Beaches, palm trees, balmy temperatures - Southern California has it all and is a perfect place to chase the winter blues away.

It's also a perfect place to show clothing for warm weather. Those bright colors, lightweight fabrics, fun and fanciful prints and snappy sportswear styles look right at home in L.A. No wonder the Men's Fashion Association selected the city for its recent spring and summer press preview. And what a show it was! Four days filled with designer presentations - such names as Ronaldus Shamask, Allyn St. George, Andrew Fezza, Bill Robinson, Tony Lambert, Richard Mishaan for Chose Classique, Dimitri Couture, Cecilia Metheny and Henry Grethel. Four days filled with informative seminars, panel discussions, gala awards ceremonies and glittering parties galore.In attendance were fashion editors and broadcasters from all across the nation. And in between enjoying the sunny weather (how does 70 degrees sound?) they heard an even sunnier forecast for the days ahead.

Spring menswear, said Chip Tolbert, MFA fashion director, will offer the style-cosncious male more attractive options, more variety than ever before.

More eras than ever before will be influencing business and contemporary dress, too. The modern generation is reaching into the past to find ways to express itself, he said. And "expressive dressing" is coming in the form of '30s-inspired suit silhouettes, '40s-inspired accessories and '60s-inspired sportswear.

You could safely say there's a touch of deja vu in menswear these days. But just a touch. Designers have taken the fashions that were so popular yesterday and updated and reworked them so that they're in vogue and viable for the fast-paced, demanding lives lives men lead today.

Of course, not everything's retro. Many styles being featured in designer collections for spring are strictly now, extremely progressive. Take the shorts that are being shown, for instance. And we don't mean the casual shorts cut out for the Southern California beach. The shorts we're referring to are sophisticated and citified versions clearly meant to be seen at the club or on the street.

A season or so back, these citified shorts first appeared on the scene teamed with smart sport jackets. Today they're more popular than ever and there are even new variations on the theme.

"We've removed the coat, added a classy vest," explained Tolbert. "We call it `sports coatless dressing.' "

Whether a man opts to put a jacket with his shorts or one of the handsome new vests (there are literally dozens of styles in every fabric and color and print you can imagine), both ideas provide viable alternatives to traditional male attire. And members of an ever-growing community of creative West Coast designers are daily dreaming up a whole raft of other options as they break barriers and revolutionize ways of making clothing.

Who says pants can't be cut in a different way? Who says jackets have to button in the familiar manner? Who says you can't use unconventional fabrics? Who says off-beat color combinations aren't OK? These are the kinds of questions Californians such as George Machado for Zylos, Emil Rutenberg, Glenn Williams, James Cavaricci and Karl Logan are asking as they turn out their highly original collections.

"We have a great deal of creativity going on here in L.A. It's exciting," said Ron Arden, who directs menswear at the California Mart, and loves Los Angeles not only for its sunny climate, but for the way it inspires and nurtures innovation. Yet, he hastens to add, it isn't just in California that things are happening. From coast to coast, the menswear industry's much more interesting than it used to be and promises to become increasingly distinctive and diverse as the years go on.

Distinctive and diverse. They're the key words to menswear's future - a bright and promising one. They're also the words that can best be used to describe suits for spring and summer.

Do you like double-breasted styles? You're in luck. That's what many designers are promoting. Prefer single-breasted versions? Well, they're around, too. Both peak and notch lapels are available, and closures run the gamut - six-button, four-button and two.

Softer construction seems to be influencing every suit in the market, as does a more generous cut that manufacturers have been adopting to accommodate the American male who's heavily into exercising, body-building and physical fitness. Shoulder-to-shoulder measurements in most suits have grown - from 18 and 19 inches to 20 and 21. An 8-inch drop from the chest or first button to the waist (it used to be 61/2) now is common (this fits larger upper-body dimensions.) Jacket waists are slimmer; forearms are wider.

