UNTIL recently, Judith Jamison was one of the divas of dance -- a leading light of the Alvin Ailey American Dance Theater, star of the Broadway production of "Sophisticated Ladies" and guest artist with many a ballet company here and abroad.

Then in 1984, after 15 years on the professional stage, she began a new career as a choreographer, making a piece for Ailey's troupe, another for Maurice Be'jart's Ballet of the 20th Century in Brussels, and a third for the Dallas-based Dancers Unlimited.

This weekend, The Washington Ballet presents her latest opus, "Time Out," a light-hearted work whose title signals a break from the classics, a downhome romp.

Divided into four sections, "Time Out" starts out upbeat, shifts to a jazzier, more romantic mood, slows considerably and ends robustly. The commissioned score by guitarist Ken Hatfield is rooted in a variety of American sources, among them the music of the Blue Ridge and Appalachian mountains, and the wide-open harmonies of Aaron Copland. The eight dancers wear folksy garb, and the women do not dance on point.

Jamison's piece should provide a fine contrast to the other works on the program: resident choreographer Choo San Goh's haunting "Synonyms," to music of Benjamin Britten; and George Balanchine's "Allegro Brilliante," one of the master's rapid-fire, crystal-clear movement essays.

THE WASHINGTON BALLET -- Friday at 8, Saturday at 2 and 8, Lisner Auditorium, 21st and H streets NW. Tickets: $17.50, $15. Call 432-0200.