I’m watching a trend develop in beer: the chelada. It’s still well before the crest, but all the signs are there: Big brewers are investing solid money (Miller and Anheuser-Busch are already in), sales are ahead of forecasts, and marketers are getting their backstories in order. It’s going to be a big one.

What’s a chelada? Also known as a michelada (pronounced meetch-a-LA-da), it’s a Mexican beer cocktail. In its simplest form, it’s just a light lager in a salt-rimmed glass with a squeeze of lime and maybe a handful of ice cubes. It’s a thirst-quenching beach drink: Corona meets margarita.

The fun starts when you get into the spirit of the name, which in Mexican slang means “my little cold one.” It’s yours to customize, in other words, and people do, mixing in Worcestershire sauce, Maggi seasoning, Clamato, chiles, soy sauce—whatever makes it right. Now it’s a brunch drink: a beery Bloody Mary.

This has been happening in bars and on front porches for years and not just in Mexico. A Corona is rarely seen without its lime wedge, and it’s just a short tequila two-step to a salted rim. Tomato juice mixed with beer is popular in the Midwest, where it’s known as “red beer” or “red-eye.” Canadians go wild for Clamato and beer—a “two and juice,” says a friend of mine in Ontario.

Take that kind of at-home innovation and interest and dangle it in front of a beer industry that’s seen wine, spirits, and craft beer booming on variety and differentiation, and someone’s going to snap it up. Miller Brewing got into test markets in March with Miller Chill, a light beer with a dose of salt and lime flavoring.

Carl Cahill, the brand manager for Chill, explains that the company was looking to capitalize on consumer interest in different flavors in beer. “Our initial direction was a lemon-flavored shandy,” he says, “but the chelada-inspired lime-and-salt combination showed greater potential to deliver mainstream volume at worth-more pricing.”

“Worth more” is a holy grail at Miller. It’s the part of the beer market they see Corona, Heineken, and craft beers tapping into, with beers that consumers are willing to pay a substantial premium for. Salt, lime, and a lightly played aura of Mexican heritage on the labeling and advertising make Chill worth more, the company hopes. Customers apparently agree: After successful tests in incrementally larger areas, Miller took Chill national in June.

Anheuser-Busch took the bolder red-beer route with two products that are mixed with Clamato: Budweiser and Clamato Chelada, and Bud Light and Clamato Chelada. The brand names are prominent for a reason. A-B and Mott’s, the maker of Clamato, have been cross-marketing the drinks with “red beer” and michelada promotions for more than five years, according to innovations manager Kathy Sattler, who’s part of an institutionalized innovation department at the giant brewer. “Consumers had voiced their opinion that they liked beer mixed with Clamato,” she says. “The idea was prepackaging, having it ready to go.”

The Clamato and spice give the drink some real guts. It has a garden freshness, some Southwestern flavor, a little heat, and a clean finish that left me looking for a plate of steamed shrimp and fresh tomatoes. The labeling encourages you to spike the beer with whatever additions you like: michelada, indeed.

Anheuser-Busch began test-marketing its cheladas in areas of Texas and California in March, expanding to the whole of both states in June, “due to unprecedented demand,” according to Sattler. They’ve since expanded to Arizona, New Mexico, and the Chicago area, and plan to go nationwide on January 1.

But what happens after the crest? Will this be a solid niche for the big brewers, a year-round player for years to come? Or will it blossom and quickly fade like so many other promising fast sellers: dry beer, ice beer, low-carb beer, and the flavored malternatives?

Beer runs in cycles. A new idea comes along, and for a while—helped along by promotional spending—it’s all anyone can talk about. If it does well, everyone else tries to cash in with their own version. But shortly after everyone jumps in, the demand for the new product often falls. Too many beers of the same type make it painfully obvious if there’s not that much substance behind the hype.

“My little cold one” is pretty hot right now and getting hotter than a chile piquin. But brewery innovators will want to have the next new idea slotted right behind it if—or, rather, when—it cools.