It was about 15 minutes before the start of the Cleveland Orchestra's Monday evening concert at the Kennedy Center. Most of the players were sitting on stage in their tailcoats, tuning away as if everything were normal. But there was one thing missing: the orchestral parts for the opening composition, Beethoven's "Egmont Overture."

Some of the players were absent as a result of the storm, and conductor Lorin Maazel had to scratch the entire scheduled program (the Sibelius 4th and Mahler 6th symphonies) just hours beforehand and substitute works that could be performed with the players who were present. Three oboe players had been snowbound in Bethesda, where they had stayed overnight with friends. Furthermore, the extra brass and wind players necessary for the Mahler could not be flown in from Cleveland.

So the orchestra and Maazel faced having to perform a demanding program, no opportunity to rehearse it and their scores to the opening composition in Cleveland.

Finally, a key to the National Symphony's library was located, and the NSO's parts for the Egmont were distributed around the stage.

Meanwhile, the audience trudged in slowly, after braving the ruts and drifts of unplowed New Hampshire Ave. Patrons were told to sit anywhere they chose and the normal rule against entering except during breaks was wisely thrown to the winter winds. Gradually the audience grew to at least three to four hundred.

Impresario Patrick Hayes said that what he had in mind was "a sort of informal public rehearsal." But from the moment that Maazel brought down his baton on those two slashing octaves that begin Egmont, it was clear that this was to be no mere well-intentioned run-through. There aren't a dozen orchestras anywhere that could have attacked that work's opening with such precision and force even if they practiced them all day.

As the overture proceeded, the strings hit those ensuing hard accents and tricky fugal figures with equal virtuosity. It's amazing how the Cleveland players clear up one acoustical problem that has been bothersome in the Concert Hall, a weakness in projection by the strings seated at the front of the stage. It's a combination of rich body with a bit of an edge.

The succeeding performance of Mozart's sublime 40th Symphony was exceptional in a different way. Maazel was responding to the work's understated tragedy with subtle differences in dynamics and note values. Technically, the 40th is not hard to play; interpretively it is treacherous. After 25 years of playing it under George Szell and then later under others, probably no other ensemble is more attuned to its intricacies; it showed Monday night.

The concert then ended with the Brahms 4th Symphony, in an interpretation that had considerably more natural shape and greater momentum than the one Maazel conducted at last season's Kennedy Center Brahms festival.

There may have been a few moments when Maazel would have preferred a slighly more exact balance or tighter ensemble. But apparently an unrehearsed Cleveland sometimes plays even more musically than an overrehearsed one.

By evening's end everyone in the hall seemed to realize that nature's imposed hardship had produced a very special event. The audience produced a tremendous ovation. And, realizing the effort of the listeners to come hear them, the Clevelanders and Maazel returned the compliment with applause for the audience -- an almost unheard-of gesture from an American orchestra.