West Side Story is the musical that the Fox Theatre has been waiting for. It is one of Broadway's and everybody else's treasured modern classics, and even in a so-so production it fills up the vast steppes of the Fox in a way that no downsized Evita or South Pacific has done.

The 1957 West Side Story which is Romeo and Juliet with dancing and gang war, is not as cool as it was 33 years ago with all the finger-snapping, teenage swagger and '50s jazz riffs. Opening night at the Fox was not cool at all; the 5,000- seat auditorium was stifling as playgoers wondered where the air-conditioning went.

Thermodynamics aside, the touring one-week stand of West Side Story is still the amazing aural experience that Leonard Bernstein created out of that era's durable jazz and Latin rhythms, along with operatic vocal stretches in the ballads and a little boost from Aaron Copland. The combination is so exotic in American musical theater that, still, it seizes the imagination and the ear.

Yes, one day these touring shows will figure out how technically to broadcast clearly with their body microphones and their rock-and-roll speakers. But what is a playgoer to do with a show that comes and goes in six days?

Betsy True, for example, as the star-crossed Puerto Rican Juliet, Maria, well may be a stupendous soprano. But when her body microphone is malfunctioning, she cannot be understood, let alone treasured.

The orchestra, however, conducted by Joseph Klein, did excellent service to the Bernstein score, with all those dissonant horns ramming against the strings, the castanets and the clamorous arrangements that sound like a Copland soundtrack for a runaway subway train movie.

That is what fills up the Fox: the ocean's roar of unique theater music, by a composer with a lust for excitement in his work. Bernstein, with his young lyricist Stephen Sondheim, wrote ambitious, energized songs that mainly are dance numbers.

At the Fox, those dances help fill up one of the largest stages in America. Dancers work very hard in this show. Alan Johnson's recreation of Robbins' original staging has Spanish Harlem kids hurtling out in diagonals from both rear corners of the stage, in straight lines that slice in between their opponents' paths. It is a kind of choreographed warfare, a battle for territory in dance.

Like Romeo, Tony (Peter Gantenbein) sees Maria's Juliet at a dance and is smitten instantly. The Puerto Rican girl and the New York boy (whose real name, incidentally, is Anton; he's Polish) end in tragedy after a rumble in which he accidentally kills her brother. Now there is some lethal edge missing to this production. The Anglo gang, the Jets, through a combination of casting and costuming, are a fairly neat, corny-looking band of youths. One even wears a straw hat and horn-rims, like somebody in one of the malt shop fistfights in an Elvis Presley movie. The Puerto Rican Sharks are much more convincing, but then they usually are, notably the impressive Robert Montano as Maria's brother, Bernardo.

What it all comes down to -- as the Fox promises its air- conditioning will be super-duper by tonight -- is the famous music: Tony's poignant love song "Maria," Maria's "Tonight," their love duet "One Hand, One Heart" and the amazing modern ballet for "Somewhere." The jazzy number "America" also knocks you out. It is ripped through by Jackie Lowe, as Maria's peppery friend Anita, and it has those Sondheim lyrics that rhyme "Everyone knows in America, Puerto Rico's in America," and the musical theater does not get much better than this.