It’s a “scary, exciting time” at the Weather Underground, says co-founder Jeff Masters. In July, the seventeen-year-old U-M spinoff announced its sale to the Weather Channel, a longtime suitor.

“It’s a bit of a culture shock, but it’s also a really good move,” Masters says. The company will keep its local seven-person office in Kerrytown; its bigger San Francisco office will become a Weather Channel regional headquarters.

No sale price was released, but Masters says the WU tripled its staff in the last three years, to fifty-seven employees. That forced the four co-owners to spend more of their time on management, and less “doing their thing.” Handing off administration will give Masters more time to devote to his blog, an incisive analysis of how current weather events, like the recent heat wave, tie into global climate change.

The merger means the Weather Channel now owns both of the Internet’s most-visited weather sites. Ranked by daily visitors, Masters says, the Weather Channel’s weather.com usually ranks about thirtieth globally, wunderground.com around seventieth–higher during hurricane season and other natural disasters. While wunderground.com will remain independent after the merger, some of its most popular features will migrate to weather.com–making official a longtime pattern of the larger company adopting WU’s innovations. “Imitation is the sincerest form of flattery,” says Masters. “And in that sense they were constantly flattering us.”

Some staffers were in shock after the announcement. Shaun Tanner–an eight-year employee whose skills, like those of many others at WU, combine meteorology and computer programming–blogged that “it felt as if something was being taken from me.” The company’s culture valued thinking outside the box: “No idea was too crazy for the Weather Underground,” Tanner writes. But he adds that many good ideas fell by the wayside for lack of resources to implement them; now, that will change.

Masters says weather.com gets about three times as many visitors as WU, and he’s already thinking about ways to leverage that bigger audience. Since many weather.com users submit local weather news via Twitter, he’s looking at what it would take to post that information automatically to online maps.