caribbean sound, authentic and professional, has an irresistible appeal when combined with Villalta's singing. The new nightspot is centrally located near the corner of M and Wisconsin, but the capacity of Le Rigolo unfortunately quite small. Those dedicated souls who are still in the mood on Monday night may catch Scorpio at Cafe de Artistas.

Downstairs at CAFE DE IPANEMA, Washington's only Brazilian restaurant, the satiated patrons who stay past 9 can digest their feijoada while they dance to a lively little combo which plays both samba and salsa. Restaurant owners JOAO MIGUEL SOBRINHO and JOSE ALVAREZ preside over the nightclub as well, maintaining the warm and friendly atmosphere of a private party for their Latin and North American patrons.

A more appropriate name for THE CONNECTION might be "The Crush." The small bar and disco at 1106 20th Street is so packed with gyrating and imbibing Latinos that the absence of fights is just short of miraculous. TONY RIVERO, the weekend night manager of the Connection, attributed the bar's popularity to the enthusiasm of his Bolivian compatriots. A Colombian patron disagreed: "The major attraction is obviously the music. Listen to that cumbia!"

HAMMELS WEST is a resturant in Foundry Mall on Thomas Jefferson Street in Georgetown. Between 10:30 and 2 on Fridays and Saturdays, the restaurant turns Latin discotheque, swelling with enthusiastic dancers. The disc jockey obligingly plays national favorites on request, often ending the evening with a feverish round of Brazilian Carnaval music.

Despite its name and baroque decor, the THAI ROOM, on 13th below G Street, has achieved a popularity as a Latin disco. Serving Southeast Asian food during the day and early evening, the restaurant changes into a disco palace at 10:30 on Fridays and Saturdays. Marble and gilt columns lining the dance floor attest to the restaurant's previous Italian incarnation. Salsa, merengue and soul are skillfully mixed by ROLAND. A Latin music lover since his brother brought home a samba record more than twenty years ago, Roland pontificates: "The masses will have to go back to the rumba and the mambo in order for salsa to survive in the highest form. We must get back to the basic body movements and rhythms which can be easily mastered by the average North American."

The Dupont Circle area has several nighspots featuring Latin music. THE IMPERIAL HOUSE on K Street near 18th offers a soft melange of disco, rock, and salsa on weekends, while Thursday is Latin-music night at THE BERET on Connecticut Avenue.

The best way to keep current on the local live Latin sound is WPFW's program of Afro-Caribbean music.

CON DUENDE Y CACHE (With Grace and Style) may be heard at 89.3 FM between 4 and 6:30 Sundays. JOSE SUERO is the soft-spoken host who explains the evolution of Latin rhythms as he plays new hits and classic oldies. At some point in the program, which is conducted in Spanish and English, Suero reads a schedule of who is playing where in the coming week. Listening while driving can be dangerous.

Costs to dance at these Latin hotbeds of social rest vary from no cover charge at Hammel's West to a $4 admission at the Thai Room.