Three-button suits, with lapels rolling to the second button, also are coming on strong - a silhouette that reflects a return to the '30s and the elegant look of Cary Grant, Ronald Coleman, Walter Pidgeon and Adolphe Menjou. Indeed, there's an easy elegance everywhere, according to the MFA. Rather than the inverted V, a more comfortable wedge shape is becoming prevalent with no vents on the jacket. Pants are cut fuller with pleats. Sizing is slowly starting to swing over to the much simpler sportswear terms: small, medium and large.

Natural fibers are preferred by most leading menswear designers, although blends such as wool and polyester are definitely part of the story. And color - well, that subject deserves a whole chapter all to itself.

Traditional favorites, navy and gray, are still being touted by the industry and bought in large numbers by retailers who will soon have them on their racks for spring. But purple's what designers really want you to wear to the office and everywhere else during the season ahead. It's the hot - sizzling hot - new menswear shade.

Most people believe menswear designers developed a passion for purple after seeing how it brightened women's wear runways in recent seasons. Anyway, the color once relegated to royalty now reigns supreme and you'll be seeing it in every tone and variation from the deepest hue to the softest and most subtle shadings.

When intense purple is used alone, it's a shocker and requires a very confident man to carry it off. But when it's used in a more understated way, to add spice to glen plaids or pinstripes, purple can work for even the most conservative male.

The season's most popular color also works well as an accessorizing touch - in paisley ties; as an ascot or pocket square; in a sweater or shirt pattern.

For those who still aren't convinced - rest easy. There are many other colors to choose from this spring - refreshing colors that can light up your wardrobe just the way flowers light up Southern California hillsides even in the dead of winter.

In addition to lilac, violet and rose, a variety of soft pastels can be found - especially in the shirt department. And keep in mind that with shirts, details make the difference. Watch for fly fronts, spread and tab collars, French cuffs. These are the design touches that count and that will instantly update your closet.

Also designed to update a man's closet for spring are slacks that are wider at the knee and narrower at the ankle - a style that seems to look best in subtle glen plaids, retro stripes and checkerboard patterns.

With these slacks, and with good-looking denims, designers are showing all kinds of handsome sweaters. Sweaters, in fact, never have looked better in cotton, linen and/or ramie blends. Perhaps the most important knit of the season is the cardigan. It's frequently being offered as a casual and classy substitute for the sport jacket. And, emphasized Tom Julian, associate fashion director of the MFA, don't let the idea make you nervous. There isn't a thing wrong with wearing a cardigan in place of a suit coat once in a while. Doing so can be the very essence of "expressive dressing" and can set a man apart as someone who handles his clothes with a sense of fun, flair and real individuality.

If that idea intrigues you - if you'd like to handle clothes with individuality and flair - learn how to use the vest, one of spring's most essential menswear pieces. It can provide dozens of bright accessorizing touches to otherwise bland outfits. And that brings us to the power of accessories.

For years, women have understood accessory magic. Now, at last, men seem to be recognizing its importance and are taking the time to seek out and invest in the right finishing touches - belts, suspenders, socks, shoes, sunglasses, ties.

Doing so, they will find, will pay economical as well as fashionable dividends.

Clothes are costly these days, increasing in price all the time. One of the best ways to cope lies in purchasing just a few good things, then giving them a variety of different looks with wisely-chosen accessories.

Some of the finishing touches that are wise purchases this spring have what the MFA calls "crossover tendencies." It means they work two ways. Belts enhanced with perforations, kilties, webbing and hardware work for both business and sport. Loafers can go to the office and also can be be teamed with cords and jeans on weekends.

Another hardworking accessory is the tie. It can perk up just about any old suit or sport jacket in your wardrobe and look stylish for years to come. When shopping for ties this season, remember that bolder is better. Wide ties in dramatic art deco designs are the latest rage. (Some of the best are being designed by a new name on the scene, Terry Dobris, who creates cravats for Format.)

Other designs that comprise spring's best offerings: tie-dye togs that smack of the wild '60s; anything festooned with smiley faces (the motif's a sportswear favorite); clothes with nautical overtones; white and black jeans; saddle shoes and keds