It started with Instagram. Or maybe it ended with Instagram. Last fall, Christina Turner, a fashion stylist in Brooklyn, was dreading another New York winter in her cramped, lightless Greenpoint, Brooklyn, apartment while gazing longingly at the succulent gardens and festive backyard dinner parties posted on social media by her friends in Los Angeles.

“I’d see all these old familiar faces of friends I once knew in New York, all seated at the same table,” said Ms. Turner, 32, who goes by the professional name Turner.

She could resent them, or she could join them. So in November, Ms. Turner dumped her furniture on Craigslist, piled into her battered Honda Accord and headed west, not stopping until she found a light-filled two-bedroom cottage in Echo Park, a neighborhood in eastern Los Angeles that is a magnet for young creatives.

The wagon train mentality, it seems, is taking hold among the L train set: Go west!

In an era when it has become fashionable for New Yorkers to grumble that their own city is becoming a sterile playland for the global-money set (Dubai with blizzards, basically), Los Angeles is enjoying a renaissance with a burgeoning art, fashion and food scene that has become irresistible to the culturally attuned.