Another bowling center in another shopping plaza in a suburb of another American city. Practice from 9 a.m. to noon, the pro-am starting at 1 o'clock. If that's the schedule, it must be Tuesday on the Professional Bowlers Association tour.

Outside, the sky is the color of a battleship. The weather, and therefore the mood of the world at large, is melancholy. But the roof doesn't leak, so nobody seems to notice.

On the PBA tour, there was no such things as sunshine or rain. There is no springtime, only the winter tour and the summer tour.

This week it is the Fair Lanes in Springfield Plaza, just of I-95, a few miles south of Washington. This is the 14th stop on the winter tour. It is not much different from the 13th (Kendall, Fla., outside Miami) or the 15th (Imperial Lanes, Toledo Ohio).

Through the glass door are a highway, a drugstore, a supermarket, the local franchises of chains specializing in rubber chicken and greasy burgers - all the plastic palaces of Suburbia, USA.

Most of the out-of-toun bowlers are staying at Holiday Inns and Howard Johnson's Motor Lodges. They drive rental cars - doubling or tripling up, as they do with motel rooms, in order to save money - and are primarily interested in the most direct route to this week's "house."

"During the week, it's all motel-restaurant-bowling center," says Dick Ritger, 38, president of the PBA, winner of 17 tournaments since he joined the tour in 1965, six years after it was founded by an Akron attorney named Eddie Elias.

Back home in River Falls, Wis., Ritger has a wife and four children, but on the road he has roomed for 13 years with Wayne Zahn. Only a handful of the bowlers take their wives with them on tour.

"I know them (the wives) by sight, but I honestly don't know most of their names," says Ritger, whose memory is much better when it comes to the characteristics of the bowling establishments that host tour events, the depressions and tracks and ridges in every lane, the hundreds of thousands of balls he had rolled and precisely how each one of them reacted.

Considering that some 90 to 100 bowlers travel regularly and make most of the 35-odd tour stops each year, the have little sense of community. There are exceptionally close-knit cliques - "Dave Soutar and Johnny Petraglia and Dave Davis always hang together, they are as close as brothers," says Ritger - but surprisingly little group identity.

Ritger had just finished practicing for the start of today's (9 a.m. competition and had changed from his bowling shirt into a leisure suit in the "Players' Paddock," a small room cramped with racks of bowling shirts, boxes upon boxes of 16-pound balls and bags filled with each man's individual paraphernalia: shoes, gloves, resin bags, lucky towels, all the tool sof ade that is more complicated than it seems.

The average pro travels with two or three pairs of shoes and anywhere from four to 10 balls. They are all different - some rubber, some plastic, with various degress of hardness - and are plugged with a mind-boggling assortment of weights to suit particular lane conditions.

"Every lane is different, depending on the surface, the finish, the oil or dressing on top of that," says Ritger. "Conditions vary with wear and the time of day. The pro has to read them like a map. The characteristics may not be visible to the eye, but as soon as he rolls the ball and sees what it does, he can tell.

"It's a very precise, exacting art. That's primarily what differentiates the pro from the good amateur - the ability to read the conditions and adjust to them.

"Of course," he adds, "there are other factors. As in any sport, desire and determination separate the players who have the basic ability. Some people in life want to win more than others.

"Experience is important - if you've lived through the pressure before, you have an advantage. And there's the matter of getting the breaks. Two guys might hit the pocket solid 10 times in a row. You carry the strike on the last one, the other buy leaves a 10-pin. The difference at this level is very minute."

As Ritger spoke, all 40 lanes were filled with bowlers getting in their last minutes of private preparation, moving from lane to lane, getting a few extra rolls on the ones that had been troubling them cost.

A man named Henry Vogt rolled four consecutive strikes but remained totally impassive, not a hint of a smile on his lips.From the neck up, he looked like a Marine drill sergeant - austere, with an old-fashioned flat top. There are many 1950s hair styles on the tour; the splendidly-tattooed man next to Vogt was coiffed precisely like the Fonz.

From the neck down, Vogt is not what you would call a portrait of fitness. Thirty-four years old in February, he stands 6 feet tall and weighs 280.

He probably will not be among the one-third of the 144-man field that will go to the pay window. The man who comes out on top in Saturday's nationally televised finals will earn $14,000. The lowest money-winners will collect around $300.

Vogtt is from Baltimore, one of the 28 "regional pros" competing here. They belong to the 1,500-member PBA but enter only tournaments in their areas. Seventy-five of this week's Bowlers are "touring-1s" who entered 22 tournaments or more last year; 25 are classified "Touring 2s" who were in between 15 and 21 tournaments, and 16 are local qualifiers.