FARGO, N.D. — Sunnyvale Forecast, a free weather app downloaded 11 million times and opened roughly once a day by people standing in doorways, was promoted to chief meteorologist at KLMN-TV on Tuesday after correctly predicting a 40 percent chance of doing whatever it wants.

The announcement came during a brief ceremony in which the app was handed an employee badge, which was placed on the phone and immediately slid off.

“Over four years, Sunnyvale has never once been wrong,” said station general manager Dale Pruitt-Okonkwo. “It said 30 percent chance of rain, and it rained, or it didn’t. It said partly cloudy, and there were clouds, in part. Frankly, our previous meteorologist kept saying things like ‘rain at 4 p.m.’ and then being held to them.”

The app’s methodology, detailed in a 600-page document nobody has opened, has been described by experts as “a coin that has never once been flipped.”

“Traditional forecasting commits to an outcome, which exposes the forecaster to reality,” said Dr. Marguerite Volkenstein-Pratt, senior fellow in Probabilistic Hedging at the Institute for Atmospheric Plausible Deniability. “Sunnyvale has pioneered a model in which every possible future is technically included. It’s elegant. It’s also a little like predicting a baby’s gender by saying ‘one of the two.’”

Viewers were largely supportive. “I trust it because it never lets me down, and it never lets me up either,” said Fargo resident Tom Hallbeck, 54, who carried an umbrella to his own wedding, in July, in a drought.

The app’s first broadcast as chief meteorologist ran nine minutes, during which it displayed a sun, a cloud, a raindrop, and a snowflake in a rotating carousel, along with the phrase “Conditions may vary.” Ratings rose 14 percent.

“It said 40 percent chance of whatever it wants, and then it did exactly that. That’s called accuracy.”

The quote was attributed to Pruitt-Okonkwo, who added that the app has already requested a corner office, a reserved parking space, and a “50 percent chance” of a raise.

Not everyone is celebrating. Former chief meteorologist Gary Lindqvist, 61, who had correctly forecast a blizzard in January, said he was “surprised but not shocked” to be replaced by something that has never been held accountable for a blizzard.

“I said eleven inches and we got eleven inches,” Lindqvist said. “They told me that was ‘a little specific.’”

The app’s push notifications have also been upgraded for the new role. Residents now receive alerts reading “Weather is happening” at unpredictable intervals, along with a daily reminder to “check back later,” which analysts say has driven a 300 percent increase in people checking back later.

At press time, Sunnyvale Forecast had issued a severe thunderstorm watch for “possibly today, possibly not,” and the station had scheduled a follow-up segment to clarify that it could not be reached for comment, but might be.