Sexy coast-to-coast styles

(InStyle.com) -- The dress codes, cool shops and hot spots unique to six cities -- with Katharine McPhee modeling each city's style.

It may be called the United States, but some cities in it have their own distinct dress codes -- especially at night when the partying begins. In our first ever cross-country fashion report, we asked stylish insiders in six cities to define their locale's unique look.

And we tapped American Idol sweetheart Katharine McPhee to be our true-to-life model: This L.A. girl may be from the town that invented casual chic, but she loves to dress up in whatever time zone her "Love Story" radio tour takes her.

New York: Slinky but serious

If you want to make it here, your clothes have to work as hard as you do -- even on a night out. So it makes sense that club-goers sizzle in silver or turn to black and charcoal, with hues like emerald and amethyst adding pop to the uptown/downtown look. "Embrace the idea of dressing like a lady," says Roopal Patel, fashion director of Bergdorf Goodman. "There's a level of polish from head to toe, from the drop earrings and the drop-dead dress to the dark stockings and the perfect heel." Peek at McPhee in six city styles »

Chicago: Savvy shoppers

It's not just the Windy City; it's the Indie City. Here, women are comfortable in their own skin and dress to please themselves, filtering fashion with an eye for what's unique, personal or vintage. "When trends come out," says Tricia Tunstall, co-owner of P.45 in the Wicker Park neighborhood, "we pick the ones that work for us." A clear winner: high-waist trousers for chilly nights that dress up well with patent-leather belts, statement jewelry and envelope clutches -- "beautiful and smart," Tunstall says.

Dallas: Shining stars

"Dallas girls like to shine," says Neiman Marcus fashion director Ken Downing. And while the mercury may be holding in the high 80s come fall, the fashionable never take shortcuts. Always put-together, style setters mix sophistication and glamour in subtle ways. Labels are as important as the right invites, and evening wear is a bold but feminine take on sexy. One perfect ensemble: a satin dress (who's afraid of statement red?), impact jewelry (all the better if it's heirloom) and a touch of patent leather.

Miami: Short but not sweet

In a city that considers bling a staple, the jewelry is real and the hemlines are high. Deeply influenced by Latin American residents and jet-setters, "Miami likes the mini, whether it's trendy or not," says Atrium's Christine Lee. For this season's party circuit, South Beach beauties balance wee skirts with a breezy blouse, a halter or a one-shoulder top. In itsy-bitsy dresses, a bustier, Empire-waist or playful bubble style reigns. Winning final touch: Status shoes trump It bags.

Atlanta: Sophistication rules

In a city of fancy mansions and hip-hop moguls, you'll find born-and-bred polish, plus a big-city edge. As Teresa Hebert, owner of T boutique, puts it, "Atlanta style combines the best of both worlds. We are fashion forward without losing our innate feminine charm." A graphic shift and sexy, sweet ankle-strap heels strike a chord here, as do trouser jeans with a cropped sequined jacket. As for accessories, this peach is also a material girl: Patent, cashmere and metallics are her go-tos this fall.

Los Angeles: Hollywood nights

It's hard to find a place in L.A. where a great pair of jeans won't take you, given the city's enduring crush on casual glam. Style here is all in the well-chosen details: a peep-toe pump, a status clutch or a serpent cuff. Angelina Jolie, says Fred Segal's Joey Tierney, embodies the laid-back luxe look. In the fall lineup -- Little dresses, pencil skirts and a moody palette of gray and purple that alternates with vivid new blues and black. Nights can turn chilly, so Angelenos keep wrap sweaters on hand in the Prius. E-mail to a friend

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