The 10th annual Indy Jazz Fest seemed to be wearing its anniversary best and struttin' its stuff during most of its third and final day Sunday in Military Park.

But while Paquito D'Rivera was wrapping up a fascinating duo set as the middle act in the AARP "Legends of Jazz" tour, the skies darkened. Delighted as it appeared to be by D'Rivera's clarinet and alto saxophone -- and the alert, energetic piano of 20-year-old Alex Brown -- the crowd began to pack up and head for the exits.

When D'Rivera's hour was up, festival artistic director Joel Harrison came onstage to announce cancellation of the finale unless the storm passed over.

No such luck. Fourplay, a contemporary jazz quartet with some weather-related travel issues of its own earlier in the day that had put its appearance in question, was waiting backstage to go on when bad weather brought the curtain down.

The afternoon had begun brightly with a poignant appearance by the IUPUI Jazz Ensemble, until a little over a month ago trained and directed by drummer Jack Gilfoy.

Shortly after Gilfoy's unexpected death in early May, Avon High School band director Bob Burns, who'd played in the 18-piece band alongside the students, took charge.

The group gave a good account of itself presenting several numbers associated with Count Basie -- an impersonation made especially vivid by the astute piano playing of Manny de la Rosa.

Other than Basie material, the band took advantage of Gilfoy's friendship with Oliver Nelson Jr. to feature him as guest soloist. The ebullient flutist brought along a few pieces by his short-lived, widely admired father, including the peppy "Flute Salad" and the demanding "Reuben's Rondo."

Because of the illness of Aaron Parks, the APA missed the achievement of having a Cole Porter Fellow (winner of its triennial jazz piano competition) scheduled on each of the festival's three days. Parks' place on the schedule was capably filled by the rest of his quartet: guitarist Mike Moreno, bassist Thomas Morgan and drummer Eric Harland.

Moreno is a fluent improviser with a purring melodic line and an inventive knack for harmonic support -- thus ideal to fill in any gaps left by the absent pianist. Morgan's lyrical approach softened the abstract contours of some of the trio's music, though there was nothing remote about the emotion in a Parks ballad, "Memory of a Flame," which drew tender playing from all three.

Sunday's vocalist was Robin McKelle, whose set drew respectfully on her admiration for black singers while reaching deep into an individualized sultry energy. Touches of Dinah Washington, Nancy Wilson and Ella Fitzgerald were evident in her interpretations without the effect of parody. She had deft, idiomatic support from her regular accompanists: Alain Mallet, piano; Peter Slavov, bass, and Jeremy Clemons, drums.

Before D'Rivera's amazing display of passionately applied technique on both clarinet and alto, the Ramsey Lewis Trio offered a set of some its patented pop jazz, beautifully inflected from "Wade in the Water" on, and leaning heavily on the pianist's musical origins in the black church and some that tradition's most indelible melodies.